WELCOME TO A PRESENTATION IN HPHT WELL

Date: **/**/2017

By Amalendu Das

DGM (D)

GROUND RULE

1. ALL MOBILE PHONES SHOULD BE IN SWITCH-OFF MODE OR SILENT MODE DURING THE

SESSION

2. THIS IS A KNOLEDGE SHARING SESSION

3. ALL SHOULD RESPECT INDIVIDUALS’ VIEW

4. DOUBT (IF ANY) WILL BE CLEARED (OR TRIED TO CLEAR) ONE BY ONE

5. EVERYBODY MAY SHARE THEIR KNOW-HOW RELATED TO THE SUBJECT

6. NUMBER OF SLIDES: 27, WILL BE COVERED IN 30 TO 35 MINS (IDEAL)

M/s Nabors Rig in Kakinada Flare during Drilling operation (not during testing)

600 0 F &

above

HPHThc (beyond naming category)

5000 F

u-HPHT

4000 F

HPHT

3000 F

10 KP 15KP 20 KP 25 KP &

above

Challenges of HPHT Wells

• Create higher rated MWD, LWD tools and other sub-surface Drilling

and Production tools to cope up with High Pressure and High

Tempt conditions.

• Overcoming the problems encountered during Drilling

• Cementing-cement Cracking, Micro Annulus, Zonal Isolation, High

density of drilling fluid-Stability, gel formation, Loss Circulation.

Challenges of HPHT Wells (cont.)

• Down hole pressure valves (above 350 deg F)

• Materials Gap-Elastomer stability at high temp, H2S Resistant alloys with

their corresponding strength

• Well control- Unplanned Events,

Uncertainty downhole P&T

Accidental Loads

Blowouts/uncontrolled flow.

• Narrow window between Pore Pressure and Frac-Pressure

• Hydrocarbon Influx and dissolution in oil based mud.

• Design of Casing-

– Higher Strength materials

– Design code mismatch between allowable stre

Challenges of HPHT Wells (cont.)

– Mismatch of material strength between hanger and casing.

• Issues for Well construction

– High Strength materials required with concurrent toughness/ductility.

– High Temperature condition impacts the strength of material.

– High Pressure-increase the risk of Burst and collapse failure.

• Corrosion resistant.

• No metallic seal stability in high temp.

• Combined effect of high temp and unpredicted extreme downhole

conditions on materials

WELL HEAD DESIGN CRITERIA TECHNOLOGY QUALIFICATION (TQ)

• PER API TR 17 TR 8 & API TR 1 PER 15K-1

• API RP 17 N & TECHNOLOGY REDINESS LEVEL (TRL)

• API PER 15K (API TR 1PER15K-1 Protocol for Verification and Validation of

High-pressure High-temperature Equipment, STANDARD by American

Petroleum Institute, 03/01/2013) SYSTEM ANALYSIS & TESTING

• NO CLEAR CODE, STANDARDS & REGULATIONS.

WELL HEAD DESIGN CRITERIA (cont.) WELL HEAD SURFACE EQUIPMENT

• FOR HAZARD IDENTIFICATION (HAZID/HAZOP) IS TYPICALLY

DIFFERENT

• API 16A: NOT SPECIFICALLY MENTIONED FOR DESIGN OF

HPHT PRESSURE EQUIPMENT

• SHEAR /SEALING COMPATIBILITY OF PRESSURE COMPONENTS

• FRACTURE & FATIGUE PRINCIPLE

WELL HEAD DESIGN CRITERIA (cont.) CORROSION TEST

WELL HEAD DESIGN CRITERIA (cont.) MANUFACTURERS’ PRESSURE TEST RECOMMENDATIONS

• API 14A – 11TH EDITION

• TEST PRESSURE – ABOVE 10 K: RWP+5K

BELOW 10 K: 150% OF RWP

• HPHT: 12 EDITION OF API 14A – MAY BE ADOPTED (ISSUED JAN

2015, EFFECTIVE JAN 2016)

• ASME FFS OR API 579

CEMENTING TECHNOLOGY

Example

• IN THICK SALT GYPSUM FORMATION: RECOMMENDATIONS – SUITABLE

CASING SHOULD BE-TP 155 STELL GRADE

• CEMENT SLURRY - 2.4 – 2.6 GM/CC (HI-DENSITY)

• SPACER – 2.4 – 2.65 GM/CC (SALT TOLERANT)

CEMENTATION: POST CRACK DESIGN

• CAP ROCK FAILURE: CEMENT CRACK DUE TO SHRINKAGE – VOLUMETRIC

CHANGE AND TENSION ON CEMENT

• EARLIER DESIGN: CONSIDERED STRESS ONLY-NO STRESS ALLOWED. BUT

NOW, CONSIDERED STRAIN-LIMITED PLASTIC STRAIN ALLOWED.

• MICRO-CRACK - 1/1000” (25.4 MICRON) OF WIDTH IS ALLOWABLE

(RECOMMENDED).

CEMENTATION: POST CRACK DESIGN (CONT.)

• CRACK STARTS AT 3KSI (kilo pounds per sq inch) OF DIFFERENTIAL

PRESSURE. 10 KSI DIFF PRESSURE IS ALLOWABLE (RECOMMENDED)

• DIFFERENTIAL PRESSURE: DIFFERENCE BETWEEN INTERNAL PRESSURE

(INSIDE CASING) AND EXTERNANAL PRESSURE (FROM OUT SIDE OF

CEMENT COLUMN)

• ALSO CRACK DEVELOPED DUE TO RATE OF TEMPERATURE RISE (HEATING

RATE). IF HEATING RATE INCREASES, THE FAILURE RATE ALSO INCREASES

(STEEP GRADIENT).

CEMENTATION: POST CRACK DESIGN (CONT.)

• UNIQUE DESIGN METHODOLOGY:

a) STRESS ANALYSIS

b) GAS MIGRATION ADVISOR

c) INTEGRATED EVALUATION

d) LOSS CIRCULATION PILL ADVISOR

e) HYDRAULIC SIMUTATOR (BACK BONE)

f) LABORATORY & COMPUTER MODELING (NOT YET DEVELOPED TO

MEET ACTUAL SITUATION)

CEMENTATION: POST CRACK DESIGN (CONT.)

• IDEAL CEMENT PROPERTY (?):

TENSILE STRENGTH: 1500 PSI

COMPRESSIVE STRENGTH: 15000 TO 20000 PSI

WELL CONTROL RULES

• RESPONSE TO GULF OF MAXICO INCIDENT (MACANDO): GUIDELINE - CFR TITLE

30 (PARTS 200 – 299).

• STRESSED ON

a) DRILLING MARGINS

b) API STANDARDS

c) REAL TIME MONITORING

d) CASING/CEMENTING

e) BOP EQUIPMENT

f) CONTAINMENT

g) INSPECTION/MECHANICAL INTEGRITY

h) ECONOMIC ANALYSIS

WELL CONTROL RULES (CONT.)

• Unintended Consequences may increase risk and decrease safety

• Unachievable and Unrealistic Implementation Period

• Additional Administrative Burden for BSEE

• BOP requirements beyond API Standard 53

• All at once Inspection and Certification of BOP

• Drilling Margins

• RTM

WELL CONTROL RULES (CONT.)

• UNDER CFR TITLE 30

• EXAMPLES:

a) PART 250. 735(a): SURFACE ACCUMULATOR CAPACITY – 1.5 TIMES

OF FLUIDE VOLUME UNDER ALL OPERATING CONDIONS OF BOPS

AGAINST MASP.

b) PART 250. 734. 6(v): EMERGENCY DISCONNECT SEQUENCE.

c) PART 250. 730(b), 739(d): TRAINING & QUALIFICATION.

d) PART 250. 734(a)(1), (a)(16)(i): BOP

FIVE YEAR INSPECTION-CFR PART 250 Comment from Cameron

SURFACE ACCUMULATOR CAPACITY-CFR PART

250 (Comment from Cameron cont.)

EMERGENCY DISCONNECT SEQUENCES-CFR

PART 250

The danger of this is that it could severely restrict our ability to operate

TRAINING AND QUALIFICATION-CFR PART 250

WELL CONTROL

WELL CONTROL -CFR#30 PART 250

API STANDARDS & SPECIFICATIONS

COMMENTS

NO CLEAR CODE, STANDARDS & REGULATIONS TILL DATE

FOR HPHT CATEGORY WELLS.

IT IS STILL IN REASERCH STATE (TRIAL AND ERROR METHOD IN SOME AREAS)

THANK YOU