CP Specifications

8/10/2019 CP Specifications

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Cathodic Protection

Specification



LIST OF CONTENTS

1- SCOPE

2- DEVIATIONS

3- INDUSTRY

4- CATHODIC PROTECTION OF BURIED PIPELINES

A. GENERAL

B. DESIGN CRITERIA

5- THE SPECIFICATION

A. DC POWER SUPPLIES

B. ANODE BEDS

C. THE CABLES

D. TEST STATIONS

E. INSULATING MATERIALS

6- INSTALLATION



1- Scope:

This specification covers the minimum technical requirements covering the

design and installation of cathodic protection systems for buried pipelines.

Structures which shall be cathodically protected are:

a. underground pipes

b. buried steel valves

c. Crossing of: rivers, roads, and railway.

d. Crossing or parallel of existing pipelines.

2-Deviations:

Any deviation providing less than the minimum requirements of this standard

specification requires written approval from the engineer representative.

3- Industry standards, codes and references:

Those documents listed herein are guidelines or “practice” intended to



(2) Soil resistively survey (on the pipelines rout and for ground – bed

locations) shall be made including evaluation and shall be used for

cathodic protection design.

(3) Detailed engineering design and construction drawings.

(4) Technical satisfactions for materials and equipments of construction,

Transformer/Rectifiers, anodes and assembly, junction boxes, test

stations, cables, insulating Flanges or joints and other items as required.

(5) Operation manual, including test and adjustment procedures.

b- Design criteria:

1. Buried pipelines shall be cathodically protected with impressed current

systems.

2. The impressed current cathodic protection systems shall utilize surface

ground beds when applicable



4- The specifications:

A- DC power suppl ies:

Transformer / Rectifier units:

Oil – immersed transformer / rectifier units, in accordance with general

specifications The specification describes the requirements for an oil cooled

transformer - rectifier For powering a cathodic protection system.

a. Catalog cuts

Manufacturers, catalog cuts for each T/R unit supplied will include

information to verify that the materials meet the requirements of project

drawings and specification.

b- Rectifier operation and maintenance manual



- AC input 220v, 50Hz, full rated DC output shall be obtainable with an AC

input voltage at 5% below the nominal value.

- Continuous AC input voltage at 10% above nominal will not damage the

transformer, the diode bridge assembly or exceed any component ratings.

- Units will be oil cooled, cabinets will be sealed in accordance with / NEMA

250.

- Constant voltage control, by means of steps (5- Course, 5 – Fine).

- Silicon diode Rectifying elements, full wave bridge, protected by

semiconductor. Fuses, surge arrestors at the diode bridge.

- AC circuit Breakers.

- Separate AC and DC surge protection.- IP 55 min (with CSA, NEMA).

- Analog ammeter and voltmeter.

- Floor - mounted.



v- Anode material shall be selected from standard specification for cathodic

protection anodes.

1.Impressed current anodes:

1. Mixed metal oxide anode

- The anode shall be mixed metal oxide coated titanium tubes with 32 mm

(1.25- inch) diameter 1219 mm (48- inch) length.

- The anode shall be grade 1 / or 2 titanium per ASTM B -339.

- The minimum size anode wires is 10 mmP

2P strand copper conductor

HMWPE insulation.

2. Galvanic Anodes:(1) Upon completion of the detailed design, specify the following items:

- Type of anode material.

- Number of anodes



D- Test stations:

1- Potential test stations:

Test stations consist of test wires, a terminal box and a traffic box as

follows:

a- for the terminal box, use a five terminal Big Fink, mount on a 1.52 m

length of 76.2 mm diameter UV- Resistant plastic.

b- Pole mounted. Herein a guideline to establish a basis of design and

level of quality to be applied:

1. Test station for measuring (pipe - to - soil) potential shall be provided

at an interval of not more than one kilometer along the pipeline.

2. Test station for measuring (pipe – to – soil ) potential shall be providedand installed at the following locations:

Pipeline insulated cased crossings.

cased road crossing



c. Bond conductors shall be sized to carry the rated design current of the

bond box Minimum conductor size shall be (35) sq. mm. Strand copper

cable.

d. Bonding shall be provided at all locations where buried metallic pipelines

cross each Other.

e. Compensating current limitation unit for parallel pipelines.

3- Anode junction boxes

a. All cables inside anode lead junction boxes shall be identified with a

permanent and durable tag indicating the anode or the structure to

which they are connected. Nameplates shall also be affixed on all boxesto indicate the type of service; anode Lead junction boxes shall also

indicate the rectifier unit to which they are connected.

b junction boxes shall be located in non – hazardous areas whenever



b- Sleeves and washers

- sleeve mylar

- Washer phenolic

- Steel washer

o Insulating flange sets shall not be installed in buried portion of

pipeline.

o All locations where isolation of underground protected structures

from over ground structures is required.

o Surge diverters shall be used across each insulating joint or flange.

o Each insulating joint shall be megger - tested with (1000) VDC.

5- Installation:

a. Pipeline isolation: In accordance to standards.

b Electrical continuing bonding: In accordance to standards





d. Test stations, anode junction boxes and cathode junction boxes

i. All test station shall be installed and completed after the pipeline

backfilling operation.

ii. Cables inside test stations, anode junction boxes and cathode junction

boxes shall be identified with durable tag and labeled.

e. Cased crossing:

Casing insulators and end seals to be installed on any carrier pipe passing

through a pipe casing. They are designed to protect the carrier pipe coating

and electrically isolate the carrier pipe.

i. Casing spacers:

- Wooden skids are not acceptable as an alternative.

- Use injection molded PE insulators



8- Cathodic protection documentation:

a. C.P system design and calculations .

b. C.P system key diagrams.

c. C.P station layout cathodic protection equipment and materials

specifications.

d. C.P system installation specifications .

e. Manufacturers drawing and documentation including shop test

certificates.

f. C.P system on site test report.

g. All electrical and cathodic protection construction drawings.

h. All equipment catalogues, instruction, operation and maintenancemanuals.

i. List of the tests to be carried out on each component with details of test

procedure.



Building rooms for Batteries units' and also all accessories, Building

service room for guarders in far away areas to protect the system from

vandalism actions and construct BRC fence surrounded the whole

systems.

Bidders shall submit detailed technical offer for Solar Cathodic

Protection station and all relevant accessories.

Origin for the whole system of Solar Cathodic Protection station shall

be from (USA, Germany, Norway, Netherlands, France, and UK).

Contractor shall bear all expenses of a complete training program for

engineers and technicians for Five (5) persons and for ten (10) days

in the origin country include factory visit and training on maintenancethe Solar Cathodic Protection station.



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CP Specifications