Franklin WHP a Jacket Design Spec

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See Page 29 for overall schematic of development

Jacket Design Specification

Doc No. WFA-S-SP-1000 Rev R2 Page 2

CONTENTS

Page

PURPOSE....................................................................................................................................... 1

SCOPE............................................................................................................................................ 1

1 INTRODUCTION...................................................................................................................... 7 1.1 BACKGROUND............................................................................................................................. 7 1.2 PURPOSE ..................................................................................................................................... 8 1.3 ABBREVIATIONS.......................................................................................................................... 9 1.4 DEFINITIONS................................................................................................................................ 9 1.5 REFERENCES .............................................................................................................................. 9

1.5.1 Design Information References...................................................................................... 9 1.5.2 Total General Specifications ........................................................................................ 10 1.5.3 Codes & Standards ...................................................................................................... 10

2 JACKET STRUCTURE DESIGN BASIS............................................................................... 12 2.1 INTRODUCTION ......................................................................................................................... 12 2.2 MODES OF PLATFORM OPERATION....................................................................................... 12 2.3 DETAILING FOR EASE OF FABRICATION AND INSPECTION ............................................... 13 2.4 ANALYTICAL PROCEDURES .................................................................................................... 14

2.4.1 General Outline ............................................................................................................ 14 2.4.2 Representative Topside Structure................................................................................ 14

2.5 CODES, STANDARDS, AND REGULATIONS BACKGROUND ................................................ 14 2.6 INTERFACES.............................................................................................................................. 15 2.7 ADDITIONAL DESIGN REQUIREMENTS .................................................................................. 15

2.7.1 Jacket and Pile Seamarking......................................................................................... 15 2.7.2 Air Gap ......................................................................................................................... 16 2.7.3 Foundation System ...................................................................................................... 16

3 JACKET STRUCTURE FUNCTIONAL REQUIREMENTS ................................................... 17 3.1 GENERAL OUTLINE................................................................................................................... 17 3.2 MATERIAL SPECIFICATION ...................................................................................................... 17

3.2.1 Structural Steel............................................................................................................. 17 3.2.2 Additional Steel Material Requirements....................................................................... 17 3.2.3 Neoprene Liners........................................................................................................... 17 3.2.4 Grouting Lines .............................................................................................................. 18 3.2.5 Bolted Connection........................................................................................................ 18 3.2.6 Anodes ......................................................................................................................... 18 3.2.7 Riser Pipe Material ....................................................................................................... 18

3.3 CORROSION PROTECTION...................................................................................................... 18 3.3.1 Cathodic Protection...................................................................................................... 18 3.3.2 Paint System ................................................................................................................ 18 3.3.3 Anti-fouling Paint .......................................................................................................... 18 3.3.4 Permanent Flooded Members...................................................................................... 19 3.3.5 Corrosion Allowances .................................................................................................. 19

3.4 FABRICATION SPECIFICATION................................................................................................ 19 3.5 PASSIVE FIRE PROTECTION ................................................................................................... 19



4 JACKET STRUCTURE DESIGN DATA................................................................................ 20 4.1 GENERAL OUTLINE................................................................................................................... 20

4.1.1 Service Life................................................................................................................... 20 4.1.2 Field Layout and Platform Orientation.......................................................................... 20

4.2 FOUNDATION DATA .................................................................................................................. 20 4.3 ENVIRONMENTAL DATA ........................................................................................................... 20

4.3.1 Metocean Conditions.................................................................................................... 20 4.3.2 Marine Growth.............................................................................................................. 24 4.3.3 Water Depth ................................................................................................................. 24

4.4 WELL SLOT & APPURTENANCE DATA.................................................................................... 24 4.4.1 General......................................................................................................................... 24 4.4.2 Conductor Slots............................................................................................................ 25 4.4.3 Caissons....................................................................................................................... 25 4.4.4 J-tubes.......................................................................................................................... 26 4.4.5 Additional Appurtenances ............................................................................................ 27 4.4.6 Future Appurtenance Allowances ................................................................................ 28 4.4.7 Risers ........................................................................................................................... 28

5 JACKET STRUCTURE ANALYSIS PHILOSOPHY.............................................................. 32 5.1 GENERAL.................................................................................................................................... 32 5.2 MINIMUM ANALYSIS REQUIREMENTS.................................................................................... 32 5.3 BACKGROUND........................................................................................................................... 32 5.4 WEIGHT CONTROL.................................................................................................................... 33 5.5 INPLACE ANALYSES ................................................................................................................. 33

5.5.1 General......................................................................................................................... 33 5.5.2 Redundancy ................................................................................................................. 33 5.5.3 Pushover Analysis........................................................................................................ 33 5.5.4 On-Bottom Stability ...................................................................................................... 33

5.6 FOUNDATION ANALYSIS .......................................................................................................... 34 5.6.1 Temporary Foundations ............................................................................................... 34 5.6.2 Permanent Foundations............................................................................................... 34

5.7 DYNAMIC & FATIGUE ANALYSIS ............................................................................................. 35 5.8 SEISMIC ANALYSIS ................................................................................................................... 35 5.9 SHIP IMPACT.............................................................................................................................. 37 5.10 FABRICATION AND LOAD-OUT ................................................................................................ 37 5.11 JACKET TRANSPORTATION ANALYSIS.................................................................................. 37 5.12 JACKET UPENDING AND INSTALLATION ANALYSIS............................................................. 38 5.13 APPURTENANCE ANALYSIS & DESIGN .................................................................................. 38 5.14 DECOMMISIONING ANALYSIS ................................................................................................. 38

6 PRODUCTION RISERS......................................................................................................... 40 6.1 GENERAL.................................................................................................................................... 40 6.2 RISER AND SUPPORTS CONFIGURATION............................................................................. 40

6.2.1 Nominal Size ................................................................................................................ 40 6.2.2 Configuration ................................................................................................................ 40 6.2.3 Supports ....................................................................................................................... 41

6.3 MATERIALS ................................................................................................................................ 41 6.4 CORROSION PROTECTION...................................................................................................... 41



6.5 ANALYSIS AND DESIGN............................................................................................................ 41 6.5.1 General......................................................................................................................... 41 6.5.2 In-service Load Conditions........................................................................................... 42 6.5.3 Fatigue Conditions ....................................................................................................... 42

6.6 DESIGN BASIS DATA................................................................................................................. 42 6.6.1 Design Life ................................................................................................................... 42 6.6.2 Temperature and Pressure .......................................................................................... 42 6.6.3 Fluid Composition......................................................................................................... 43 6.6.4 Flow Rates ................................................................................................................... 43 6.6.5 Operating Cycles.......................................................................................................... 43

7 WELLHEAD ACCESS DECK PERFORMANCE CRITERIA................................................. 45 7.1 FUNCTION .................................................................................................................................. 45

7.1.1 Installation Phase......................................................................................................... 45 7.1.2 Jack-Up Phase............................................................................................................. 45 7.1.3 WAD Removal.............................................................................................................. 45

7.2 LAYOUT ...................................................................................................................................... 46 7.3 FORM OF ATTACHMENT TO JACKET...................................................................................... 46 7.4 BASIS OF DESIGN ..................................................................................................................... 47 7.5 NAVIGATIONAL AIDS................................................................................................................. 47

8 TOPSIDE STRUCTURE INTERFACE................................................................................... 48 8.1 GENERAL.................................................................................................................................... 48

8.1.1 Installation .................................................................................................................... 48 8.1.2 Future Developments................................................................................................... 48 8.1.3 Sea Escape Ladders.................................................................................................... 48

8.2 TOPSIDE HOOK-UP OVERVIEW............................................................................................... 48 8.2.1 Appurtenance Hook-up ................................................................................................ 48 8.2.2 Levelling of Topside Stab-in Points.............................................................................. 48 8.2.3 Temporary Top of Leg Seal ......................................................................................... 49

8.3 AIR GAP PROVISIONS............................................................................................................... 49 8.4 TOPSIDE STRUCTURAL INTERFACE ...................................................................................... 49 8.5 OUTLINE TOPSIDES DATA ....................................................................................................... 49

8.5.1 Topside Mass and Weight............................................................................................ 49 8.5.2 Topside Environmental Loading................................................................................... 50

9 SUBSEA DRILLING TEMPLATE INTERFACE .................................................................... 51 9.1 FUNCTION .................................................................................................................................. 51 9.2 LAYOUT ...................................................................................................................................... 51 9.3 DOCKING PILES DATA .............................................................................................................. 51 9.4 DOCKING PILE RECEPTACLES................................................................................................ 51

9.4.1 Corrosion Protection..................................................................................................... 51 9.4.2 Fabrication and Tolerances.......................................................................................... 51

10 JACK-UP DRILLING PLATFORM INTERFACE................................................................... 54 10.1 NOMINATED RIG........................................................................................................................ 54 10.2 CONDUCTOR SLOT ACCESS ................................................................................................... 54 10.3 CONDUCTOR SLOT DESIGN .................................................................................................... 54 10.4 JACK-UP LOADING .................................................................................................................... 54



10.5 FOUNDATION LOADING............................................................................................................ 54

11 WEST FRANKLIN JACKET STRUCTURE PROPOSED OUTLINE CONCEPT .................. 57 11.1 OUTLINE ..................................................................................................................................... 57 11.2 MAJOR DEVIATIONS FROM EXISTING WHP STRUCTURES ................................................ 57 11.3 WEIGHT REPORT ...................................................................................................................... 58

12 EXISTING ELGIN / FRANKLIN WELLHEAD STRUCTURES .............................................. 59 12.1 FRANKLIN WHP GENERAL DESCRIPTION.............................................................................. 59 12.2 ELGIN WHP GENERAL DESCRIPTIONS .................................................................................. 59 12.3 IMPROVEMENTS IN DESIGN REQUIRED................................................................................ 59

12.3.1 Fatigue lives on Hot Nodes .......................................................................................... 59 12.3.2 Flooded Member Detection.......................................................................................... 59

12.4 LESSONS LEARNT..................................................................................................................... 59 12.5 FRANKLIN WHP FACTSHEET ................................................................................................... 60

APPENDIX 1: FIELD LAYOUT .................................................................................................... 64

APPENDIX 2: PROPOSED JACKET STRUCTURE OUTLINE CONCEPT DRAWINGS ........... 67

APPENDIX 3: PROPOSED JACKET STRUCTURE TEMPLATE WEIGHT REPORT............... 69

APPENDIX 4: JACK-UP PLATFORM DATA............................................................................... 72

APPENDIX 5: FRANKLIN WELLHEAD TOPSIDE STRUCTURAL DRAWING LIST ................ 77

APPENDIX 6: EXISTING TEPUK FRANKLIN WELLHEAD JACKET STRUCTURE DRAWING LIST .............................................................................................................................................. 78

LIST OF FIGURES

Figure 1-1: Elgin 'A' Jacket Installation Aug '97...................................................................................... 7 Figure 2-1 - Precedence of Codes, Standards, and Regulations.......................................................... 14 Figure 4-1: Conceptual Field Layout – For Information Only................................................................. 29 Figure 4-2: Platform Location & Orientation – To Be Confirmed by CLIENT ........................................ 30 Figure 4-3: Well Slot & Appurtenance Layout – Ref WF Drawing “WFA-JAC-00-S-GA-10030-001”... 31 Figure 5-1: Seismic Response Spectrum ............................................................................................. 36 Figure 7-1: Example of WAD structure Prior to Deck Removal............................................................ 46 Figure 9-1: Docking Pile Plan Receptacle Location – Ref WFA-JAC-00-S-GA-10023-001 (Appendix 2)53 Figure 10-1: Proposed Initial Jack Up Platform Location (North Face) - prior to Jacket Structure Installation.............................................................................................................................................. 56 Figure 12-1: Franklin 'A' Jacket Structure Perspective with Wellhead Access Deck ........................... 61 Figure 12-2: Elgin 'A' Jacket Structure Perspective with Wellhead Access Deck ................................ 62

LIST OF TABLES

Table 2-1: In-Situ Platform Configuration Progression ......................................................................... 13 Table 3-1: Corrosion Allowances........................................................................................................... 19 Table 4-1: Location & Orientation ......................................................................................................... 20 Table 4-2: 1 yr Return Directional Wave Loading – Fugro 2009 .......................................................... 21 Table 4-3: 100 yr Return Directional Wave Loading – Fugro 2009 ...................................................... 21 Table 4-4: 1 yr Return Independent Current – Fugro 2009 ................................................................... 22 Table 4-5: 100 yr Joint Probability Current (with wave) – Fugro 2009 ................................................. 23



Table 4-6: Extreme water levels to LAT – Fugro 2009 ......................................................................... 24 Table 4-7: Marine Growth Profile........................................................................................................... 24 Table 4-8: Water Depth Data................................................................................................................. 24 Table 4-9: Conductor Slot Data ............................................................................................................. 25 Table 4-10: Caisson Requirements ....................................................................................................... 26 Table 4-11: J-Tube Requirements ......................................................................................................... 27 Table 4-12: Future Appurtenance Provision .......................................................................................... 28 Table 6-1: Fluid Composition............................................................................................................... 43 Table 6-2: Water Composition .............................................................................................................. 43 Table 6-3: Flow Rates........................................................................................................................... 43 Table 8-1: Topside Installation Pin Design Data .................................................................................. 48 Table 8-2: Air Gap Provisions............................................................................................................... 49 Table 8-3: Topside Interface Data ......................................................................................................... 49 Table 8-4: Topside Gross Not-To-Exceed Weight Phase Data............................................................. 50 Table 8-5: Topside Environmental Parameters ..................................................................................... 50 Table 10-1: RGV Jack-Up Platform Spud Can Reactions .................................................................... 55 Table 11-1: Template Weight Summary ............................................................................................... 58 Table 12-1: Franklin 'A' Factsheet ........................................................................................................ 60

TEMPORARY LIST OF HOLDS

Hold No. 5 – Gangway support requirements on WAD to suit Jack-Up Platform

Hold No. 8 – Confirmed Docking Pile Diameter

Hold No. 17 – Site Specific Soils Data

Hold No. 18 – Site Specific Metocean Data

Hold No. 19 – Riser Size and diameter



1 INTRODUCTION

1.1 BACKGROUND The West Franklin field is adjacent to the western margin of the Franklin Field in the Central Graben area of the North Sea. The structure straddles Blocks 29/4d and 29/5c. West Franklin is an ultra HP/HT field where the reservoir conditions are more severe than in the rest of existing Elgin/Franklin field.

It is the intention of TEPUK to start drilling wells with a jack-up platform at the West Franklin location ahead of the jacket installation. To this end, a subsea drilling template, by others, shall be installed to define well alignment. The subsea template shall incorporate docking piles over which the jacket structure will locate during installation.

To minimise the risks associated with tie-back of the ultra HP/HT wells, TEPUK wish to expedite the installation of the jacket as soon as practicable and therefore propose the use of the existing TEPUK wellhead structures within the Elgin/Franklin Field as design templates. To this end, TEPUK have developed an outline concept of the jacket reflecting some of the changes required for the West Franklin Development. The differences are outlined in section 11. The data associated with the Franklin Wellhead Platform ‘A’ and Elgin Wellhead Platform ‘A’ is presented in section 12.

Figure 1-1: Elgin 'A' Jacket Installation Aug '97

In-service experience gained from the operation and inspection of this design has highlighted some improvements over the original Franklin and Elgin WHP designs, which are highlighted within this specification.

The adoption of an alternative design concept is acceptable provided the solution demonstrates an improvement in performance to the Jacket template design and can meet or bring forward the installation date of that of the Jacket template design.

In terms of performance, TEPUK welcome designs which shall;



• Reduce operating expenditure during the life of the field,

• Provide strength and durability to permit the maximum operational and functional flexibility to cater for future developments,

• Improve and reduce in-service inspection requirements by

o provision of a fully non-flooded bracing system

o provision of connection details that can be readily inspected

o provision of good connection details and structural framing that maximises fatigue lives

• Facilitate the eventual de-commissioning and removal of the platform.

1.2 PURPOSE This specification outlines the minimum technical requirements for the design of the following components associated with the Wellhead Platform ‘A’ Jacket Structure;

• West Franklin jacket structure, pre-fitted appurtenances, future appurtenance provision & piled foundations

• Wellhead Access Deck

• Interfaces with:

o Docking Piles utilised for the jacket installation

o Topside installation pins utilised for protecting the wellheads during lifting operations

o Topside Structure including the Appurtenance layout

o Conductor Slot arrangement

o Drilling Jack-up Platform

In addition to defining the functions of the as-installed jacket, this document also specifies statutory requirements and certain engineering preferences required by TEPUK.

An outline design concept for the jacket is presented, section 11, to expedite the installation as soon as practicable. This is aligned to the existing TEPUK wellhead structures within the Elgin / Franklin Field, incorporating proven appurtenance support details and jacket framing.



1.3 ABBREVIATIONS

BOS Bottom of Steel NUI Normally Unmanned Installation

CoG Centre of Gravity PUQ Production, Utilities, and Quarters

DWS Dead Weight Support ROV Remote Operated Vehicle

FOF Face of Flange TEPUK Total Exploration & Production United Kingdom

HISC Hydrogen Induced Steel Cracking TOS Top of Steel

HLV Heavy Lift Vessel VIV Vortex Induced Vibration

HSE Health & Safety Executive WAD Wellhead Access Deck

LAT Lowest Astronomical Tide WHP Wellhead Platform

1.4 DEFINITIONS For the purposes of this specification the following words have specific meanings

SHALL To be understood as mandatory to comply with the requirements of this specification

SHOULD To be understood as strongly recommended to comply with the requirements of this specification

WILL Used in conjunction with an action by CONTRACTOR

MAY Used when provision is discretionary

1.5 REFERENCES The following documents are referenced in this specification or will be used during the design of the jackets.

1.5.1 Design Information References 1. “Metocean Design Criteria for the Central Graben Area - Shearwater, UK Block 22/30c, & Puffin”,

Volume 1 Main Report, PARAS Report no. 0037, Project OC5020, Sept 1995.

2. “Engineering and Soil Parameters Report, Franklin Site Soils Investigation, Block 29/05, UK Sector, North Sea”, Report no. 73524-3, Contract no. CA.9249, Rev 02 13/6/97

3. Franklin Wellhead As-Built Topside Drawings, See Tender No. 00264 Exhibit E

4. West Franklin Proposed Jacket Structure Outline Concept Drawings, See Tender No. 00264 Exhibit E

5. Existing Franklin Wellhead Jacket Drawings, See Tender No. 00264 Exhibit E

6. West Franklin Site Soil Characteristic Data – HOLD No. 17

7. West Franklin Site 2009 Metocean Data – HOLD No. 18



1.5.2 Total General Specifications

Reference Title

GS EP STR 001 Weight monitoring and weighing offshore units

GS EP STR 101 Design of Offshore jacket and subsea structures

GS EP STR 103 Design and fabrication of skids and equipment supporting structures

GS EP STR 201 Materials for Offshore Steel Structures

GS EP STR 202 Cast Materials for Steel Structures

GS EP STR 203 Forged Materials for Steel Structures

GS EP STR 301 Fabrication of Offshore Steel Structures

GS EP STR 401 Loadout, Seafastening, transportation and installation of offshore structures

GS EP STR 431 Installation of piles for offshore structures, Driven Piles

GS EP STR 432 Installation of piles for offshore steel structures Drilled and Grouted Piles

GS EP ECI 001 Reference Levels for Offshore Platforms

GS EP COR 104 Material Selection and Corrosion Control For Sea Water Lift Pump and Water Discharge Caissons

GS EP COR 201 Supply of Sacrificial Anodes

GS EP COR 350 External Protection of Offshore and Coastal Structures and Equipment by Painting

GS EP PLR 242 Fabrication of Duplex and Super Duplex Stainless Steel in Seamless Pipes for Pipelines

1.5.3 Codes & Standards

Reference Title

ISO 19900 Petroleum and natural gas industry – General Requirements for offshore structures

ISO 19901-1 Petroleum and natural gas industry – Specific requirements for offshore structures – Part 1: Metocean design and operating conditions

ISO 19901-2 Petroleum and natural gas industry – Specific requirements for offshore structures – Part 2: Seismic design procedures and criteria

ISO 19901-4 Petroleum and natural gas industry – Specific requirements for offshore structures – Part 4: Geotechnical and foundation design considerations

ISO 19901-5 Petroleum and natural gas industry – Specific requirements for offshore structures – Part 5: Weight control during engineering and construction

ISO 19901-6 Petroleum and natural gas industry – Specific requirements for offshore structures – Part 6: Marine Operations



Reference Title

ISO 19902 Petroleum and natural gas industry – Fixed Steel Offshore Structures

API RP2A LRFD Recommended Practice for Planning and Constructing Fixed Offshore Platforms Load and Resistance Factor

API RP2A WSD Recommended Practice for Planning and Constructing Fixed Offshore Platforms Working Stress Design

AISC Steel Construction Manual



2 JACKET STRUCTURE DESIGN BASIS

2.1 INTRODUCTION The jacket design shall comply with the overall design basis of this section, the performance criteria outlined in section 3, and the structural data outlined in section 4. Jacket structure analysis shall be completed to the philosophy of section 5.

The key reference document shall be taken as Total Specification GS EP STR 101 “Design of Offshore jacket and subsea structures”.

2.2 MODES OF PLATFORM OPERATION The design of the West Franklin wellhead jacket structure shall account for all envisaged modes of service throughout field life. The changes in configuration of the in-situ platform are presented in Table 2-1.

It is intended that the jacket structure is installed after at least 2 wells, up to a maximum of 5, have been pre-drilled through a subsea template, by others.

Following jacket installation, the jacket shall act as the template for further drilled wells. A Wellhead Access Deck (WAD) will provide access to the wellheads and shall facilitate completion of the wells prior to the installation of the permanent topside structure.

It is intended that the topside structure will be installed after a minimum of 3 wells in total have been drilled, up to a maximum of 6. Immediately following topside installation, hook up of appurtenances will be carried out to enable operation of the platform. The drilling activity will then continue in cantilever mode from the Jack-up Drilling Rig over the structure until a maximum of 12 no. producing wells are completed.

At any time during the service life, further wells may be drilled (up to a total of 12), or the existing wells may require maintenance. This will be done using a jack-up platform operating in cantilever mode.

In addition, future allowance may be developed in terms of weight and additional appurtenances.

Phase Description Duration

1 Temporary Phase Following lift installation and foundation piling, jacket structure will have the Wellhead Access Deck (WAD) in place at the top of the jacket, and appurtenances will be in recessed transportation position.

Jack-up structure will be working in cantilever mode over the structure and the number of completed conductors and tiebacks will increase from initially 0 (zero) up to a maximum of 5.

Up to a maximum of 3 years

2 Topside Installation Phase

The WAD will be removed.

The topside structure and any ancillary structures will be installed.

Short Duration

3 Topside Hook-Up Phase

Caissons will be pulled up to the hook-up position with dead weight transferred to the topside structure where appropriate.

J-tube spool pieces will be installed and umbilicals/cables will be pulled in.

Interfield pipelines will be connected to the risers subsea.

Riser spool pieces will be installed and connected to topside pipework.

Up to 3 months



Phase Description Duration

4a Operating Phase Operating platform will work with and without the Jack-up platform in cantilever mode alongside.

Up to 12 conductors will be completed

Up to platform design life

4b Future Operating Phase

Additional future topside weight added.

Additional future riser caisson and J-tube caisson installed.

Up to 12 conductors will be completed

Up to platform design life

Table 2-1: In-Situ Platform Configuration Progression

2.3 DETAILING FOR EASE OF FABRICATION AND INSPECTION The contractor shall ensure that the design of the jacket incorporates details which are simple and robust. Overall design of the jacket as an efficient structure should be considered a function not only of optimised member design, but of details of their interconnections which favour automatic member design and allow good access for inspection. For joints that are critical to the overall strength and stability of the jacket, there will be ready access to welds for inspection during the service life of the platform. In designing and detailing the jacket, the following principles of good design shall be adopted wherever possible:

• Use of regular, repeatable details

• Use of continuous manufacture

• Minimise the range of material types and thicknesses

• Brace incident angles in the range of 40 to 50 degrees

• Minimum external temporary works

• Only incorporate into the permanent structure such temporary works as can be utilised for an in-place function

• Avoid, unless necessary, the use of internal ring stiffeners

• No overlapping joints

• Minimum use of post weld heat treatment

• Zero or single battered frames

• Only include bracings where the design shows them to be essential

• Use design, fabrication, and installation techniques which individually have a successful precedent

• Use of non-flooded bracing system which allows Flooded Member Detection techniques to be employed to detect through thickness cracks.

The Contractor shall aim for a “clean” structure with a view to maximising the tasks that can be accomplished by an ROV and therefore shall include the following features:

• Eliminating underwater attachments that could trap diver or ROV umbilicals.

• Configure nodes to allow close access for visual inspection by considering the angles and gaps between braces

• Avoid locating miscellaneous attachments, such as anodes and grout lines, close to the nodes

• Avoid locating regularly inspected nodes in or close to the splash zone



2.4 ANALYTICAL PROCEDURES

2.4.1 General Outline The contractor is required to demonstrate that all components of the jacket have been adequately designed and that all stresses are within allowable limits for all phases of the platform installation. The ruling structural design standard for the jacket shall be BS EN 19902, “Fixed Steel Offshore Structures”. However it is recognised that in practical terms, analysis shall be carried out to API RP2A LRFD. Local secondary steelwork design may be based on the working stress method using API RP2A-WSD / AISC WSD where appropriate.

All jacket primary structural analyses shall be based on proven and verified three dimensional finite element computer programs. In particular, the automatic generation of forces representing the action of waves and current on various elements of the structure shall have been calibrated against industry-accepted standards. The structure shall be modelled to include all significant components of the external loads applied to the structure and its response. Parts of the structure that are simplified in the modelling of the structure shall be analysed separately in more detail, giving due consideration to loads and deflections at the boundary with the global model.

In compiling the computer model of the jacket, careful consideration shall be given to the boundary conditions of the model, at the deck and the foundations. A simplified model of the deck correctly representing its stiffness and capable of applying topside loading, shall be included for the appropriate analyses. Similarly, pile foundation stiffness shall be modelled in a manner appropriate to the particular analysis. For the design of the piles themselves and the jacket structure adjacent to the mudline, an integrated non-linear pile-structure model shall be adopted.

Further details on the minimum requirements for jacket analysis are included in section 5.

2.4.2 Representative Topside Structure As the topside design is not mature at this time the TEPUK Franklin Wellhead Topside structure shall be adopted for the purposes of model stiffness and load transfer. Primary structural drawings of the topsides structure are included in Appendix 5.

For the purposes of mass distribution, section 8.5 outlines the Centre of Gravity of the main components.

2.5 CODES, STANDARDS, AND REGULATIONS BACKGROUND The order of precedence for applicable codes, standards and regulations etc shall be as per Figure 2-1. A full list of applicable specifications, design codes and standards is provided in section 1.4.

i) UK Acts of Parliament

ii) Regulations/Statutory Instruments

iii) Total Group HSE Policy

iv) Asset Specifications and Philosophies

v) Total E&P General Specifications

vi) Baseline Industry Standards – British, European and International

vii) Key Reference Documents (Industry bodies, Trade Associations, Institutes, etc)

Figure 2-1 - Precedence of Codes, Standards, and Regulations

In the event of conflict the user shall seek clarification from the appropriate Total Structural Technical Authority.

Notes:

i. Health and Safety at Work 1974 or Offshore Safety Act 1992 etc.

ii. PUWER, COSHH etc. European Directives are also embodied in UK law through SI’s.



iii. All Total Group corporate requirements such as HSE policy.

iv. Asset Specifications include Operational Integrity Assurance and Verification Schemes, which include Performance Standards for all Safety Critical Elements, these define the functionality, reliability and survivability requirements..

v. Total E&P General Specifications are available on CD.

vi. Baseline Industry standards include British, European and International organisations such as ISO, BSI, ANSI, API, ASME etc.

vii. Key reference documentation, which forms a breadth of industrial best practice. This includes design guides, recommended practices, rule books, guidance notes, codes of practice etc.

2.6 INTERFACES The design of the jacket shall ensure compatibility with the following interfaces;

• Topside Structure Interface, see section 8

o Stab-in elevation to be set to maintain air gap to topside structure

o Green material to be allowed for on legs to ensure offshore cut line can establish horizontal plane to support topsides

o Jacket design to account for support of guide pins to aid installation of topside structure over wellheads

o Positioning of risers, caissons and j-tubes as defined by the topsides layout

o Positioning of sea access ladders as defined by the topsides layout

• Subsea Drilling Template, see section 9

o Position and positional tolerance of template drilling slots

o Position and positional tolerance of docking piles

o Load interface with docking piles

o Installation clearance to template structure

• Jack-Up Platform, see section 10

o Consideration of pile interface with jack up platform spud cans

o Consideration of mudmat interface with disturbed seabed soils after jack-up spudcan removal

o Accessibility of the conductor slots from the nominated jack-up platform

o Load transfer between the jack-up platform and jacket structure during drilling

o Load transfer in running conductors and tie-backs through the jacket

2.7 ADDITIONAL DESIGN REQUIREMENTS

2.7.1 Jacket and Pile Seamarking The marking of the jacket shall assist an ROV or Diver on the approach to the jacket. The system of underwater markers identifies the main structure of the jacket and provides the initial position reference when approaching the jacket. All markers shall be positioned on the outside of the node and away from welds to facilitate clear viewing by the diver or ROV from normal approach routes and at a reasonable distance. Markers shall remain visible to divers and ROV over the full design life of the jacket. The use of agents shall ensure freedom from fouling by marine organisms over the field life, combined with the use of stable colorants should ensure that the marked surfaces will maintain their visibility.

The global marking system of underwater identification shall be identified in inspection identification drawings and shall comprise, as a minimum, the following:-

• Each leg/brace node and primary brace/brace node below the waterline shall be numbered. The numbering system shall identify the water depth and the gridline reference. For example, 28H4



would be the leg node at the -28m level at the junctions of rows H and 4, 38-H would be the ‘X’ node at the -38m level on row H and 58-4 would be the ‘X’ node at the -58m level on row 4

• Each pile sleeve shall be uniquely identified on the face of each sleeve and at each node, e.g. 90S1 would be the node of the pile sleeve S1 at the -90m level.

• Node identification is required at each major node and conductor plan bracing

• Jacket Leg Draught marks

• Jacket Leg identification at top of each leg. Note that these shall be located below the “green” material allowed for in topside levelling to ensure they remain following leg cutting

• Conductor Slot Identification at +8m

• J-tubes and Caisson identification marks

• Pile penetration marks

2.7.2 Air Gap The stab-in elevation shall be set by CONTRACTOR. Reference to sections 8.3 and 8.4 shall be made for relevant parameters to be considered.

For the purpose of setting the Air Gap to the topside lower level Bottom of Steel (BOS), the jacket shall be considered to be a Normally Unmanned Installation (NUI). This will allow adoption of the 1,000 year return period environmental conditions in derivation of the wave crest level. The wave crest level is provided in Table 4-6.

The stab-in point on the jacket legs shall be cut, by others, prior to topside installation within the “green” allowance to define a true horizontal plane at the required elevation.

Reference shall be made to Total specification GS EP ECI 001, “Reference Levels for Offshore Platforms” and GS EP STR 101 “Design of Offshore jacket and subsea structures”.

2.7.3 Foundation System The jacket shall be permanently supported off 4 no. single driven piles, fixed to the jacket pile sleeves by a grouted annulus.

Temporary support shall be provided by 4 no. mudmats local to the pile locations sized to provide sufficient factor of safety to overturning and sliding prior to stabbing, driving and grouting of piles. The settlement of the mudmats shall be evaluated and the result used in the determination of the jacket height to achieve the required air gap.

Reference shall be made to Total specification, GS-EP-STR-431 “Installation of piles for offshore structures, Driven Piles”.

Bottom termination of risers and j-tubes, and mudline framing, shall be set such that they do not settle into the mudline following jacket set down.

For the purposes of analysis a scour allowance will be allowed for equal to ½ the pile diameter.



3 JACKET STRUCTURE FUNCTIONAL REQUIREMENTS

3.1 GENERAL OUTLINE The jacket shall be an all welded steel space frame structure lift-installed by a heavy lift vessel and founded on tubular driven piles.

A drilling template structure shall be utilised to locate the jacket over the pre-drilled wells. The structure shall be installed with a wellhead access deck in place on the top of the jacket, see section 6.

The structure and foundation layout shall be suitable to interface with the nominated drilling platforms both with and without the topside structure having been installed.

3.2 MATERIAL SPECIFICATION

3.2.1 Structural Steel The detailed design of the jacket shall be based on nominal steel yield strengths.

Default steel grade shall be S355. Higher yield steel shall only be used with TEPUK approval and shall not be used at nodes.

The structural materials used for permanent inclusion shall comply with the following specifications where appropriate;

• Total Specification GS EP STR 201, “Materials for Offshore Steel Structures”.

• Total Specification GS EP STR 202, “Cast Materials for Steel Structures”.

• Total Specification GS EP STR 203, “Forged Materials for Steel Structures”.

3.2.2 Additional Steel Material Requirements The following additional requirements shall be met.

Additional Tests

In the event that the steels furnished appear to exhibit properties not normally attributed to the steel grades specified for inclusion in the structure, although allowable under the respective Industry Standard used (such as extremely high carbon content, brittleness, and other indications of poor weldability and/or ductility), TEPUK will retain the right to require additional test results to insure that the steels used are acceptable for inclusion in the structure. Cost of these tests shall be borne by CONTRACTOR.

Imperfections and Repairs

The repair of all defects shall be subject to COMPANY APPROVAL. Laminations extending into the face or bevel of a plate or tubular are unacceptable. Material containing such defects shall be cut back until all laminations are removed.

CONTRACTOR shall be allowed only one opportunity to repair a defect. A repeat of the defect shall be cause for rejection. COMPANY reserves the right to require replacement after a second failure to pass.

Reject Steel

All structural steel shall be new and manufactured to the grade and for the use intended. Steel shall be free from defects, excessive mill scale, and rust. No reject or salvaged steel shall be allowed for the WORK. Steel which is reclassified “structural” after being rejected for other service is specifically prohibited.

3.2.3 Neoprene Liners The inner lining of pre-fitted riser, caisson and j-tube guides shall incorporate a 27mm thick ribbed polychloroprene liner with a hardness defined by IRHD65. These shall be fully bonded to the inner surfaces of the guides to procedure approved by COMPANY.



3.2.4 Grouting Lines Piping systems installed on the Jacket for grouting shall be constructed in accordance with the requirements of ANSI B31.3. Piping materials shall be new and free from defects and shall be manufactured in accordance with the following Industry Standards and as shown on the AFC Drawings:-

• Pipe API 5L Gr. B

• Weld Fittings ANSI B 16.9; ASTM A234 WPB

• Thread Fittings ANSI B 16.11

• Bolts ATSM A193 Gr B7

• Nuts ASTM A194 Gr 2H

• Flanges ANSI B 16.5

3.2.5 Bolted Connection Bolting connection materials shall comply with Total Specification GS EP STR 201, “Materials for Offshore Steel Structures”.

3.2.6 Anodes Anode materials shall comply with Total Specification GS EP COR 201 “Supply of Sacrificial Anodes”.

3.2.7 Riser Pipe Material See section 6 for riser pipe material.

3.3 CORROSION PROTECTION The corrosion of all steelwork in the atmospheric, splash and submerged zones of the jacket, the piled foundation, the risers and conductors must be inhibited using the cathodic protection system combined with paint, wrap plates or sacrificial steel so that in-service maintenance is minimised. It can be assumed that the conductors are painted.

3.3.1 Cathodic Protection The attachment of anodes to the primary structure shall be designed to resist all foreseeable static and fluctuating loads, including those caused by waves and current and by the driving of piles.

Design of the anodes shall comply with Total Specification GS EP COR 100 “Design of Cathodic Protection of Offshore Structures”

Provision shall be allowed for in the anode design to account for potential future appurtenances as outlined in section 4.4.6. It shall be assumed that there is no connectivity to the subsea template or installation docking guides.

3.3.2 Paint System The painting system shall comply with Total Specification GS EP COR 350 “External Protection of Offshore and Coastal Structures and Equipment by Painting”.

The finishing colour shall be to RAL 1003, “Signal Yellow”

3.3.3 Anti-fouling Paint Anti-fouling paint shall be applied to the following areas;

• Internal surfaces of future guides between +1.5m to -40m

• Internal surface of the sewage caisson to a height not less than one diameter from the bottom of the caisson

• Internal surface of Seawater and Firewater caissons to a height not less than one diameter from the bottom of the caisson

• All faces of diver/debris protection guard at the bottom of the Seawater and Firewater caissons



The anti-fouling paint shall be of an active biocide type rather than solely rely on a slick surface finish.

3.3.4 Permanent Flooded Members Internal corrosion in permanently flooded members must be inhibited using a suitable biocide, oxygen scavenger and control of any ingress of oxygenated water.

Those members subsea designed to be flooded shall be fully flooded. The jacket legs shall be flooded to the sea water level. The legs shall be temporarily covered by a sealing cap cover following jacket installation and will be permanently sealed by installation of the permanent topside structure

3.3.5 Corrosion Allowances Corrosion allowances for the jacket and appurtenances are shown in the table below, for all other items reference shall be made to Total Specification GS EP STR 101 “Design of Offshore jacket and subsea structures”.

Corrosion Allowance (mm)

Item Atmospheric Zone Splash Zone Submerged

Zone

Legs (External) 3 6 -

Legs (Internal) - - 3 (Note 3)

Braces - 6 (Note 1) -

J Tubes (External) 3 6 (Note 2) -

J Tubes (Internal) - - 0.5 (Note 4)

Caissons (External) 3 6 (Note 2) -

Caissons (Internal) - - 3

Risers (External) See section 6

Table 3-1: Corrosion Allowances

Notes:

1) A reduced corrosion allowance for braces in the splash zone is based on an adequate level of brace redundancy (to be confirmed)

2) A reduced corrosion allowance for caissons and J-tubes is based on the application of a high integrity coating system to caissons and j-tubes and the low risk of mechanical damage, as these appurtenances are within the confines of the jacket

3) This corrosion allowance is to be applied to the internal surface of any freely flooded member

4) This corrosion allowance is to accommodate for the loss of wall thickness over a maximum of 2 years prior to the umbilical being pulled and the j-tubes being sealed

3.4 FABRICATION SPECIFICATION Fabrication shall comply with Total Specification GS EP STR 301, “Fabrication of Offshore Steel Structures”.

3.5 PASSIVE FIRE PROTECTION There is no requirement for additional passive fire protection coatings on the jacket structure.



4 JACKET STRUCTURE DESIGN DATA

This section details the design data associated with the jacket structure.

4.1 GENERAL OUTLINE

4.1.1 Service Life The service life of the structure shall be 35 years.

4.1.2 Field Layout and Platform Orientation See Table 4-1 for location and orientation data. These locations are approximate and are to be confirmed by TEPUK. Reference shall be made to Figure 4-1and Figure 4-2 for further clarity.

Easting 426 922

Northing 6 313 550

Platform North 48 deg to True North

Table 4-1: Location & Orientation

4.2 FOUNDATION DATA Soil characteristic site specific foundation data shall be made available in reference 6 when available.

At this time, preliminary design information is included, in the form of a soils investigation report for the adjacent Franklin WHP Location, reference 2. This was carried out in 1997 by Fugro prior to installation of the Franklin Jacket.

TEPUK experience of actual initial settlements versus predicted in the Elgin / Franklin area shall be utilised in predicting mudmat settlement

4.3 ENVIRONMENTAL DATA

4.3.1 Metocean Conditions At this time, the original Elgin/Franklin metocean design criteria, Reference 1, shall be used as the basis for the environmental loading. This report covers Block 29-C, which was utilised for the original wellhead platform developments. Since that time, the 100 year return storm event and extreme water levels have been reassessed. These are presented in Table 4-2 through to Table 4-6. All other metocean data shall be sourced from the original metocean report.

When available, the original report and Table 4-2 through to Table 4-6 will be superseded by site specific updated design metocean information, Reference 7. It is envisaged that all data will be not exceed that which is provided at this time.



Associated Period Range

(sec)

Direction

(from)

Maximum Wave Height

(m)

Lower Upper

North 16.1 10.4 18.1

North-East 9.4 8.2 16.1

East 13.0 9.5 17.3

South-East 14.0 9.8 17.6

South 12.7 9.4 17.2

South-West 13.7 9.7 17.5

West 15.4 10.3 18.0

North- West 16.1 10.4 18.1

Table 4-2: 1 yr Return Directional Wave Loading – Fugro 2009

Associated Period Range

(sec)

Direction

(from)

Maximum Wave Height

(m)

Lower Upper

North 25.1 12.7 20.0

North-East 14.7 10.0 17.8

East 20.3 11.6 19.1

South-East 21.8 11.9 19.4

South 19.7 11.4 19.0

South-West 21.3 11.8 19.3

West 24.0 12.5 19.8

North- West 25.1 12.7 20.0

Table 4-3: 100 yr Return Directional Wave Loading – Fugro 2009



The 1 year return independent current is present in Table 4-4.

DIRECTION (towards) – m/s Depth

(m) N NE E SE S SW W NW

0.0 0.54 0.47 0.48 0.57 0.57 0.51 0.31 0.42

10.0 0.54 0.47 0.48 0.57 0.57 0.51 0.31 0.42

20.0 0.54 0.47 0.48 0.57 0.57 0.51 0.31 0.42

30.0 0.54 0.47 0.48 0.57 0.57 0.51 0.31 0.42

40.0 0.54 0.47 0.48 0.57 0.57 0.51 0.31 0.42

50.0 0.53 0.46 0.47 0.57 0.57 0.50 0.30 0.41

60.0 0.51 0.44 0.45 0.55 0.55 0.48 0.29 0.40

70.0 0.49 0.42 0.43 0.52 0.52 0.46 0.28 0.38

80.0 0.45 0.39 0.39 0.48 0.48 0.42 0.26 0.35

90.0 0.36 0.31 0.32 0.39 0.39 0.34 0.21 0.28

92.0 0.31 0.27 0.27 0.33 0.33 0.29 0.18 0.24

Table 4-4: 1 yr Return Independent Current – Fugro 2009

The 100 year joint probability current associated with the 100 year return wave is presented in Table 4-5.



DIRECTION (towards) – m/s Depth

(m) N NE E SE S SW W NW

0.0 0.24 0.22 0.25 0.32 0.32 0.17 0.14 0.20

10.0 0.24 0.22 0.25 0.32 0.32 0.17 0.14 0.20

20.0 0.24 0.22 0.25 0.32 0.32 0.17 0.14 0.20

30.0 0.24 0.22 0.25 0.32 0.32 0.17 0.14 0.20

40.0 0.24 0.22 0.25 0.32 0.32 0.17 0.14 0.20

50.0 0.24 0.22 0.25 0.31 0.31 0.16 0.14 0.20

60.0 0.23 0.21 0.24 0.30 0.30 0.16 0.13 0.19

70.0 0.22 0.20 0.23 0.29 0.29 0.15 0.13 0.18

80.0 0.20 0.19 0.21 0.27 0.27 0.14 0.12 0.17

90.0 0.16 0.15 0.17 0.22 0.22 0.11 0.10 0.14

92.0 0.14 0.13 0.14 0.18 0.18 0.10 0.08 0.12

Table 4-5: 100 yr Joint Probability Current (with wave) – Fugro 2009



The extreme water level presented in Table 4-6 is derived from the sum of the independent extreme crest height and the independent extreme total water level, which itself accounts for joint occurrence of tidal level and surge height.

Return Period Extreme Water Level to LAT

(m)

100 year 17.83m

1,000 year 20.63m

10,000 year 23.31m

Table 4-6: Extreme water levels to LAT – Fugro 2009

4.3.2 Marine Growth The marine growth profile shall be taken as per Table 4-7.

Depth (ref. LAT) Thickness

(mm)

From +4m to -6m 30

From -6m to -20m 85

From -20m to -50m 50

From -50m to seabed 45

Table 4-7: Marine Growth Profile

4.3.3 Water Depth The water depth information as per Table 4-8 shall be adopted, reference should be made to Table 8-2 for additional allowances to consider in design,

Water Depth to LAT 92.4m

– To be Confirmed by

CLIENT

Table 4-8: Water Depth Data

4.4 WELL SLOT & APPURTENANCE DATA

4.4.1 General The appurtenances and supports outlined in this section shall be accounted for in the jacket design. See section 5.13 for minimum design requirements for appurtenances and their supports.

Note that the conductors and future caissons only, are for supply by others. The guides for these shall be supplied and the loadings shall be accounted for in the global analysis.

The positioning (in plan) of the risers, caissons, and j-tubes as defined in this document result from preliminary deck layout studies undertaken by COMPANY’s contractor and are therefore defined interface data. Any adjustment to these positions shall require APPROVAL by COMPANY. The positioning (in plan) of



the conductor slots shall align with the performance criteria of section 10, with regards to jack-up platform access.

The layout of the well slots and appurtenances is outlined in Figure 4-3.

4.4.2 Conductor Slots Table 4-9 outlines the conductor slot requirements. All guide slots shall include conical guides above and below to facilitate potential conductor running or tiebacks operations.

See section 10 for performance criteria required for the conductor slot positions in relation to jack-up platform position.

Table 4-9: Conductor Slot Data

4.4.3 Caissons An outline of the caisson requirements is presented in Table 4-10.

Design of the caissons shall take due consideration of Total Specification, GS EP COR 104, Material Selection and Corrosion Control for Sea Water Lift Pump and Water Discharge Caissons.

The following items shall be designed and provided as part of the caisson details:

• Weld neck flange and temporary blanking flange on top of the caisson

• Diver protection cage at the bottom of the caisson (Firewater and Seawater only)

• Covered vent slot on blind flange on top of the caisson

Firewater & Seawater Caissons

A constant section of 508mm diameter by 31.8mm wall thickness shall be used throughout the length of the caisson.

A temporary deadweight support shall be provided on the jacket. The dead weight shall be carried in bearing. The support shall be fixed in position via a bolted connection. This shall be accessible at the in air jacket plan level to aid hook-up activity. All surfaces that will be exposed following breaking of the bolted connection at the temporary deadweight support shall be adequately protected from corrosion.

All other supports shall act as guides, providing sufficient support in the hook-up and final position to the caisson. The guides will facilitate pull up of the caissons. To aid future caisson work, no external protrusions shall exist on the caisson which would prevent pulling the entire caisson up through all the guides.

To enable the pull-up operation of the caissons, 2 permanent padeyes shall be attached to the stiffener plates off the anchor flange. The outer diameter of the caisson anchor flange shall be minimised to aid pulling up through the topside structure and the padeyes shall not protrude beyond the outer diameter of the flange.

When determining the hook-up pulling load, for lift point and caisson design, resistance due to marine growth shall be taken into account in addition to the self weight of the caisson. Design of the lift points shall comply with Total Specification, GS EP STR 103 “Design and fabrication of skids and equipment supporting structures” as a minimum.

It shall be assumed that in-situ the caisson anchor flange shall also support a pump of the following weights:

• Dry weight of 3.0 tonnes

• Operating weight of 6.0 tonnes

Item Description

Conductors: 12 no. 30” Conductors, by others

Guides: 12 no. guide slots at plan elevations sufficient to maintain integrity of conductors.

• 48” inner diameter slots at in-air guides

• 42” inner diameter slots at subsea guides



Sewage Caissons

The sewage caisson shall be supported via support stubs off the jacket leg. The dead weight support shall be located as high up the structure as feasible, outwith the splash zone, all other supports shall acts as guides.

Function Requirements

1 no. 508mm (20”) caisson terminating at El.-24.5m in its final operational position.

The caisson shall be hooked up by lifting up into the topside structure so that the top of caisson (Face of Flange, FOF) is 0.7m above the top of the lower deck plate.

Seawater Lift

– SW1

In place, the caisson weight shall be supported off the underside of the Dead Weight Support (DWS) anchor flange at the Topside Lower Deck Top of Steel Elevation – see section 2.7.2 for basis of calculating elevation.

A sufficient number of guides shall be provided to maintain integrity of the caisson in all phases of the jacket operations.

Prior to topside installation, the caisson DWS shall be supported at the uppermost plan bracing level of the jacket. It is envisaged that this shall require an additional guide subsea to support the extended cantilever in the recessed caisson position.

1 no. 508mm (20”) caisson terminating at El.-24.5m in its final operational position.

The caisson shall be hooked up by lifting up into the topside structure so that the top of caisson (Face of Flange, FOF) is 0.7m above the top of the lower deck plate.

Firewater

– FW1

Support conditions shall be as per the seawater lift caisson.

1 no. 168.3mm (6”) caisson, terminating at El. -5.0m. The caisson shall terminate at a bolted flange at 2m below the top of jacket leg.

Hook up to the topsides shall be by flanged spools, designed and supplied by others

Sewage Caisson

– SD1

• DWS shall be provided in-air, outwith the splash zone

• Guided Supports off the leg shall be provided sufficient to maintain caisson integrity through all phases of jacket operation

Table 4-10: Caisson Requirements

4.4.4 J-tubes An outline of the J-tube requirements is presented in Table 4-11.

The J-tubes shall initially be sealed and dry with biocide corrosion inhibitor pre-installed inside them.

During the jacket installation the J-tubes shall free-flood via a subsea ROV friendly valve set to ‘open’ located near to the rip-out diaphragm location. Following installation the ROV friendly valve shall be closed. Each J-tube shall be provided with a rip-out diaphragm and a bellmouth at the bottom, and a blind flange with vent hole at the top. In between the blind flange and rip-out diaphragm, a messenger wire shall be pre-installed to assist in pulling in the power/service umbilical.

On the outer face of the rip-out diaphragm, a 4m long messenger wire shall be provided and the free end shall be secured on the top of the bellmouth for easy ROV/diver access.

In summary, the following items shall be provided as part of the J-tube details:

• 150# Raised Face Weld Neck Flange, and temporary blanking flange on top of the J-tube

• Bellmouth provided at the subsea termination

• Vent slot on blind flange on top of the caisson



• Messenger wire, greater than or equal to Safe Working Load of 10 tonne

• Temporary sealing diaphragm to fit and be securely held in bellmouth.

• An ROV operated flooding valve, must be open prior to rip-out of diaphragms.

• Biocide

Design of the J-tubes shall account for the pull in of the J-tube internals. This activity will be performed from the topsides. Pulling head data of those internals shall be assumed as follows;

• Design Pull Force for cables and umbilicals up to deck level = 30 tonne

• Pulling head diameter = 260mm

• Pulling head length = 1500mm long

• Umbilical Weight = To be Confirmed by CLIENT

• Umbilical Minimum Bend Radius = To be Confirmed by CLIENT

• Umbilical Stiffness = To be Confirmed by CLIENT

Minimum requirement for j-tubes bend ID are the following:

• 360mm for the 16” j-tube

• 299mm for the 12.75” j-tube

The dead weight supports and guides of the prefitted J-tubes shall be designed for the relevant tension force during pulling. Coefficient of dynamic friction between umbilical/cable and j-tube shall be taken as 0.3 for contact with wet steel.

The elevation of the subsea termination of the J-tubes shall take due consideration of expected mudmat settlement.


J-tubes 2 no. J-tubes are to be located on platform North face, east side:

• 406.4mm (16”) Utilities – “J1”

• 323.9mm (12 ¾ ”) Power – “J2”

Connection to topsides is to be by means of hook-up spool. The J-tubes shall terminate topsides 2m below the top of jacket leg.

Bell mouth plus blind flange required at entry point. Bellmouth shall exit at 45 degrees to the horizontal. The bellmouth elevation shall take due consideration of expected mudmat settlement.

The 16” Utility J-tube shall exit the jacket in plan at 10 degrees off platform North and shall continue sufficiently to clear the mudmat framing.

The 12 ¾” Power J-tube shall exit the jacket at 25 degrees off platform North and shall continue sufficiently to clear the mudmat framing.

Table 4-11: J-Tube Requirements

4.4.5 Additional Appurtenances Escape ladders shall be provided on diagonally opposite legs.

These shall provide alternative escape routes in both the temporary phase, from the WAD, and the permanent phase, from the topsides. It is envisaged that a temporary hook-up section will be required to connect onto the WAD. A spool piece, by others, will be required for the permanent configuration.

The ladders shall terminate at approximately elevation -3m.



4.4.6 Future Appurtenance Allowances Provision shall be made for the future allowances outlined in Table 4-12. Sufficient number of guides shall be provided on the jacket adequate to provide support to the carrier caissons. Due account of in-place conditions, vortex shedding and fatigue shall be made in setting the guide elevations. Dead Weight shall be carried topsides and shall be assumed to be included within the topside future allowance.

The guides shall not be lined with polychloroprene liners but shall be internally painted with anti-fouling paint. The topside layout, by others, will leave an installation corridor directly above.

The fabricator shall survey the as-built alignment of these guides and report this to CLIENT

For the purposes of analysis the future carrier caissons shall be considered running to the mudline.


1 no. 38” Riser Caisson, by others, ref R3 Future Appurtenances

1 no. 38” J-Tube Caisson, by others, ref J3

Table 4-12: Future Appurtenance Provision

4.4.7 Risers See section 6 for requirements on the 2 no. prefitted production risers, R1 & R2, and the associated supports.



Figure 4-1: Conceptual Field Layout – For Information Only



Figure 4-2: Platform Location & Orientation – To Be Confirmed by CLIENT



Figure 4-3: Well Slot & Appurtenance Layout – Ref WF Drawing “WFA-JAC-00-S-GA-10030-001”

HOLD N0. 19 – Riser Requirements



5 JACKET STRUCTURE ANALYSIS PHILOSOPHY

5.1 GENERAL The following section sets out the general analysis requirements for the West Franklin Jacket Structure.

The reference specification for the analysis shall be taken as Total Specification GS EP STR 101 – “Design of offshore jacket and subsea structures”

5.2 MINIMUM ANALYSIS REQUIREMENTS As a minimum, the following jacket analyses are to be undertaken:

• Inplace; Operating Conditions

• Inplace; Storm Conditions

• Redundancy

• Pushover

• Fabrication and Load-out

• Transportation

• Installation Lift & Upending

• On-Bottom Stability

• Dynamic & Fatigue Analysis

• Foundation Analysis (Piles & Mudmats)

• Pile Installation (stabbing and driveability analysis)

• Seismic Analysis

• Ship Impact & Post Damage Integrity

• Decommissioning (Jacket Removal)

• Appurtenance Design

As a general rule, whilst demonstrating the structural capabilities in relation to the design conditions, where appropriate, the results of the analysis shall also report the ultimate capacity of the structure to the loading scenario considered, (e.g. ship impact capacity, pushover).

5.3 BACKGROUND Appropriate analysis shall be carried out to demonstrate the structural capabilities of the jacket in response to the following Major Accident Hazards, where appropriate;

• Ship Collision

• Seismic Events

• Structural Failure

• Riser Leak

• Extreme Weather

The appropriate analysis techniques may include the following;

• Push over analysis

• Fatigue Analysis

• Redundancy Analysis

• Seismic analysis

• Ship Impact Analysis



5.4 WEIGHT CONTROL Weight Control shall be carried out to Total Specification, GS EP STR 001, “Weight monitoring and weighing offshore units”.

5.5 INPLACE ANALYSES

5.5.1 General The jacket and foundation shall be shown to be capable of safely resisting the forces imposed on the jacket structure and all appurtenances, by the maximum wave with a return period of 100 years. This shall act together with the joint probability current and independent wind. The position (or phase) of the passing wave giving maximum forces on the jacket (both in terms of overall horizontal shear and overturning effects) shall be determined and adopted for design. Due consideration shall be made for the maximum and minimum topsides weights. Similarly, the effects of the range of still water depths shall be taken into account. These forces shall act in combination with gravity loads with due consideration to the various stages of the jacket life. All action loads shall be factored in accordance with API RP2A LRFD as outlined in Total Specification GS EP STR 101 – “Design of offshore jacket and subsea structures”.

Non-linear foundations shall be considered.

In addition to this storm case, an operating condition reflecting 1 year return environmental conditions shall also be considered with appropriate use of LRFD load factors.

The analysis geometry model shall be developed considering the following minimum requirements:

• A comprehensive representation of all structural stiffness elements of the jacket, appurtenances and piles.

• Sufficient geometric information so that automatically generated hydrodynamic loads are properly computed.

• Non-linear pile-soil interaction effects considering pile end bearing, skin friction and lateral bearing behaviours.

• A representative approximation of the topsides structure to reasonably represent the stiffness boundary condition and load transfer mechanism at the top of the jacket.

All phases of the jacket structure should be considered with appropriate levels of appurtenances accounted for, in line with the phases outlined in section 2.2.

Jacket member design shall account for the following, where appropriate;

• Hydrostatic collapse

• Vortex shedding analysis

• Wave slamming analysis

The inplace analyses shall also consider the future allowances as an additional set of load conditions, to those representing the known configuration. Member and joint utilisations shall be reported separately for both these cases.

5.5.2 Redundancy The jacket must be shown to be capable of tolerating the removal of any single bracing member and then withstanding a 10 year return storm without the onset of progressive collapse. Accidental condition load factors shall be adopted for this condition.

5.5.3 Pushover Analysis The purpose of this analysis is to document the jacket Reserve Strength Ratio (RSR) in the intact condition with respect to the 100 year return environmental conditions.

5.5.4 On-Bottom Stability The purpose of on-bottom stability analysis is to ensure sufficient stability, with regards to overturning, bearing and sliding, during jacket installation prior to the driving of the piles. Account shall be taken of the



unpiled and pile stabbed conditions. On-bottom stability condition will be verified using the 1 year (monthly) return environmental conditions for the 3 months centred on the installation period.

Factors of safety on sliding and bearing as per API-LRFD shall be satisfied. Overturning factor of safety of 1.2 shall be satisfied

The analysis shall investigate;

• Establish the maximum mudmat bearing load when the jacket is supported by the mudmats and loaded by the environmental design conditions. The mudmat bearing load will be used for strength checks of the soil capacity to resist bearing and sliding

• Confirm that the jacket, without any piles stabbed, is stable against overturning and sliding when loaded by the 1 year return seasonal wave.

• Establish the maximum wave height that the jacket can sustain when the supports are modelled as springs to reflect the soil conditions at the mudmat locations

• Establish the limiting wave for overturning and sliding after all 4 piles have been stabbed prior to driving.

When developing stability parameters, the forces due to adhesion or negative pressures of the mudmat on the soil shall be ignored.

5.6 FOUNDATION ANALYSIS Foundation design shall be undertaken in undertaken in accordance with the requirements of Total Specification GS EP STR 431 - “Installation of piles for offshore steel structures – driven piles”.

5.6.1 Temporary Foundations The contractor shall demonstrate that the jacket is safe prior to and after the jacket piles have been stabbed, prior to the piles being driven and grouted to the structure.

Temporary foundations in the form of mudmats shall be incorporated in the design, located so as to avoid depressions in the seabed caused by the spud cans of the drilling jack-up platform during previous mobilisations.

A metastable condition shall be defined in which a wave height and period is specified in conjunction with a righting moment due to the selfweight of the structure.

Settlement shall be minimised.

5.6.2 Permanent Foundations The tubular piled permanent foundations of the jacket shall be shown to be capable of being driven to a depth sufficient to develop an adequate capacity to resist the maximum axial bearing and pullout loads with an appropriate factor of safety, whilst the maximum combined pile head load can be safely transferred into the jacket structure.

In making these assessments, due account shall be taken of the proximity effects of the jack-up spud can soil pressure and the possibility of washing out the sand layer when drilling the tophole sections of the wells.

Consideration shall be made of the following design aspects in relation to the foundation design;

• In-Place Pile Analysis

• Ultimate Pile Axial Capacity

• Pile Installation Capacity

• Ship Impact

• Pile Fatigue

• Seismic

• Soil behaviour under cyclical loading



5.7 DYNAMIC & FATIGUE ANALYSIS The natural periods of the complete structure shall be calculated for all phases of the jacket operation, ensuring the range of topside masses are taken into account.

Fatigue lives on the jacket shall be established using a Spectral Fatigue Analysis. A representative linear elastic stiffness representation of the foundation shall be utilised. All cast or welded nodes, joints, splices and connections within the jacket and piles must be capable of manufacturing using established techniques and then shown to be resistant to fatigue induced failures.

Consideration shall be made of the following information in relation to the fatigue analysis;

• Platform Dynamics

• Damage Parameters

• Fatigue Lives

The future topside weight shall be considered in the fatigue analysis. The environmental loading associate with the future riser and j-tube caissons shall not be considered. Sensitivities to fatigue damage with adoption of lower operational topside mass shall be understood and accounted for if more onerous.

For the purposes of global fatigue analysis the corrosion allowances of section 3.3.5 shall be halved.

5.8 SEISMIC ANALYSIS The jacket and foundations must be shown to be capable of safely resisting seismic forces as follows;

• 100 year return period event showing that the API-RP2A LRFD strength level criteria is met

• 10,000 year return period event showing that progressive collapse does not occur

The seismic response spectrum is given in Figure 5-1.



Figure 5-1: Seismic Response Spectrum



5.9 SHIP IMPACT It shall be shown that progressive collapse of the jacket and topside does not occur when a vessel collides with the most heavily loaded leg. Bracing members shall be positioned to prevent a supply boat passing through the face of the jacket. They can be sized such that in the event of a collision they are no longer capable of resisting in-place loads or a second impact.

The vertical extent of the ship impact zone is defined with reference to the maximum environmental conditions in which the platform crane can operate and during which a supply boat can approach the platform. This is defined as between LAT-9.6m and LAT +10.4m.

The jacket shall be designed to absorb the effects of a 5000 tonne supply boat with impact speed of 2 m/s.

Total Kinetic Energy;

• E = ½ amV2, where

o a = 1.4 for broadside impact, and 1.1 for stern impact

o m = Mass

o V = velocity

• E = 14 MJ broadside collision

• E = 11 MJ stern collision

Energy Absorbed by the Structure

• The jackets will be designed to take 4 MJ of the total collision energy, which is consistent with the above vessel displacement of 5000 tonne and impact velocity of 2 m/s.

Irrespective of the possible ship impact directions, all legs in the ship impact zone should be the same size. Similarly all braces in the ship impact zone should be the same size.

It should be noted that the jacket is not required to be designed for ship impact during the phase prior to topside installation.

5.10 FABRICATION AND LOAD-OUT The jacket shall be designed to withstand the loads encountered during all the phases of the fabrication and load-out. In so far as the forces applied to the elements of the jacket during fabrication are dependent on the build method, unless the jacket design dictates an extraordinary method of construction which would require special consideration at the conceptual stage, the Contractor can defer consideration of fabrication loads.

The base case loadout method for the jacket may be by multi-wheeled modular trailers. The analysis boundary conditions for this condition shall be determined by the operating characteristics of these vehicles and shall account for all possible errors, and emergency conditions. This will include an allowance for differential support elevations and emergency stop conditions. A similar approach shall be adopted should a skid beam load-out be adopted

Analysis shall comply with Total Specification GS EP STR 401, “Loadout, seafastening, transportation and installation of offshore structures”

5.11 JACKET TRANSPORTATION ANALYSIS The jacket shall be designed to withstand the loads encountered during transportation from the fabrication yard to the West Franklin site. The analysis shall take account of the sea-keeping characteristics of the nominated transportation barge and cargo. Environmental conditions to be considered shall not be less severe than the 10 year return storm appropriate to the towing route, the time of year and the likely exposure period.

If the Contractor’s sea-fastening scheme could result in force redistribution into the jacket from the flexure of the barge, such effects shall be added to the inertial and gravity forces generated by the barge motion.

Fatigue damage to the primary jacket joints need only be considered for tows in excess of 10 days duration. This is an accumulative duration if transportation is made in more than one voyage.



Analysis shall comply with Total Specification GS EP STR 401, “Loadout, seafastening, transportation and installation of offshore structures”

5.12 JACKET UPENDING AND INSTALLATION ANALYSIS The jacket shall be designed to be installed by a heavy lift vessel and to withstand the loads encountered during the installation. Stages to be considered in the design are as follows;

• Hooking-up the lifting slings, cutting sea-fastening and separating the jacket from the barge,

• Rotating the jacket from the horizontal to the vertical, placing the jacket on the seabed and disengaging the lifting slings,

• Stabbing, driving and grouting the piles,

• Removing all extraneous temporary works and trimming the jacket to level and elevation

The Contractor shall be responsible for all the permanent and temporary components necessary to carry out these operations and for ensuring that they can withstand the full spectrum of applied loadings. The minimum amount of structure should be left on the as-installed jacket that is required for temporary phases of the jacket. That which does remain should not obscure in-service inspections of primary nodes and should be fully accounted for in both static and fatigue analyses.

It is recognised that the installation criteria of the heavy lift contractor will also require to be met.

Analysis and design of relevant components (lift points, transportation supports, etc) shall comply with Total Specification GS EP STR 401, “Loadout, seafastening, transportation and installation of offshore structures”

5.13 APPURTENANCE ANALYSIS & DESIGN A full detail design will be carried out for all prefitted caissons and j-tubes and related supports as outlined in section 4.4. For future appurtenances, the extent of design and supply is limited to the appurtenance supports only.

All phases of the jacket operating sequence shall be recognised in the analysis. Appurtenances and supports shall be designed for all foreseeable loading conditions. These shall include but are not limited to the following;

• Inplace

• Fatigue

• Seismic

• Transportation

• Lift & Upending

• Installation

Specific issues that should be recognised in design include:

• Vortex shedding in Air

• Vortex shedding in Seawater

• Dynamic amplification of cantilevered sections during transportation

• Wave Slamming during immersion of the jacket structure and inplace

It shall be ensured through limiting of the D/t ratio of the appurtenances that secondary bending does not cause local fretting issues at the guides.

5.14 DECOMMISIONING ANALYSIS For decommissioning purposes, an informative case of on-bottom jacket stability shall be done with;

• marine growth,

• full compliment of appurtenances,



• 1 year return summer season environmental condition,

• assumed pile cutting 5m below the mudline.



6 PRODUCTION RISERS

6.1 GENERAL The production risers will be attached to the jacket structure in the jacket fabrication yard and securely held in position for all load conditions of the jacket life including load-out, transportation and installation and for the duration of the jacket design life.

Two risers are to be designed, supplied and pre-fitted at locations indicated in Figure 4-3. Risers have been located inside of the jacket perimeter, and away from the predominant marine operation face, to minimise the risk of damage due to ship impact.

Provision is to be made for future development (further riser(s) housed in a caisson) and, while the weight and environmental forces are considered in the design of the jacket, no design work of future risers shall be undertaken.

6.2 RISER AND SUPPORTS CONFIGURATION

6.2.1 Nominal Size The 2 no. risers shall be 12” in diameter. [HOLD No. 19]

6.2.2 Configuration Riser location in plan on the jacket is indicated in Figure 4-3.

The height of the bottom of the riser above the mudline shall be determined based on the following:

• Riser expansion due to temperature and pressure effects

• Configuration of the tie-in spool at the base of the riser which would be optimised (by others) for ease of installation and limiting stress levels to Design Code requirements,

• Short term jacket settlement, prior to jacket piling while supported by the mudmat, shall be considered so that clearance from the seabed for tie-in operations will require no local dredging for access.

The height of the upper end of the riser shall be determined by the following:

• The top of the riser shall be as high as possible above L.A.T.

• Riser pipe stick-up above the DWS shall not cause stress levels in the pipe greater than those allowed in the Design Code

• Access for future construction of the topsides pipework tie-in is made as simple as possible.

The riser design and analysis shall take account of the probable seabed tie-in spool configuration, the boundary condition being defined by soil elasticity and friction values evaluated from soils data. Similarly a reasonable assumption for the configuration of tie-in pipework at the topsides shall be made for the analysis of the riser pipe. This applies to all the applicable stages of the platform life. All design assumptions and limit states are to be clearly identified and detailed in the design reports.

The upper interfaces shall be by welded connection. A welded cap shall be provided at the upper end of the riser to prevent water flow to/from the inside of the riser pipes. The cap shall be provided with two double block and bleed valves to allow simultaneous flooding and venting of the riser, from the topsides, after installation.

A flange and blind is to be provided at the base of the riser for tie-in of the pipeline. The flange shall be fitted with two double block and bleed facilities to allow venting and flooding of the riser prior to removal of the blind flange. The configuration of the flange termination at the base of the riser shall provide sufficient space to permit the option of flange removal and pipeline spool tie-in by hyperbaric welding.

The risers shall be purged and filled using nitrogen gas prior to jacket load out. This will be to 10 bar pressure



6.2.3 Supports Risers shall be provided with a permanent deadweight support (DWS) near the top of the jacket. Guide supports shall be positioned at intervals along its length with due consideration of strength and VIV considerations in accordance with Design Code requirements.

The DWS shall be located at an elevation that will allow future inspection and thus will be as high on the jacket as possible and in no event lower than 6m above LAT.

The DWS shall comprise a forged, in-line fitting resembling a made up flange set. The internal diameter of the fitting shall be the same as the bore of the riser pipe. The fitting shall be securely, and rigidly attached by bolted connection to the jacket steelwork. Consideration shall be given to the dissimilar materials of the riser and the jacket members.

The riser guides shall comprise a guide barrel with a tubular stub which is then welded to a jacket member. The internal surface of the barrel shall be lined using 27mm thick ribbed polychloroprene (neoprene). The guide shall be designed to provide lateral restraint only to the riser allowing free axial and rotational movement within the guide.

The riser shall be provided with sufficient protection in areas where relative movements between the riser and support steelwork is possible to prevent wear. Such protection shall exist over the entire design life.

6.3 MATERIALS The riser and all fittings shall be manufactured from materials capable of resisting corrosion and environmental cracking in the prescribed environment, see section 6.6, e.g. 25Cr super duplex or Incoloy 825 lined/clad carbon steel for the internal conditions.

The material strength degradation with elevated temperatures shall be taken into account. Such effects shall be the worst of the data provided in DNV OS F101 or material manufacturer’s recommendations.

If superduplex stainless steel is selected, material for the riser pipes shall be supplied in accordance with the requirements of Total Specification GS-EP-PLR-242 “Fabrication of Duplex and Super Duplex Stainless Steel in Seamless Pipes for Pipelines”. The design shall also address Hydrogen Induced Stress Cracking (HISC) issues in accordance with the latest edition of DNV RP F112.

6.4 CORROSION PROTECTION The exterior of the riser shall be protected from external corrosion and environmental cracking in the atmospheric, splash and submerged zones by the use of high integrity coatings and sacrificial anode cathodic protection in accordance with GS EP COR 350 and 100 respectively.

Given the high design temperature of the risers, consideration shall be given to the use of an insulated pipe-in-pipe design to isolate the riser/coating from the external environment and reduce the demands on coating and cathodic protection systems employed. During the design stage, reference shall be made to the detail of the riser designs for the existing Elgin and Franklin interfield pipeline.

6.5 ANALYSIS AND DESIGN

6.5.1 General The riser pipe shall be designed in accordance with the requirements of GS-PLR-100 and DNV OS F101.

The analysis model shall consider the following requirements:

• Consideration of the riser configuration and loading at various phases of its life; from load-out to installation, operation and decommissioning.

• An assumed interaction with the seabed tie-in spool. A rational, assumed seabed tie-in spool configuration shall be adopted. The extent of the assumed seabed pipework shall be such that it’s primary effects on the riser are representative of the probable actual configuration. The resulting loads at the tie-in flange, if applicable, shall be highlighted in the design report summary with an indication of the level of flange utilisation.

• Soil stiffness.

• Riser support stiffness, including the true behaviour of the DWS on it’s support steelwork.



• An assumed interaction with topsides tie-in pipework. The extent of the assumed pipework shall be such that it’s primary effects on the riser are representative of the probable actual configuration. The resulting loads at the tie-in shall be highlighted in the design report summary with an indication of the level of utilisation.

• The effects on the seabed pipe, and hence on the bottom of the riser, due to measures taken (by others) for dropped object protection.

• Accidental loading on any horizontal section of the riser by dropped objects. The assumptions made in respect of (assumed) tie-in spool touch down on the seabed shall be taken into consideration and explicitly reported in the design report.

6.5.2 In-service Load Conditions For in-service, operational conditions the riser analysis model shall be subject to loads, including, but not limited to:

• Gravity loads.

• Temperature and pressure effects.

• Extreme condition wave and current for both maximum and minimum still water depths. Wave directionality shall be considered.

• Jacket displacements.

• Loads emanating from tie-in pipes (seabed and topsides).

• Slugging effects (if any) from transported fluids.

Loads shall be combined to form representative load conditions as required by the Design Code.

6.5.3 Fatigue Conditions For fatigue analysis the riser analysis model shall be subject to loads causing varying stress levels over the design life of the platform, including, but not limited to:

• Hydrodynamic forces due to waves and currents, combined effects shall be generated. Wave directionality and wave phasing shall be considered to ensure that representative stress ranges are evaluated at critical locations both in terms of position on the riser and positions around the riser circumference.

• Jacket displacements due to the effects of a passing wave (and current) shall be considered.

• Effects of operating cycles; variations in temperature and pressure

• Effects of sea transportation

• The effects of vortex induced vibrations (VIV), although limited VIV shall only be permitted in extenuating circumstances and riser support conditions shall be arranged to prevent the onset and proliferation of VIV.

• The effects of riser strength and leak tests

• An assessment of the effects of vibration and noise created by fluid flow to ensure that small bore piping connected to the riser is not effected (if applicable).

6.6 DESIGN BASIS DATA

6.6.1 Design Life The design life of the risers shall be 35 years

6.6.2 Temperature and Pressure The operating pressure and temperature at the riser inlet varies through the design life as follows:

• Early life (to end 2013) : 80 bara 1570C

• Mid life (to mid 2017) : 56 bara 151.60C



• Late life (to end 2046) : 31 bara 124.90C

The design temperature shall be 1900C

The design pressure shall be 250 barg

6.6.3 Fluid Composition The fluid composition is as follows:

Mole % Mole % N2 0.418 C6 1.428

CO2 2.556 C7 1.743 C1 73.759 C8 1.253 C2 7.721 C9 0.726 C3 4.041 C10 0.681 iC4 1.052 CN1 1.298 nC4 1.507 CN2 0.287 iC5 0.801 CN3 0.080 nC5 0.649

Table 6-1: Fluid Composition

The concentration of H2S shall be taken as 60 ppm.

Water Composition (mg/l)

Na+ K+ Ca2+ Mg2+ Ba2+ Sr2+ Fe2+ Cl- SO42- HCO3

-

80520 8000 20000 2500 3700 2000 560 173700 7 180

Table 6-2: Water Composition

6.6.4 Flow Rates The following flow rates for the constituent parts shall be adopted:

Gas Liquid Gas Liquid

ksm3/d sm3/d kg/hr kg/hr

Early - Nov 2013 8507 2340 378,400 75,460 Mid - June 2017 3260 931 141,600 31,583 Late - Oct. 2046 163.9 61.6 6,916 2,120

Table 6-3: Flow Rates

No liquid slugging is expected.

6.6.5 Operating Cycles Operating cycles shall be defined based on the following information:

• Worst case temperature changes are on start-up from cold wells and will be approximately as follows:

• Temperatures in the range -40 to -10°C for 30 minutes (at very low rate)

• Temperatures in the range -10 to +5°C for 30 minutes

• Temperature rising from +5 to +70°C for 30 minutes

• Ramp up to full production rates & normal operating temperature over 30 minutes to one hour.

• Pressure for this case will range from 10barg (for the first 90 minutes) to normal operating pressure.

• The pressure will drop when the pipeline is shut-in as it cools (from 80 barg inlet life at 157°C to 35barg when the line has cooled to 4degC).



If the line is shut-in for an extended period, it will be blowdown to approximately 10barg.



7 WELLHEAD ACCESS DECK PERFORMANCE CRITERIA

7.1 FUNCTION The Wellhead Access Deck (WAD) is required to provide access during the installation phase and for well access during the jack-up phase prior to topside installation. It is envisaged that it will provide well access for a period of up to a maximum of 3 years when it shall be removed by a heavy lift vessel, prior to it installing the permanent topsides. The WAD shall be attached to the jacket structure in the fabrication yard.

7.1.1 Installation Phase During the jacket installation phase, the WAD may be utilised by the installation contractor for sling laydown, cutting and welding equipment laydown and provide main access between the jacket and HLV via a gangway system. The WAD will be cleared, except for a navigation aid package and gangway support structure prior to the jacket installation HLV departing the field. To comply with HLV requirements the deck will have all slots for the completed wells filled in, i.e. a continuous deck shall be provided.

7.1.2 Jack-Up Phase During the jack-up phase, the jack-up will be stationed on the platform south face and shall be capable of accessing all 12 conductor slots. It is envisaged that only 3 wells are completed during this phase but allowance shall be made to a maximum of 5. The position for these wells cannot be defined prior to ITT award therefore all 12 conductor slots shall be capable of being accessed.

Prior to installing a conductor to a particular well slot, the jack-up drilling contractor shall require that all structure in the vicinity to be removed sufficiently to run components, with clearance, through the WAD, the widest of which shall be the 48” (1219mm) centraliser intended for the in-air guide. A 1400mm diameter clear opening shall be provided centred on each “as-designed” conductor centre.

Steelwork shall be provided to chock each conductor securely to the WAD framework after drilling is completed and there is no connection between the jack-up rig and the conductor. This steelwork shall take account of the possible position deviation of the conductor, from “as-designed”, in the opening and shall be designed to be readily handled and fixed manually.

7.1.3 WAD Removal Prior to installation of the topside deck structure, the topside installation contractor will remove the WAD. Two docking pins will be installed to the tops of the jacket legs, their purpose to provide guidance for WAD removal and subsequent topsides installation, preventing impacting on the installed wellheads. The WAD will incorporate guide barrels to wrap around the docking pins, the dimensions of which shall assure no snagging but tight enough to avoid touching the wellheads.

During WAD removal the clear opening diameter around each conductor shall be 2200mm. The steelwork panels developing this opening shall be readily removed and handled manually. See Figure 7-1.

The docking pins shall be supplied and installed by others. The design of the top of the jacket legs for fitting and fixing of the docking pins shall be the responsibility of the jacket CONTRACTOR. The design loads for the support of the docking pins shall be developed from the heavier topsides weight, see section 8.



Figure 7-1: Example of WAD structure Prior to Deck Removal

7.2 LAYOUT The platform shall be supported off the jacket structure. Framing of the structure shall consider the wellhead locations and the amount steelwork removal required to provide clearances for conductor completion and WAD removal.

The target elevation of the WAD top of grating would ideally be identical to the as-installed permanent deck lower deck to aid drilling activities. As the actual level of jacket settlement is unknown at the time of setting the WAD elevation, the minimum expected level of jacket settlement shall be accounted for.

Gangway landing supports shall be pre-installed on the platform for immediate access after the installation of the jacket. [HOLD No. 5]. Access from the WAD to the four legs shall be provided via stairs. Scaffold starters shall be provided on the access platform around the legs where pre-installing of walkways would clash with lift rigging.

The temporary deck structure shall be pre-installed in the fabrication yard and transported to West Franklin with the jacket. Temporary seafastening for the deck shall be provided and subsequently be removed after installation.

Padeyes shall be provided for the removal of the platform. The padeyes shall be located so that lift rigging can be readily and safely attached. The platform shall be designed such that the whole deck can be removed as an entire unit including the walkways around the legs. The lift rigging will utilise either a spreader bar or a lifting frame as appropriate so that it avoids contact with the installed wellheads. For clarity, it shall be assumed that all wellheads will be in place although, if better information is available, the actual position of wellheads will be provided.

7.3 FORM OF ATTACHMENT TO JACKET The WAD shall be attached to the jacket structure during the jack-up phase with the minimum number of interfaces and fixing connectors sufficient to maintain integrity during all foreseeable environmental loading. It is envisaged that additional seafastening attachments may be required in order that the structure is adequately supported during jacket loadout, sea transportation, and installation lift.



The support method shall be such that in the removal of fixing connectors prior to the removal lift, the structure remains stable and is adequately supported for this temporary condition. Removal of the connectors shall be in a location readily accessible and weight of any components will be minimised to aid manual handling.

7.4 BASIS OF DESIGN The Wellhead Access Platform shall be capable of resisting the following design loading;

In-situ

• UDL of 5 kN/m2 over entire plan area

• UDL of 15 kN/m2 locally over deck beams, stringers, grating and removable panels only

• Bridge Landing from the Jack-up Platform. [HOLD No. 5].

• Environmental loading shall be evaluated based on a 100 year return period

Transportation

The structure and its attachment to the jacket shall be capable of resisting the forces generated during transportation.

Jacket Installation Lift

The structure and its attachment to the jacket shall be capable of resisting the forces generated during jacket lift and upending.

7.5 NAVIGATIONAL AIDS During the temporary phase prior to the installation of the permanent topsides it is required adequate navigational aids are provided on the temporary structure. It is envisaged that this shall be provided through a single skid located and secured on the WAD structure.

CONTRACTOR shall supply and install a navigational-aids package complete with fog horns. The package shall consist of a small demountable bracket supporting a main and secondary warning lantern suitable for UK coastal waters, a battery pack with an endurance of 3 months, and a synchronising cable running to the attendant Jack-up. After an estimated period of 3 months, electricity supply will be taken from Jack-up. The Jack-up shall also supply the synchronising unit. The package shall be in accordance with the relevant regulations and requirements of HSE.

As a minimum, the main lantern shall be rated to 15 nautical miles and the secondary lantern to 10 nautical miles. The fog signal shall be certified as a 2 mile signal.



8 TOPSIDE STRUCTURE INTERFACE

8.1 GENERAL

8.1.1 Installation Prior to the installation of the West Franklin Topside Structure onto the jacket structure it is intended that:

• Wellheads will be in place at the top of conductors.

• The tops of the jacket legs will have been cut to define a true horizontal plane at the required stab-in elevation.

• The WAD will have been removed

The wells will terminate within the volume of the final installed position of the topside structure. Docking pins, by others, are provided on 2 of the legs to guide the removal of the WAD and installation of the topsides.

The jacket shall be capable of supporting the installation loads associated with the topside structure. Any leg will be capable of supporting a lateral and vertically guidance load at the uppermost tip of the guide pins. The guidance load shall be taken as acting laterally and vertically downwards concurrently. This combination shall be checked for all compass points.

Lateral Impact: 10% of Topside Installation Weight

Vertical Impact: 10% of Topside Installation Weight

Impact Point +10.5m above Top of Leg cut off

Table 8-1: Topside Installation Pin Design Data

8.1.2 Future Developments As per section 4.4, provision shall be made within the jacket design to guide the future appurtenances, designed by others, should they be required. The design of the jacket shall account for the additional environmental loading at the appropriate stages of design.

A future weight allowance, centred on the geometric centre between the main legs shall be accommodated at the appropriate stage of analysis. Care shall be taken that the inclusion of the future load is the most onerous case for each analysis type.

8.1.3 Sea Escape Ladders Sea escape ladders running from (just below) the deck stab-in elevation to sea level shall be provided. These are essential for the safety of personnel on the platform and must function for the full life of the field. They should therefore be robust, protected from corrosion, and capable of being easily replaced in the event of future damage. Rest platforms shall not be provided.

Their use shall be required in both the temporary phase with the Wellhead Access Deck in place and for linking up to the permanent topside structure.

8.2 TOPSIDE HOOK-UP OVERVIEW

8.2.1 Appurtenance Hook-up This shall be as outlined in section 4.4

8.2.2 Levelling of Topside Stab-in Points Not less than 0.85m “green” material shall be provided at the tops of the jacket legs beyond the “as-designed” interface with the topsides legs. Prior to topside installation, the green material shall be removed, by others, to produce a level support plane at the elevation determined to suit the required air gap.



8.2.3 Temporary Top of Leg Seal In order to prevent ingress of material into the jacket legs it is required that the top of the legs be sealed with a temporary cap following installation of the jacket.

8.3 AIR GAP PROVISIONS

Provision Allowance

Initial penetration of the structure into the seabed

To be determined by CONTRACTOR NOTE 1

Long Term Reservoir Compaction 1.5m

Water Depth Tolerance +/- 1.0m

Long term increase in water levels due to changes in climate

0.3m

Inclination of the structure To be determined by CONTRACTOR

Table 8-2: Air Gap Provisions

Note 1: Short-term mudmat settlement shall be derived from analysis of the soil characteristics supplied in Appendix 3, taking due consideration of TEPUK experience in the Elgin/Franklin field of actual settlement versus predicted.

8.4 TOPSIDE STRUCTURAL INTERFACE

Interface Data

Topside Bottom of Steel The Topside Bottom of Steel (BOS) required to meet the air gap requirements, see section 2.7.2.

Jacket Leg cut-off elevation 0.6m below the Topside BOS

“Green” Material on Jacket Legs Sufficient to meet tilt and mudmat over-settlement requirements (Not less than 0.85m)

Expected Topside Top of Steel 1m above BOS

Leg spacing: 22.5m x 22.5m

Number of legs supporting deck 4 (Four)

Topside Leg diameter/thickness Provisionally 1400 mm diameter; 40mm thick but will match that provided by the jacket

Table 8-3: Topside Interface Data

8.5 OUTLINE TOPSIDES DATA

8.5.1 Topside Mass and Weight Topsides weight and centre of gravity are specified in Table 8-4. In order to correctly predict the natural frequencies the flare mass shall be modelled discretely.



For the purposes of Jacket design a Centre of Gravity (CoG) envelope of +/-0.75m in all directions shall be considered. Northing and Easting are to the Platform North as indicated on Figure 4-2. CoG origin is considered as being at the intersection of Lower deck Top of Steel (TOS) and the Platform SW Leg.

Weight (tonnes) Centre of Gravity Phase

Dry Operating N E Elevation

Deck Installation NOTE 1 2500 - 13.80 13.7 6.4

Deck 2897 3124 13.8 13.7 6.4

Flare 282 282 53.9 11.5 38.1

In-situ NOTE 2

Combined 3179 3406 17.4 13.5 9.2

Deck 4897 5124 12.8 12.7 12.8

Flare 282 282 53.9 11.5 38.1

Future NOTE 2

Combined 5179 5406 15.0 12.7 14.2

Table 8-4: Topside Gross Not-To-Exceed Weight Phase Data NOTE 1: Installation of the topside structure may occur up to 3 years after the jacket structure has

been installed. The minimum topside weight for consideration in jacket analysis is therefore zero.

NOTE 2: Based on conceptual topside design incorporating 20% Weight Growth at 6th Nov 09.

8.5.2 Topside Environmental Loading Topside projected areas to be considered for wind loading are presented in Table 8-5. For the purposes of flare wind loading a solidity ratio of 0.25 shall be considered. Northing, Easting and origin are as per section 8.5.1.

Area Offset from SW Leg @ Lower Deck TOS

(m2) Northing

(m)

Easting

(m)

Elevation (m)

Topside 645 - 16.3 8.3 Platform North and South Face Flare Boom 1100 - 11.25 30.7

Topside 565 15.0 - 8.0 Platform East and West Face Flare Boom 500 50.0 - 31.8

Table 8-5: Topside Environmental Parameters



9 SUBSEA DRILLING TEMPLATE INTERFACE

9.1 FUNCTION A subsea drilling template, designed and installed by others, shall provide guidance to align the predrilled wells with the jacket conductor spacing. This guidance will be provided via 2 no. docking piles, which will be installed and surveyed by others, located off the subsea drilling template which shall correspond to locating receptacles on the jacket structure.

The receptacles on the jacket shall therefore locate and orientate the jacket in plan relative to the wells.

9.2 LAYOUT At the time of jacket installation the docking piles will be structurally isolated from the drilling template.

The locations of the docking piles shall be as to suit that of the receptacle layout of Figure 9-1

9.3 DOCKING PILES DATA Two docking piles shall be present at the nominated site, having been installed through the pile sleeves attached to the drilling template structure by others. Following installation of the docking piles, the sleeves will be detached and removed from the body of the template in order to insulate the pre-drilled wells from the jacket docking forces.

The magnitude of the forces developed during docking shall be estimated from considerations of the geometry and mass of the jacket, and the method of installation. Until further information is available, the following docking pile design criteria shall be adopted;

• Stick-up of installed docking pile above mudline:

o 1st Engagement at +8.0m

o 2nd Engagement at +6.5m

• Laterally applied docking force of 1750 kN on receptacle applied in any direction

• Vertically applied docking force of 400 kN on receptacle

• Docking Pile Outer Diameter at 914mm (36”) [HOLD No. 8] throughout its length

• Target at rest elevation of bottom of receptacle shall be 1.5m above mudline, however due consideration shall be given to uncertainties in jacket settlement on the mudmats

9.4 DOCKING PILE RECEPTACLES Indexing receptacles for locating the jacket on the template docking piles shall be provided in the lowest plan bracing elevation of the jacket structure.

9.4.1 Corrosion Protection For the purposes of corrosion protection it can be assumed that there is no continuity between the jacket structure and the docking pile. Once the jacket is installed the docking pile has no further function.

9.4.2 Fabrication and Tolerances To ensure that the wells drilled through the template can be tied back to the topside wellheads it is important that the stack-up of fabrication and installation tolerances in the template, docking piles, and the jacket is not so excessive as to prejudice this operation.

Jacket Fabrication

The jacket fabricator shall ensure that the positional tolerances of the 2 docking receptacles are within fabrication tolerances. Specifically with regards to the relative horizontal distance between the two points and alignment of the vertical plane which these points define relative to its theoretical position.

This is to ensure alignment with docking pin location for jacket installation and to ensure that in the set down that the jacket conductor slots are aligned with the predrilled wells guided off the template.



Docking Pile Tolerance

A dimensional survey will be undertaken by the template fabricator in the fabrication facility to determine all dimensions between template guide centres and docking pile guide centres.

The template installer will contract the services of specialist subsea metrology service provider. The following dimensions will be provided:

• horizontal dimensions between docking piles at mudline

• verticality of the docking piles

• geographical orientation of the docking piles

• horizontal dimensions between docking piles and well slot centres on the template

This information shall be adopted to determine docking pile receptacle layout and locations and assure the relative positions of conductor guide centres for design.



Figure 9-1: Docking Pile Plan Receptacle Location – Ref WFA-JAC-00-S-GA-10023-001 (Appendix 2)



10 JACK-UP DRILLING PLATFORM INTERFACE

10.1 NOMINATED RIG For the purposes of design the nominated drilling shall be taken as the Rowan Gorilla V. See Appendix 4: Jack-Up Platform Data.

10.2 CONDUCTOR SLOT ACCESS A total of 12 wells must all be accessible from the nominated drilling jack-up platform founded adjacent to the jacket such that its transom clears the jacket centreline horizontally by at least 5.0m.

The placing accuracy of the Jack-Up Platform must be considered when estimating clearance and influences. For the nominated jack-up platforms, see Appendix 4: Jack-Up Platform Data, these are +/-0.5m for the offset and stand-off, and +/-3 degree orientation (all concurrent).

The proposed conductor slot arrangement consists of a 2-2-3-3-2 arrangement, see Figure 4-3, working away from jack-up face with a nominal 3.0m spacing between conductor centres. The initial location of the jack-up is proposed to be the North Face to minimise soil disturbance. Once the jacket is installed the jack-up shall then set up on the South Face for all remaining activity. The CONTRACTOR shall ensure all conductor slots are accessible for the nominated rig while allowing for the above tolerances on position.

Minimum Jack-Up capacity at all slot locations to be achieved is 1000 (metric) tonnes.

10.3 CONDUCTOR SLOT DESIGN The maximum allowable vertical span between conductor guides is limited to 30m. The conductor slots shall be taken as 42” ID subsea. The in-air conductor slot shall be 48” ID.

The guide funnel, above and below the slot, and adjacent bracing structure must resist gravity forces from a misaligned conductor pipe. The magnitude of this force can be taken as 200 kN applied vertically on the top edge of the cone.

10.4 JACK-UP LOADING Due to relative displacements of the jack-up platform and the jacket, the transfer of forces between the jack-up and the jacket prior to the deck installation shall be represented by a 500 kN horizontal load applied in any direction to any one conductor at its upper end and reacted at the conductor guides in the jacket.

The high level platform for man access to the wellheads will not be required to resist the loads as any chocking of the conductors shall only take place after the jack up drilling rig has finished work over that slot.

10.5 FOUNDATION LOADING Interface of the Jack-up platform spud can foundations on the platform piles shall be assessed to ensure acceptability.

Due account shall be made of the following;

• Proximity of spud cans to jacket piles and effect of bearing pressures from spudcan on capacity of piles

• Proximity of disturbed soil left by Jack-Up Platform spudcans to mudmats following the initial drilling over the subsea template and the effects on mudmat / soil capacity, see Figure 10-1.

Details of the proposed jack-up platform are contained in Appendix 4: Jack-Up Platform Data. Spud can reactions shall be considered as per Table 10-1.



SPUD CAN CONDITION REACTION

(Klbs)

Pre-Load 34,400

Stillwater 18.900

Table 10-1: RGV Jack-Up Platform Spud Can Reactions


Doc No. WFA-S-SP-1000 Rev A2 Page 56

Figure 10-1: Proposed Initial Jack Up Platform Location (North Face) - prior to Jacket Structure Installation



11 WEST FRANKLIN JACKET STRUCTURE PROPOSED OUTLINE CONCEPT

11.1 OUTLINE In order to expedite the installation of the West Franklin Jacket structure as soon as practicable, TEPUK propose the use of the framing arrangement as detailed in APPENDIX 2: Proposed Jacket Structure Outline Concept Drawings and provided in Reference 4.

At the request of TEPUK, Aker Solutions have developed the jacket utilising proven framing, appurtenance layout and support details on the existing Elgin and Franklin Wellhead structures. The framing developed has progressed on;

• The experience gained in-service of the Elgin and Franklin Wellhead structures,

• Knowledge and experience of adopting the original design reports,

• Knowledge of the existing integrity models

• New structural analysis reflecting the design data within this specification.

The new analysis carried out to date that is captured in the drawings reflects the revised inplace configuration.

11.2 MAJOR DEVIATIONS FROM EXISTING WHP STRUCTURES The following points highlight the significant deviations from the existing structures

• Site specific water depth – To be confirmed by CLIENT, see references 6 and 7.

• Site Specific Soil Characteristics – To be confirmed by CLIENT, see reference 6.

• Indexed interface with Subsea Docking Piles located off Subsea Drilling Template.

• Conductor, Caisson, J-tube and riser requirements

• Topside Weight and Centre of Gravity (COG), affecting both the static load distribution, and the Dynamic Amplification Factors (DAF) to apply.

• Meeting up to date Metocean Air Gap Requirements. This is not reflected in drawings. As outlined in section 2.7.2, this is to be set by CONTRACTOR.



11.3 WEIGHT REPORT The following weight summary is based on the as-modelled West Franklin jacket template and known tertiary weights from the original wellhead structures. A design contingency has been applied in line with Total Specification, GS EP STR 001, “Weight monitoring and weighing offshore units”. A more detailed breakdown is contained in Appendix 3.

These are only to be considered as indicative weight of the proposed template structure.

Condition Not To Exceed Gross Weight

(Tonnes)

Temporary Inplace 3673

Operating Inplace 3524

Transportation 4129

Lift 3330

Table 11-1: Template Weight Summary



12 EXISTING ELGIN / FRANKLIN WELLHEAD STRUCTURES

The following section outlines the existing TEPUK wellhead structures within the Elgin/Franklin Field. These are in similar water depths and, apart from a proposed flare on West Franklin, have similar topside layouts.

12.1 FRANKLIN WHP GENERAL DESCRIPTION Franklin Wellhead ‘A’ jacket was installed in 1997 complete with a temporary drilling access platform in place. This was removed over the completed wellheads prior to the topsides installation.

The following points regarding the design are highlighted regarding Franklin Wellhead ‘A’ and its applicability to use for the West Franklin Jacket;

• Franklin Jacket incorporates several cast nodes on main joints

• Franklin Jacket incorporates some braces which are flooded by design

• Revised metocean data will require the West Franklin topside structure to be raised from the Franklin Wellhead ‘A’ level

• Site specific water depth may affect the bracing angles of the structure

• Local soil conditions may affect mudmat and pile size with knock-on implications for incoming bracing.

12.2 ELGIN WHP GENERAL DESCRIPTIONS Elgin Wellhead ‘A’ jacket was installed in 1997 complete with a temporary drilling access platform in place.

In addition to section 12.1, the following point is highlighted;

• Jacket was located on subsea docking piles which had been located off the subsea drilling template. This modified the mudline elevation relative to the Franklin jacket.

12.3 IMPROVEMENTS IN DESIGN REQUIRED Should the existing TEPUK structures be utilised in forming the basis of the West Franklin structures then the following points should be addressed.

12.3.1 Fatigue lives on Hot Nodes Fatigue design of the jacket shall ensure that the jacket structure is compliant with section 5.7 with regards to fatigue lives being met without weld profiling being carried out.

12.3.2 Flooded Member Detection All brace members shall be non-flooded to enable the use of Flooded Member Detection Inspection as a method of detecting through thickness cracks

12.4 LESSONS LEARNT As part of the close out of the original Elgin / Franklin EPIC contract, the following statement was recorded;

• The designers concluded that a slight reduction of the angle of incidence for the pile sleeve bracing to the leg would have considerably enhanced its fatigue performance.



12.5 FRANKLIN WHP FACTSHEET

FRANKLIN WELLHEAD PLATFORM ‘A’

Jacket Topside

Jacket Installed Weight 2800 tonnes Current Topside Operating Weight 2200 tonnes

Jacket Installation Date 1997 Topside Installation Date 1999

Structural Form Lift installed, 4 legged wellhead jacket structure with zero batter on faces and 45 degree rotated base. 22.5m x 22.5m at topside interface and 31.8m x 31.8m at rotated base. Internal conductor guides supporting 9 no. conductors provided off plan diamond bracing which in turn frames off the intersection of the elevation diamonds at cast node joints. No subsea drilling

Foundations 4 no. single 2590mm diameter (75mm wt) piles, driven to a soil depth of 56m through a grouted sleeve. On bottom stability was provided by 4 no. 7.8m diameter circular mudmats at the base of the grouted sleeves.

Appurtenances Jacket Installed with:

• Guides for 9 no. Conductors, 42” ID Subsea, 48” in-air

• 6” Sewage Caisson in final position

• 20” Seawater Caisson recessed vertically within jacket, pulled up following topside installation

• 4 no. J-tubes

Retrofitted prior to topside installation:

• 42” Riser Cooling Caisson. Installed as single item, c.180 tonnes, dead weight carried at +12m, with caisson terminating at +17m and -85m.

Appurtenances 3 no. 38” Caissons

or

2 no 38” Caissons with 2 no. 12” risers

Future Design Capacity

Topsides 2000 tonne Drilling Workover Unit

Corrosion Protection Painted with Anode Protection

Table 12-1: Franklin 'A' Factsheet



Figure 12-1: Franklin 'A' Jacket Structure Perspective with Wellhead Access Deck



Figure 12-2: Elgin 'A' Jacket Structure Perspective with Wellhead Access Deck


Doc No. WFA-S-SP-1000 Appendices

APPENDICES



APPENDIX 1: FIELD LAYOUT



Figure I: Elgin Franklin Field Layout



Figure II: Existing Field Layout



APPENDIX 2: PROPOSED JACKET STRUCTURE OUTLINE CONCEPT DRAWINGS

The following drawings are available in Reference 4.



Document Title Drawing Number

West Franklin Phase II

Wellhead Platform ‘A’ Jacket

WFA-JAC-00-S-GA-10029-001 GENERAL NOTES

WFA-JAC-00-S-GA-10000-001 ISOMETRIC VIEW

WFA-JAC-00-S-GA-10001-001 ELEVATIONS ON GRID LINES ‘A’ & ‘B’

WFA-JAC-00-S-GA-10002-001 ELEVATIONS ON GRID LINES ‘1’ & ‘2’

WFA-JAC-00-S-GA-10003-001 ELEVATION ON GRID LINE ‘A’ LOOKING NORTH (EL +21.350 TO -28.000)

WFA-JAC-00-S-GA-10004-001 ELEVATION ON GRID LINE ‘A’ LOOKING NORTH (EL -25.555 TO -68.000)

WFA-JAC-00-S-GA-10005-001 ELEVATION ON GRID LINE ‘A’ LOOKING NORTH (EL -68.000 TO -92.400)

WFA-JAC-00-S-GA-10006-001 ELEVATION ON GRID LINE ‘B’ LOOKING NORTH (EL +21.350 TO -28.000)

WFA-JAC-00-S-GA-10008-001 ELEVATION ON GRID LINE ‘B’ LOOKING NORTH (EL -25.555 TO -68.000)

WFA-JAC-00-S-GA-10007-001 ELEVATION ON GRID LINE ‘B’ LOOKING NORTH (EL -68.000 TO -92.400)

WFA-JAC-00-S-GA-10009-001 ELEVATION ON GRID LINE ‘1’ LOOKING NORTH (EL +21.350 TO -28.000)

WFA-JAC-00-S-GA-10010-001 ELEVATION ON GRID LINE ‘1’ LOOKING NORTH (EL -25.555 TO -68.000)


WFA-JAC-00-S-GA-10012-001 ELEVATION ON GRID LINE ‘2’ LOOKING NORTH (EL +21.350 TO -28.000)



WFA-JAC-00-S-GA-10015-001 BASE FRAME VERTICAL FRAMING ELEVATION ON NORTH WEST FACE

WFA-JAC-00-S-GA-10016-001 BASE FRAME VERTICAL FRAMING ELEVATION ON NORTH EAST FACE

WFA-JAC-00-S-GA-10017-001 BASE FRAME VERTICAL FRAMING ELEVATION ON SOUTH WEST FACE

WFA-JAC-00-S-GA-10018-001 BASE FRAME VERTICAL FRAMING ELEVATION ON SOUTH EAST FACE

WFA-JAC-00-S-GA-10019-001 PLAN ON FRAMING @ +8.000

WFA-JAC-00-S-GA-10020-001 PLAN ON FRAMING @ -18.000




WFA-JAC-00-S-GA-10024-001 CONDUCTOR GUIDES SUPPORTS PLAN @ +8.000

WFA-JAC-00-S-GA-10025-001 CONDUCTOR GUIDES SUPPORTS PLAN @ -18.000



WFA-JAC-00-S-GA-10028-001 ELEVATIONS ON GRIDLINES ‘A’ & ‘B’ SHOWING INTERNAL RING STIFFENING AND DIAPHRAGM PLATES

WFA-JAC-00-S-GA-10030-001 APPURTENANCE DRAWING – GRID LINES A & B

WFA-JAC-00-S-GA-10031-001 APPURTENANCE DRAWING – GRID LINES A & B

WFA-JAC-00-S-GA-10032-001 APPURTENANCE DRAWING – GRID LINES 1 & 2

WFA-JAC-00-S-GA-10033-001 DRILLERS TEMPORARY PLATFORM – GENERAL ARRANGEMENT

WFA-JAC-00-S-GA-10034-001 DRILLERS TEMPORARY PLATFORM – ELEVATIONS

WFA-JAC-00-S-GA-10035-001 DRILLERS TEMPORARY PLATFORM – SECTIONS



APPENDIX 3: PROPOSED JACKET STRUCTURE TEMPLATE WEIGHT REPORT

See section 11.3 for description



Gross Weight

(tonnes)

Group

Nett Weight

(tonnes) Cont.

% Lift Trans Temp. In

Place Operating In-Place

PDMS Modelled Steelwork Framing @ EL+8.000 43.75 15 50.3 50.3 50.3 50.3 Framing @ EL-18.000 37.99 15 43.7 43.7 43.7 43.7 Framing @ EL-38.000 37.99 15 43.7 43.7 43.7 43.7 Framing @ EL-68.000 37.42 15 43.0 43.0 43.0 43.0

Base Frame 711.74 15 818.5 818.5 818.5 818.5

Mud Mats 66.5 50 99.8 99.8 99.8 99.8

Jacket Installation Guide Frame 23.32 15 26.8 26.8 26.8 26.8 Grid Line A 564.42 15 649.1 649.1 649.1 649.1 Grid Line B 566.88 15 651.9 651.9 651.9 651.9 Grid Line 1 141.58 15 162.8 162.8 162.8 162.8 Grid Line 2 139.83 15 160.8 160.8 160.8 160.8 Non-Modelled Steelwork Conductor Guides 46.04 15 52.9 52.9 52.9 52.9 Cast Nodes El. -18.0 23.6 15 27.1 27.1 27.1 27.1 Cast Nodes El. -38.0 23.6 15 27.1 27.1 27.1 27.1

BASIC GROUP 16.2 2857.6 2857.6 2857.6 2857.6 Permanent Ladders 1.38 15 1.6 1.6 1.6 1.6 SW Caisson 25 15 28.8 28.8 28.8 n/a SW Caisson Supports 5 15 5.8 5.8 5.8 5.8 FW Caisson 25 15 28.8 28.8 28.8 n/a FW Caisson Supports 5 15 5.8 5.8 5.8 5.8 Sewage Caisson & Supports 1.89 15 2.2 2.2 2.2 2.2 J-Tubes & Supports 30 15 34.5 34.5 34.5 34.5 Risers & Supports 30 15 34.5 34.5 34.5 34.5 Future Riser Caisson Supports 6.6 15 7.6 7.6 7.6 7.6 Future J-Tube Caisson Supports 21.375 15 24.6 24.6 24.6 24.6 Tugger Bollards 0.163 15 0.2 0.2 0.2 0.2 Tugger Pad Eye 0.022 15 0.0 0.0 0.0 0.0

APPURTENANCES 15.0 174.1 174.1 174.1 116.6 Anodes 115.07 15 132.3 132.3 132.3 132.3 Paint 8.437 15 9.7 9.7 9.7 9.7

PROTECTION 15.0 142.0 142.0 142.0 142.0 Trunnions 13.2 15 15.2 15.2 15.2 15.2 Hubs 7.7 15 8.9 8.9 8.9 8.9 Sling Retainers 3.3 15 3.8 3.8 3.8 3.8 Keeper Plates 1.602 15 1.8 1.8 1.8 1.8 Ring Stiffeners 2.404 15 2.8 2.8 2.8 2.8 Ring Stiffeners 0.971 15 1.1 1.1 1.1 1.1



Gross Weight

(tonnes)

Group

Nett Weight

(tonnes) Cont.

% Lift Trans Temp. In


Padeye 23.793 15 27.4 27.4 27.4 27.4 LIFTING AIDS 15.0 345.0 345.0 345.0 345.0

Grout Lines 1.03 20 1.2 1.2 1.2 1.2 Grout Lines 1.669 20 2.0 2.0 2.0 2.0 Inflation Line 1.489 20 1.8 1.8 1.8 1.8 Inflation Line 0.807 20 1.0 1.0 1.0 1.0 Packers 2.606 15 3.0 3.0 3.0 3.0 Leg Flooding 2.533 15 2.9 2.9 2.9 2.9 Leg Flooding 1.283 15 1.5 1.5 1.5 1.5 ID Marks 0.515 15 0.6 0.6 0.6 0.6

INSTALLATION AIDS 17.1 14.0 14.0 14.0 14.0 Ring Stiffeners 0.935 15 1.1 1.1 1.1 1.1 Support Stools 2.126 15 2.4 2.4 2.4 2.4 Support Stools 2.126 15 2.4 2.4 2.4 2.4

TRANSPORTATION AIDS 15.0 6.0 6.0 6.0 6.0 Docking Pin no. 1 8.826 15 n/a n/a 10.1 10.1 Docking Pin no. 2 9.602 15 n/a n/a 11.0 11.0

DOCKING PINS 15.0 0.0 0.0 21.2 21.2 WAD 80 15 92.0 92.0 92.0 0.0

WELLHEAD ACCESS DECK 15.0 92.0 92.0 113.2 21.2 Slings 160 15 n/a 184.0 n/a n/a Rigging 84 15 n/a 96.6 n/a n/a Sea Fastening 44 15 n/a 50.6 n/a n/a Speeder Bar 120 15 n/a 138.0 n/a n/a Link Plate 25 15 n/a 28.8 n/a n/a

LOADOUT / TRANSPORT 15.0 0.0 498.0 0.0 0.0

Lift Trans Temp. In


SUMMATION 3330.7 4128.7 3673.1 3523.6



APPENDIX 4: JACK-UP PLATFORM DATA

The following Jack-Up Platform data is provided for the Rowan Gorilla V in relation to the spud can dimensions, spud can layout and cantilever loads.

Figure III RGV Spud Can Dimensions

Figure IV RGV Cantilever Loads

Figure V RGV Elevation

Figure VI RGV Plan View



Figure III



Figure IV



Figure V



Figure VI



APPENDIX 5: FRANKLIN WELLHEAD TOPSIDE STRUCTURAL DRAWING LIST

The following drawing list covers the primary structural framing for the existing Franklin Wellhead Topsides. These are provided in reference 3 and are included for the purposes of modelling a representative stiffness of the topside structures in analysis only:

Number Rev Title

KVAERNER DESIGN DRAWINGS AS BUILT

FRA-WD1-SGA-03101-001 Z06 FRANKLIN WELLHEAD PRIMARY STEEL GA PLAN ON LOWER DECK FRA-WD2-SGA-03102-001 Z07 FRANKLIN WELLHEAD PRIMARY STEEL GA PLAN ON MEZZANINE DECK FRA-WD3-SGA-03103-001 Z07 FRANKLIN WELLHEAD PRIMARY STEEL GA PLAN ON WEATHER DECK FRA-WDA-SGA-03104-001 Z07 FRANKLIN WELLHEAD ELEVATION ON TRUSS LINE 7 LOOKING NORTH FRA-WDA-SGA-03104-002 Z07 FRANKLIN WELLHEAD ELEVATION ON TRUSS LINE 8 LOOKING NORTH FRA-WDA-SGA-03104-003 Z06 FRANKLIN WELLHEAD ELEVATION ON TRUSS LINE 7X LOOKING NORTH FRA-WDA-SGA-03104-004 Z06 FRANKLIN WELLHEAD ELEVATION ON TRUSS LINE 7Y LOOKING NORTH FRA-WDA-SGA-03105-001 Z06 FRANKLIN WELLHEAD ELEVATION ON TRUSS LINE M LOOKING WEST FRA-WDA-SGA-03105-002 Z06 FRANKLIN WELLHEAD ELEVATION ON TRUSS LINE N LOOKING WEST FRA-WDA-SGA-03105-003 Z07 FRANKLIN WELLHEAD ELEVATION ON TRUSS LINE MX LOOKING WEST FRA-WDA-SGA-03105-004 Z06 FRANKLIN WELLHEAD ELEVATION ON TRUSS LINE P & R LOOKING WEST FRA-WDA-SGA-03106-001 I01 FRANKLIN WELLHEAD SECONDARY STEEL GA PLAN ON ESDV PLATFROM



APPENDIX 6: EXISTING TEPUK FRANKLIN WELLHEAD JACKET STRUCTURE DRAWING LIST

See Reference 5 for drawings in adobe format. These drawings are available from TEPUK in native format if required.



Number Rev Title

SAIPEM DESIGN DRAWINGS AS BUILT

FRA-JAC-SIR-2000.1 C02 FRANKLIN WHP A JACKET:MODIFICATIONS TO EXISTING DOCKING GUIDE M7 FRA-JAC-SIR-2001.1 C03 FRANKLIN WHP A JACKET:MODIFICATIONS TO EXISTING DOCKING GUIDE M8 FRA-JAC-SGA-16100.1 C04 FRANKLIN A JACKET:GEOGRAPHICAL LOCATION AND GENERAL NOTES FRA-JAC-SGA-16101.1 I03 FRANKLIN A JACKET:DRAWING INDEX FRA-JAC-SGA-16103.1 I05 FRANKLIN A JACKET:GENERAL DESIGN DATA:TEMPORARY CONDITION FRA-JAC-SGA-16103.2 I05 FRANKLIN A JACKET:GENERAL DESIGN DATA:OPERATING CONDITION FRA-JAC-SGA-16103.3 I05 FRANKLIN A JACKET:GENERAL DESIGN DATA:WORK OVER MODE FRA-JAC-SGA-16103.4 I04 FRANKLIN A JACKET:GENERAL DESIGN DATA JACK-UP CANTILEVERD DRILLING MODE FRA-JAC-SGA-16105.1 I02 FRANKLIN A JACKET:PERSPECTIVE FRA-JAC-SWJ-16107.1 C02 FRANKLIN A JACKET:GENERAL WELDING DETAILS:ACCESS FROM BOTH SIDES FRA-JAC-SWJ-16107.2 C02 FRANKLIN A JACKET:GENERAL WELDING DETAILS:ACCESS FROM ONE SIDE FRA-JAC-SWJ-16109.1 C02 FRANKLIN A JACKET:TYPICAL JACKET NODE DETAILS FRA-JAC-SGA-16111.1 I02 FRANKLIN A JACKET:LAYOUT OF JACKET AND JACK-UP AT MUDLINE FRA-JAC-SGA-16114.1 I02 FRANKLIN A JACKET:GENERAL ARRANGEMENT:PLANS FRA-JAC-SGA-16115.1 I03 FRANKLIN A JACKET:GENERAL ARRANGEMENT:ELEVATIONS ON ROWS M & N FRA-JAC-SGA-16116.1 I02 FRANKLIN A JACKET:GENERAL ARRANGEMENT:ROWS 3 AND 4 FRA-JAC-SGA-16117.1 I01 FRANKLIN A JACKET:GENERAL ARRANGEMENT:ELEVATIONS ON LOWER SECTION FRA-JAC-SPS-16120.1 C03 FRANKLIN A JACKET:HORIZONTAL FRAMING PLAN AT ELEVATION (-) 89.100 FRA-JAC-SPS-16121.1 C04 FRANKLIN A JACKET:HORIZONTAL FRAMING PLAN AT ELEVATION (-) 68.000 FRA-JAC-SPS-16122.1 C02 FRANKLIN A JACKET:HORIZONTAL FRAMING PLAN AT ELEVATION (-) 38.000 FRA-JAC-SPS-16123.1 C02 FRANKLIN A JACKET:HORIZONTAL FRAMING PLAN AT ELEVATION (-) 18.000 FRA-JAC-SPS-16124.1 C02 FRANKLIN A JACKET:HORIZONTAL FRAMING PLAN AT ELEVATION (+) 8.000 FRA-JAC-SPS-16126.1 C03 FRANKLIN A JACKET:VERTICAL FRAMING GRID LINE M:ELEVATION (+) 20.500 TO ELEVATION (-) 28.000 FRA-JAC-SPS-16126.2 C03 FRANKLIN A JACKET:VERTICAL FRAMING GRID LINE M:ELEVATION (-) 28.000 TO ELEVATION (-) 68.000 FRA-JAC-SPS-16126.3 C03 FRANKLIN A JACKET:VERTICAL FRAMING GRID LINE M:ELEVATION (-) 68.000 TO ELEVATION (-) 92.400 FRA-JAC-SPS-16128.1 C03 FRANKLIN A JACKET:VERTICAL FRAMING GRID LINE N:ELEVATION (+) 20.500 TO ELEVATION (-) 28.000 FRA-JAC-SPS-16128.2 C02 FRANKLIN A JACKET:VERTICAL FRAMING GRID LINE N:ELEVATION (-) 28.000 TO ELEVATION (-) 68.000 FRA-JAC-SPS-16128.3 C03 FRANKLIN A JACKET:VERTICAL FRAMING GRID LINE N:ELEVATION (-) 68.000 TO ELEVATION (-) 92.400 FRA-JAC-SPS-16130.1 C02 FRANKLIN A JACKET:VERTICAL FRAMING GRID LINE 7:ELEVATION (+) 20.500 TO ELEVATION (-) 28.000 FRA-JAC-SPS-16130.2 C02 FRANKLIN A JACKET:VERTICAL FRAMING GRID LINE 7:ELEVATION (-) 28.000 TO ELEVATION (-) 68.000 FRA-JAC-SPS-16130.3 C02 FRANKLIN A JACKET:VERTICAL FRAMING GRID LINE 7:ELEVATION (-) 68.000 TO ELEVATION (-) 92.400



Number Rev Title FRA-JAC-SPS-16132.1 C02 FRANKLIN A JACKET:VERTICAL FRAMING GRID LINE 8:ELEVATION (+) 20.500 TO ELEVATION (-) 28.000 FRA-JAC-SPS-16132.2 C03 FRANKLIN A JACKET:VERTICAL FRAMING GRID LINE 8:ELEVATION (-) 28.000 TO ELEVATION (-) 68.000 FRA-JAC-SPS-16132.3 C03 FRANKLIN A JACKET:VERTICAL FRAMING GRID LINE 8:ELEVATION (-) 68.000 TO ELEVATION (-) 92.400 FRA-JAC-SPS-16134.1 C03 FRANKLIN A JACKET:PILE SLEEVE S1 AND BRACING:ELEVATION (-) 68.000 TO ELEVATION (-) 92.400 FRA-JAC-SPS-16134.2 C03 FRANKLIN A JACKET:PILE SLEEVE S2 AND BRACING:ELEVATION (-) 68.000 TO ELEVATION (-) 92.400 FRA-JAC-SPS-16134.3 C03 FRANKLIN A JACKET:PILE SLEEVE S3 AND BRACING:ELEVATION (-) 68.000 TO ELEVATION (-) 92.400 FRA-JAC-SPS-16134.4 C03 FRANKLIN A JACKET:PILE SLEEVE S4 AND BRACING:ELEVATION (-) 68.000 TO ELEVATION (-) 92.400 FRA-JAC-SLO-16139.1 C02 FRANKLIN A JACKET:LOADOUT SHOE DETAILS FRA-JAC-SJM-16140.1 C02 FRANKLIN A JACKET:PILE SLEEVE DETAILS:SHEET 1 FRA-JAC-SJM-16140.2 C03 FRANKLIN A JACKET:PILE SLEEVE DETAILS:SHEET 2 FRA-JAC-SDT-16142.1 C02 FRANKLIN A JACKET:LEG INTERNAL RING STIFFENERS AND WATERTIGHT DIAPHRAMS FRA-JAC-SDT-16145.1 C02 FRANKLIN A JACKET:LEG FLOODING PENETRATION DETAILS FRA-JAC-SJM-16148.1 C02 FRANKLIN A JACKET:MUDMAT GENERAL ARRANGEMENT FRA-JAC-SJM-16149.1 C03 FRANKLIN A JACKET:MUDMAT DETAILS FRA-JAC-SCF-16152.1 C06 FRANKLIN A JACKET:PILE MAKE UP AND DETAILS FRA-JAC-SNP-16153.1 C05 FRANKLIN A JACKET:PILE MARKINGS ARRANGEMENT AND DETAILS FRA-JAC-SJC-16160.1 C02 FRANKLIN A JACKET:CONDUCTOR GUIDES SUPPORT AT ELEVATION (-) 68.000 FRA-JAC-SJC-16161.1 C02 FRANKLIN A JACKET:CONDUCTOR GUIDES SUPPORT AT ELEVATION (-) 38.000 FRA-JAC-SJC-16162.1 C02 FRANKLIN A JACKET:CONDUCTOR GUIDES SUPPORT AT ELEVATION (-) 18.000 FRA-JAC-SJC-16163.1 C02 FRANKLIN A JACKET:CONDUCTOR GUIDES SUPPORT AT ELEVATION (+) 8.000 FRA-JAC-SJC-16165.1 C04 FRANKLIN A JACKET:CONDUCTOR GUIDE DETAILS FRA-JAC-SPS-16170.1 C03 FRANKLIN A JACKET:LIFT TRUNNIONS:SHEET 1 FRA-JAC-SPS-16170.2 C03 FRANKLIN A JACKET:LIFT TRUNNIONS:SHEET 2 FRA-JAC-SDT-16172.1 C04 FRANKLIN A JACKET:INTERNAL RING STIFFENER DETAILS AT ELEVATION (-) 68.000 FRA-JAC-SDT-16173.1 C01 FRANKLIN A JACKET:INTERNAL RING STIFFENER AT ELEVATION (-) 68.000 WELD GRINDING DETAILS FRA-JAC-SDT-16174.1 C01 FRANKLIN A JACKET:PILE SLEEVE BRACE WELD GRINDING & PROFILING DETAILS FRA-JAC-SPS-16175.1 C02 FRANKLIN A JACKET:LOWER LIFTING PADEYES:SHEET 1 FRA-JAC-SPS-16175.2 C04 FRANKLIN A JACKET:LOWER LIFTING PADEYES:SHEET 2 FRA-JAC-SIR-16178.1 C03 FRANKLIN A JACKET:INSTALLATION AID LOCATION AND DETAILS FRA-JAC-SJA-16180.1 C02 FRANKLIN A JACKET:CATHODIC PROTECTION PLAN AT ELEVATION (-) 18.000 FRA-JAC-SJA-16181.1 C02 FRANKLIN A JACKET:CATHODIC PROTECTION PLAN AT ELEVATION (-) 38.000 FRA-JAC-SJA-16182.1 C02 FRANKLIN A JACKET:CATHODIC PROTECTION PLAN AT ELEVATION (-) 68.000 FRA-JAC-SJA-16183.1 C03 FRANKLIN A JACKET:CATHODIC PROTECTION PLAN AT ELEVATION (-) 89.100



Number Rev Title FRA-JAC-SJA-16185.1 C02 FRANKLIN A JACKET:CATHODIC PROTECTION GRID LINE M:ELEVATION (+) 20.500 TO ELEVATION (-) 28.000 FRA-JAC-SJA-16185.2 C02 FRANKLIN A JACKET:CATHODIC PROTECTION GRID LINE M:ELEVATION (-) 28.000 TO ELEVATION (-) 68.000 FRA-JAC-SJA-16185.3 C02 FRANKLIN A JACKET:CATHODIC PROTECTION GRID LINE M:ELEVATION (-) 68.000 TO ELEVATION (-) 92.400 FRA-JAC-SJA-16186.1 C02 FRANKLIN A JACKET:CATHODIC PROTECTION GRID LINE N:ELEVATION (+) 20.500 TO ELEVATION (-) 28.000 FRA-JAC-SJA-16186.2 C02 FRANKLIN A JACKET:CATHODIC PROTECTION GRID LINE N:ELEVATION (-) 28.000 TO ELEVATION (-) 68.000 FRA-JAC-SJA-16186.3 C02 FRANKLIN A JACKET:CATHODIC PROTECTION GRID LINE N:ELEVATION (-) 68.000 TO ELEVATION (-) 92.400 FRA-JAC-SJA-16187.1 C02 FRANKLIN A JACKET:CATHODIC PROTECTION GRID LINE 7:ELEVATION (+) 20.500 TO ELEVATION (-) 28.000 FRA-JAC-SJA-16187.2 C02 FRANKLIN A JACKET:CATHODIC PROTECTION GRID LINE 7:ELEVATION (-) 28.000 TO ELEVATION (-) 68.000 FRA-JAC-SJA-16188.1 C02 FRANKLIN A JACKET:CATHODIC PROTECTION GRID LINE 8:ELEVATION (+) 20.500 TO ELEVATION (-) 28.000 FRA-JAC-SJA-16188.2 C02 FRANKLIN A JACKET:CATHODIC PROTECTION GRID LINE 8:ELEVATION (-) 28.000 TO ELEVATION (-) 68.000 FRA-JAC-SJA-16189.1 C02 FRANKLIN A JACKET:CATHODIC PROTECTION:ELEVATION (-) 68.000 TO ELEVATION (-) 92.400 PILE SLEEVE AND BRACING FRA-JAC-SJA-16190.1 C02 FRANKLIN A JACKET:MUDMATS CATHODIC PROTECTION FRA-JAC-SJA-16193.1 C03 FRANKLIN A JACKET:CATHODIC PROTECTION:ANODE DETAILS:SHEET 1 FRA-JAC-SJA-16193.2 C02 FRANKLIN A JACKET:CATHODIC PROTECTION ANODE DETAILS:SHEET 2 FRA-JAC-SJW-16205.1 C04 FRANKLIN A JACKET:SEA ESCAPE LADDER GENERAL ARRANGEMENT AND DETAILS FRA-JAC-SAP-16210.2 C03 FRANKLIN A JACKET:APPURTENANCE:GENERAL ARRANGEMENT OPTION 2 FRA-JAC-SAP-16210.4 C03 FRANKLIN A JACKET:APPURTENANCE:GENERAL ARRANGEMENT OPTION 4 FRA-JAC-SAP-16211.1 C05 FRANKLIN A JACKET:APPURTENANCE:GENERAL ARRANGEMENT ELEVATION:SHEET 1 FRA-JAC-SAP-16211.2 C03 FRANKLIN A JACKET:APPURTENANCE:GENERAL ARRANGEMENT ELEVATION:SHEET 2 FRA-JAC-SAP-16216.1 C04 FRANKLIN A JACKET:APPURTENANCES SUPPORT AND GUIDE DETAILS:SHEET 1 FRA-JAC-SAP-16216.2 C04 FRANKLIN A JACKET:APPURTENANCES SUPPORT AND GUIDE DETAILS:SHEET 2 FRA-JAC-SAP-16216.3 C05 FRANKLIN A JACKET:APPURTENANCES SUPPORT AND GUIDE DETAILS:SHEET 3 FRA-JAC-SAP-16216.4 C02 FRANKLIN A JACKET:APPURTENANCES SUPPORT AND GUIDE DETAILS:SHEET 4 FRA-JAC-SAP-16230.1 C03 FRANKLIN A JACKET:16 INCH J-TUBE J1 GENERAL ARRANGEMENT FRA-JAC-SAP-16232.1 C03 FRANKLIN A JACKET:16 INCH J-TUBE J2 GENERAL ARRANGEMENT FRA-JAC-SAP-16234.1 C04 FRANKLIN A JACKET:16 J-TUBE J1 AND J2 BELLMOUTH AND MESSENGER WIRE DERAILS" FRA-JAC-SAP-16234.2 C02 FRANKLIN A JACKET:12.75 J-TUBE J3 AND J4 BELLMOUTH AND MESSENGER WIRE DETAILS" FRA-JAC-SAP-16236.1 C03 FRANKLIN A JACKET:12.75 INCH J-TUBE J3 GENERAL ARRANGEMENT FRA-JAC-SAP-16238.1 C03 FRANKLIN A JACKET:12.75 INCH J-TUBE J4 GENERAL ARRANGEMENT FRA-JAC-SAP-16242.1 C04 FRANKLIN A JACKET:J-TUBE SUPPORT AND GUIDE DETAILS SHEET 1 FRA-JAC-SAP-16242.2 C03 FRANKLIN A JACKET:J-TUBE SUPPORT AND GUIDE DETAILS SHEET 2 FRA-JAC-SAP-16242.3 C03 FRANKLIN A JACKET:J-TUBE SUPPORT AND GUIDE DETAILS SHEET 3 FRA-JAC-SAP-16242.4 C03 FRANKLIN A JACKET:J-TUBE SUPPORT AND GUIDE DETAILS SHEET 4



Number Rev Title FRA-JAC-SAP-16250.1 C04 FRANKLIN A JACKET:20 INCH SEAWATER LIFT CAISSON:ELEVATIONS AND DETAILS:SHEET 1 FRA-JAC-SAP-16250.2 C02 FRANKLIN A JACKET:20 INCH SEAWATER LIFT CAISSON:ELEVATIONS AND DETAILS:SHEET 2 FRA-JAC-SAP-16252.1 C03 FRANKLIN A JACKET:6 INCH SEWAGE DISPOSAL CAISSON ELEVATION AND DETAILS FRA-JAC-SNP-16260.1 C02 FRANKLIN A JACKET:UNDERWATER IDENTIFICATION MARKS:DETAILS FRA-JAC-SNP-16261.1 C02 FRANKLIN A JACKET:UNDERWATER IDENTIFICATION MARKS:ELEVATIONS FRA-JAC-SNP-16263.1 C02 FRANKLIN A JACKET:UNDERWATER IDENTIFICATION MARKS:PLANS FRA-JAC-SNP-16266.1 C03 FRANKLIN A JACKET:PAINTING AND PAINT MARK DETAILS:SHEET 1 FRA-JAC-SNP-16267.1 C03 FRANKLIN A JACKET:PAINTING AND PAINT MARK DETAILS:SHEET 2 FRA-JAC-SNP-16268.1 C03 FRANKLIN A JACKET:PAINT MARK ON CONDUCTORS:CAISSONS AND J-TUBES FRA-JAC-SIR-16280.1 C02 FRANKLIN A JACKET:GROUTING AND PACKER SYSTEM SCHEMATIC FRA-JAC-SIR-16282.1 C02 FRANKLIN A JACKET:PACKER INFLATION SYSTEM:TOP OF JACKET CONNECTION DETAILS FRA-JAC-SIR-16284.1 C02 FRANKLIN A JACKET:PACKER INFLATION SYSTEM:LOWER JACKET LEG DETAILS AND PENETRATIONS FRA-JAC-SIR-16286.1 C02 FRANKLIN A JACKET:GROUT AND PACKER INFLATION SYSTEM:PILE SLEEVE DETAILS AND PENETRATIONS FRA-JAC-SIR-16288.1 C02 FRANKLIN A JACKET:PACKER AND GROUT MANIFOLD DETAILS FRA-JAC-SIR-16290.1 C02 FRANKLIN A JACKET:PACKER INFLATION SYSTEM LAYOUT AND DETAILS AT ELEVATION (-) 89.100 FRA-JAC-SWS-16300.1 C02 FRANKLIN A JACKET:TEMPORARY WELLHEAD ACCESS PLATFORM:GENERAL ARRANGEMENT FRA-JAC-SWS-16301.1 C03 FRANKLIN A JACKET:TEMPORARY WELLHEAD ACCESS PLATFORM:FRAMING PLAN AT ELEVATION (+) 22.060:SHEET 1 FRA-JAC-SWS-16302.1 C03 FRANKLIN A JACKET:TEMPORARY WELLHEAD ACCESS PLATFORM:FRAMING PLAN AT ELEVATION (+) 22.060:SHEET 2 FRA-JAC-SWS-16304.1 C02 FRANKLIN A JACKET:TEMPORARY WELLHEAD ACCESS PLATFORM:ELEVATIONS AND SECTIONS:SHEET 1 FRA-JAC-SWS-16305.1 C02 FRANKLIN A JACKET:TEMPORARY WELLHEAD ACCESS PLATFORM:ELEVATIONS AND SECTIONS:SHEET 2 FRA-JAC-SWS-16306.1 C02 FRANKLIN A JACKET:TEMPORARY WELLHEAD ACCESS PLATFORM:GANGWAY SUPPORT DETAILS FRA-JAC-SWS-16307.1 C03 FRANKLIN A JACKET:TEMPORARY WELLHEAD ACCESS PLATFORM:DETAILS:SHEET 1 FRA-JAC-SWS-16308.1 C02 FRANKLIN A JACKET:TEMPORARY WELLHEAD ACCESS PLATFORM:DETAILS:SHEET 2 FRA-JAC-SWS-16309.1 C02 FRANKLIN A JACKET:TEMPORARY WELLHEAD ACCESS PLATFORM:SUPPORT DETAILS

FRA-JAC-SWS-16310.1 C02 FRANKLIN A JACKET:TEMPORARY WELLHEAD ACCESS PLATFORM:LEG ACCESS PLATFORM:FRAMING PLAN AT ELEVATION (+) 19.720

FRA-JAC-SWS-16311.1 C02 FRANKLIN A JACKET:TEMPORARY WELLHEAD ACCESS PLATFORM:LEG ACCESS PLATFORM:GRATING AND HANDRAIL PLAN

FRA-JAC-SWS-16312.1 C02 FRANKLIN A JACKET:TEMPORARY WELLHEAD ACCESS PLATFORM:STAIR GENERAL ARRANGEMENT AND DETAILS FRA-JAC-SWS-16313.1 C03 FRANKLIN A JACKET:TEMPORARY WELLHEAD ACCESS PLATFORM:PADEYE DETAILS AND WINCH SUPPORT POINTS

FRA-JAC-SWS-16315.1 C02 FRANKLIN A JACKET:TEMPORARY WELLHEAD ACCESS PLATFORM:GRATING AND HANDRAIL PLAN AT ELEVATION (+) 22.100:SHEET 1

FRA-JAC-SWS-16316.1 C02 FRANKLIN A JACKET:TEMPORARY WELLHEAD ACCESS PLATFORM:GRATING AND HANDRAIL PLAN AT ELEVATION (+) 22.100:SHEET 2

FRA-JAC-SHL-16318.1 C02 FRANKLIN A JACKET:TEMPORARY WELLHEAD ACCESS PLATFORM:HANDRAIL DETAILS FRA-JAC-SWS-16320.1 I01 FRANKLIN A JACKET:TEMPORARY WELLHEAD ACCESS PLATFORM:REMOVAL SEQUENCE



Number Rev Title FRA-WD3-SDT-16401.1 Z03 STRUCTURAL MODIFICATIONS TO WEATHER DECK PRIMARY MEMBER FOR FLOWLINE F4 THERMAL GROWTH FRA-WD2-SGA-16410.1 C02 MEZZANINE DECK -WELL SLOTS 5 & 8 SUPPORT FRAME FOR INTENSIFIER PANEL ARRANGEMENT & DETAIL FRA-WD2-SGA-16418.1 Z03 ANNULUS MANAGEMENT STUDY GENERAL ARRANGEMENT OF VALVE ACCESS PLATFORMS - WEST FRA-WD2-SGA-16419.1 Z03 ANNULUS MANAGEMENT STUDY : GENERAL ARRANGEMENT OF VALVE ACCESS PLATFORM

FRA-WD2-SDT-16420.1 C02 FRANKLIN WELLHEADS : ANNULUS MANAGEMENT STUDY STRUCTURAL ARRANGEMENT OF VALVE ACCESS PLATFORM - EAST

FRA-WD2-SDT-16420.2 C02 FRANKLIN WELLHEADS : ANNULUS MANAGEMENT STUDY STRUCTURAL ARRANGEMENT OF VALVE ACCESS PLATFORM - EAST - DETAILS

FRA-WD2-SDT-16420.3 C02 FRANKLIN WELLHEADS: ANNULUS MANAGEMENT STUDY STRUCTURAL DETAILS OF VALVE ACCESS PLATFORM - EAST FRA-WD2-SDT-16421.1 C02 ANNULUS MANAGEMENT STUDY GENERAL ARRANGEMENT OF VALVE ACCESS PLATFORM - WEST FRA-WD2-SDT-16421.2 C02 FRANKLIN WELLHEADS ANNULUS MANAGEMENT SYSTEM VALVE ACCESS PLATFORM - WEST. DETAILS

FRA-WD2-SGA-16422.1 R01 FRANKLIN WELLHEADS ANNULUS MANAGEMENT STUDY VALVE ACCESS PLATFORM -EAST - PLATFORM SUB-ASSEMBLIES

FRA-WD2-SHL-16423.1 C02 ANNULUS MANAGEMENT SYSTEM VALVE ACCESS PLATFORM - WEST - LADDER ARRANGEMENT FRA-WD2-SHL-16423.2 C02 ANNULUS MANAGEMENT SYSTEM VALVE ACCESS PLATFORM - WEST - HANDRAIL ARRANGEMENT FRA-WD2-SHL-16424.1 C02 DETAILS OF SUSPENDED VALVE ACCESS PLATFORMS HANDRAILS & GRATING : SHEET 1 OF 2 FRA-WD2-SHL-16424.2 C02 DETAILS OF SUSPENDED VALVE ACCESS PLATFORMS ACCESS LADDER : SHEET 2 OF 2 FRA-WD2-SDP-16425.1 R01 FRANKLIN WELLHEADS. LAYOUT OF ADDITIONAL MEZZ DECK PENETRATIONS FOR ANNULUS MANAGEMENT PIPEWORK FRA-WD1-SDT-16434.1 Z06 DETAILS OF CONDUCTOR RESTRAINTS FOR SLOT 4 FRA-WD1-SDT-16434.2 C01 FRANKLIN WELLHEADS DETAILS OF CONDUCTOR RESTRAINT FOR SLOT 4 SHEET 2 FRA-WD1-SDT-16435.1 C02 FIXING DETAILS OF MODIFICATIONS TO CONDUCTOR RESTRAINTS FOR SLOT 5 FRA-WD2-SHL-16437.1 C02 FRANKLIN WELLHEAD ANNULUS MANAGEMENT SYSTEM VALVE ACCESS PLATFORM (EAST) LADDER ARRANGEMENT FRA-WD2-SGA-16438.1 C02 ANNULUS MANAGEMENT SYSTEM VALVE ACCESS PLATFORM - EAST EXTENSION TO EXISTING PLATFORM GA FRA-WD2-SGA-16438.2 C02 ANNULUS MANAGEMENT SYSTEM VALVE ACCESS PLATFORM (EAST) EXTENSION

LEWIS OFFSHORE APURTENANCE FABRICATION DRAWINGS ST-F28-15-01 Z 20” SEAWATER LIFT CAISSON – GENERAL ARRGT AND DETAILS SHT 1 OF 2