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OISD-STD-138

First Edition March 1990

Amended Edition, September 2001 Revised Edition, September 2003

FOR RESTRICTED

CIRCULATION

INSPECTION OF

CROSS COUNTRY PIPELINES - ONSHORE

Prepared by

COMMITTEE ON DESIGN AND INSPECTION OF PIPELINES

OIL INDUSTRY SAFETY DIRECTORATE 7th Floor, New Delhi House,

27, Barakhamba Road, New Delhi – 110 001.

NOTE

OISD publications are prepared for use in the oil and gas industry under Ministry of Petroleum & Natural Gas. These are the property of Ministry of Petroleum & Natural Gas and shall not be reproduced or copied and loaned or exhibited to others without written consent from OISD. Though every effort has been made to assure the accuracy and reliability of the data contained in this documents. OISD hereby expressly disclaims any liability or responsibility for loss or damage resulting from their use. These documents are intended to supplement rather than replace their prevailing statutory requirements.

FOREWARD

The Oil Industry in India is 100 years old. Due to various collaboration agreements, a variety of international codes, standards and practices are in vogue. Standardisation in design philosophies and operating and maintenance practices at a national level was hardly in existence. This, coupled with feed back from some serious accidents that occurred in the recent past in India and abroad, emphasised the need for the industry to review the existing state of art in designing, operating and maintaining oil and gas installations. With this in view, the then Ministry of Petroleum and Natural Gas in 1986 constituted a Safety Council assisted by Oil Industry Safety Directorate (OISD), staffed from within the industry in formulating and implementing a series of self regulatory measures aimed at removing obsolescence, standardising and upgrading the existing standards to ensure safer operations. Accordingly OISD constituted a number of Functional Committees comprising of experts nominated from the industry to draw up standards and guidelines on various subjects.

The present standard on “Inspection of Cross Country Pipelines-Onshore”, was prepared by the Functional Committee on “Design and Inspection of Pipelines”. This document is based on the accumulated knowledge and experience of industry members and the various national and international codes and practices. This standard is meant to be used as a supplement and not as a replacement for existing codes and practices. It is hoped that the provision of this standard, if implemented objectively, may go a long way to improve the safety and reduce accidents in the Oil and Gas Industry. Users are cautioned that no standard can be a substitute for the judgement of a responsible and experienced engineer. Suggestions are invited from the users after it is put into practice to improve the standard further. Suggestions for amendments to this standard should be addressed to:

The Coordinator,

Committee on “Design and Inspection of Pipelines”, Oil Industry Safety Directorate,

7th Floor, New Delhi House, 27, Barakhamba Road, New Delhi - 110 001.

This standard in no way supersedes the statutory regulations of CCE, Factory Inspectorate or any other Statutory body which must be followed as applicable.

COMMITTEE ON

DESIGN AND INSPECTION OF PIPELINES

( First Edition April 1990 ) --------------------------------------------------------------------------------------------------------------------------------- Name Organisation --------------------------------------------------------------------------------------------------------------------------------- Leader 1. Sh.V.T. Karode Oil India Limited 2. Sh.R.A. Shanbhag * Indian Oil Corporation Limited Members 3. Sh.Rao Rudravajala Indian Oil Corporation Limited 4. Sh.S.K. Goyal Oil and Natural Gas Corporation Limited 5. Sh.C.N. Char Oil and Natural Gas Corporation Limited 6. Sh.E.M Bhumgara Hindustan Petroleum Corporation Limited 7. Sh.R.K. Mulla Hindustan Petroleum Corporation Limited 8. Sh.R.K. Dhadda Engineers India Limited 9. Sh.G.V.S. Saiprasad Gas Authority of India Limited 10. Sh.K.K. Dutta Oil India Limited 11. Sh.R.K. Baruah Oil India Limited Member Coordinator 12. Sh.M. Bhandari Oil Industry Safety Directorate In addition to the above, several other experts from the industry contributed in the preparation, review and finalisation of this document. * (Took over as Leader w.e.f June/89 on Shri Karode’s retirement from Oil India Ltd).

COMMITTEE ON

DESIGN AND INSPECTION OF PIPELINES

( First Revision September 2003 ) Name Organisation Leader 1. Sh.A. Sengupta Indian Oil Corporation Limited Members 2. Sh.G.S. Wankhede Bharat Petroleum Corporation Limited 3. Sh.KBS Negi Bharat Petroleum Corporation Limited 4. Sh.S.S.Patel GAIL India Limited 5. Sh.P.K.Pal Indian Oil Corporation Limited 6. Sh.C..K. Soman Kochi Refineries Limited Member Coordinator 7. Sh.R.N.Mittal Oil Industry Safety Directorate --------------------------------------------------------------------------------------------------------------------------------- In addition to the above, several other experts from the industry contributed in the preparation, review and finalisation of this document.

CONTENTS

Sl.No. Description Page No. 1.0 Introduction 1

2.0 Scope 1

3.0 Definitions 1

4.0 Pipeline Patrolling 1

5.0 Right of way inspection 1

6.0 Pipeline Crossing 2

6.1 Rail/Road Bridge and Suspended Crossing 2

6.2 Road and Highway Crossing 2

6.3 Submerged Crossing and Intertidal zone 2

7.0 Pigging 2

7.1 Descaling 2

7.2 Intelligent Pigging 2

8.0 Static Leak Test 2

9.0 Monitoring of External Corrosion 3

9.1 Pipe to Soil Potential(PSP) reading 3

9.2 Coating Health Surveys 3

10.0 Monitoring of Internal Corrosion 3

11.0 Checking of Leak Detection system 4

12.0 Weld repairs and Inspection 4

13.0 Hydrostatic Testing of Pipelines during repair 4

14.0 Pipeline Maintenance Equipment 4

15.0 Telecommunication System/Equipment 4

16.0 Telemetry System/Equipment 4

17.0 Safety Instrumentation 4

18.0 Valve 4

19.0 Pressure Relieving device 4

20.0 Storage Tank/Vessel 4

21.0 Fire Fighting Equipment 5

22.0 Load Lifting Equipment 5

23.0 Electrical Equipment 5

24.0 Rotating Equipment 5

25.0 Line Filters / Strainers 5

Sl.No. Description Page No.

26.0 Pressure Control / Surge Relief Valve 5

27.0 Safety Appliances 5

28.0 Pipeline Markers 5

29.0 Documentation 5

30.0 References 5

INSPECTION OF CROSS COUNTRY PIPELINES - ONSHORE

1.0 INTRODUCTION

Safety in petroleum installations and pipelines comes through continuous efforts at all stages and as such it can be ensured by observing that installations and piping are designed, constructed and tested as per recognised engineering standards and that they are periodically inspected and maintained. Systems and procedures for carrying out inspection and maintenance go a long way in ensuring safe operation

This standard stipulates that for Pipelines interconnecting various Industrial units, it shall be the responsibility of the OWNER of the Pipeline facility to ensure that the inspection procedures are followed irrespective of the arrangements between supplier and receiver.

2.0 SCOPE

This standard covers the minimum inspection requirements for Onshore Cross Country Pipelines (including pipelines interconnecting various industrial units), Pumps and Compressor Station equipment used in connection with transportation of crude petroleum, petroleum products and natural gas. This standard also covers the minimum inspection requirements of Telecommunication equipments, Instrumentations and SCADA associated with Onshore Cross Country Pipelines.

3.0 DEFINITIONS

i) CROSS COUNTRY PIPELINES For the purpose of this standard, Cross Country Pipelines are pipelines which carry crude petroleum, petroleum products, LPG and natural gas from producer facilities such as Tank Farms, Natural Gas Processing Plants, Refineries, Pump/Compressor Stations, Terminals (Marine, Rail and Truck) to other delivery and receiving points, designed and constructed

conforming to OISD 141, ANSI B 31.4 and ANSI B 31.8 or equivalent codes.

ii) SHALL The word 'Shall' is used to indicate that the provision is mandatory. iii) SHOULD The word 'Should' is used to indicate that the provision is recommendatory as per sound engineering practice.

4.0 PIPELINE PATROLLING

Each operating company shall maintain a periodic pipelines patrol programme to observe surface conditions on and adjacent to the Pipeline right of way, indications of leak, construction activity other than performed by the company and other factors affecting the safety and operation of the pipeline.

Patrolling (Aerial/Ground) of On-shore Cross Country Pipelines shall be carried out at the following intervals. i) Liquid Petroleum Pipelines in urban areas - Once in a fortnight. ii) Liquid Petroleum Pipeline in other areas - once in a month. iii) LPG pipelines - once in a week in urban areas and once in a month in other areas. iv) Natural Gas Pipelines - As specified in ANSI B 31.8 Clause 851.2

5.0 RIGHT OF WAY INSPECTION

The right of way shall be inspected and maintained once in a year to ensure clear visibility of ROW/ROU, access to maintenance crew along the ROW/ROU, valve locations and other pipeline facilities. All pipeline markers/kilometer posts and other signs/specific indication marks shall be maintained once in a year. API 1109,

ANSI B 31.4 & ANSI B 31.8 shall be referred for guidance.

6.0 PIPELINE CROSSING 6.1 RAIL / ROAD BRIDGE AND

SUSPENDED CROSSING Rail Bridge, Road Bridge, Suspended

crossings shall be inspected once in a quarter to check wear and tear of supports/structures and condition of coatings at the points where pipe exits and enters the ground. Ultrasonic thickness measurements shall be taken on exposed sections of the pipeline once in two years for the crude and gas pipelines and once in four years for product pipelines. Ultrasonic thickness measurement need not be done if intelligent pigging survey is carried out during this period. Thickness measurement shall be taken at 4 locations (i.e. 12, 3, 6 and 9 O'clock positions) at the exits, bends and at every ten metre interval of exposed piping. Where pipes are cased it shall be ensured that casings are free of water and muck.

6.2 ROAD AND HIGHWAY CROSSING

Road and Highway crossings shall be inspected once in a quarter. The carrier/casing pipe annulus shall be kept free of water.

6.3 SUB-MERGED CROSSING AND INTER-

TIDAL ZONE

Submerged crossing locations shall be inspected for erosion/washouts twice in a year i.e., prior to and after monsoon and topographic changes if any shall be recorded for corrective actions. Exposed length of pipeline, if any, falling in Inter-tidal Zones shall be inspected once in a quarter for checking the condition of coating and wrapping for taking corrective action.

7.0 PIGGING 7.1 DESCALING

The frequency of descaling of pipelines transporting crude

petroleum, petroleum products, LPG and natural gas shall be as under:

i) Non ATF Petroleum Product Pipelines - Once in six months. Ii) ATF pipelines also carrying other petroleum products - Once in a quarter. iii) Dedicated ATF Pipelines - Once in a year. v) Crude Oil Pipelines - Once in a quarter. vi) Gas Transmission Pipelines - Once in a year for wet gas and once in two years for dry gas. vi) LPG pipelines – as per OISD standard on cross country LPG pipelines. Record of quantity and quality of deposits (pig residue) collected after descaling shall be examined to monitor condition of the Pipeline and to determine subsequent frequency of pigging. The frequency of descaling shall, in no case, be more than two times as compared to the normal frequency of descaling given above.

7.2 INTELLIGENT PIGGING

The first inspection of a cross country pipeline by means of electronic / intelligent pigging shall be done within 10 years of its commissioning. The results of this inspection shall be compared with original commissioning data in order to assess the health of the pipeline and subsequent periodicity of intelligent pigging. The frequency of intelligent pigging shall, in no case, be more than 10 years.

8.0 STATIC LEAK TEST

Static Leak Test of the pipeline shall be performed once in five years using the liquid transported through the pipeline. The static leak test is used only to quantify the pressure and liquid containment capability of an existing Pipeline System at shutdown pressure. API 1110 (Section 3.0) shall be referred for guidance.

9.0 MONITORING OF EXTERNAL CORROSION 9.1 PIPE TO SOIL POTENTIAL (PSP)

READING

i) PSP readings at feeding points (Transformer Rectifier Units) shall be monitored fortnightly. ii) The PSP reading ( On potential ) at the test lead points for entire pipeline shall be taken once in a quarter. The PSP survey results shall be plotted graphically to identify and locate unprotected stretch of pipeline. The minimum pipe to soil potential shall be more negative than - 0.85 volts with respect to copper/copper sulphate half cell. In areas where anaerobic bacteria are active minimum PSP shall be more negative than - 0.95 volts instead of - 0.85 volts. Over protection of coated pipelines shall be avoided by ensuring that polarisation potential is below - 1.1 volts with respect to copper/copper sulphate half cells. Polarisation potential can be measured at a given location on a coated pipeline by measuring pipe to earth potential immediately (within the first second or two) after simultaneously interrupting the current output from all cathodic protection sources affecting that portion of the pipeline.

9.2 COATING HEALTH SURVEYS 9.2.1 Pearson / CAT & DCVG Survey shall

be carried out once in five years. 9.2.2 Continuous Potential Survey

Continuous Potential Logging (CPL) survey should be carried out once in five years.

9.2.3 Insulating Joint / Coupling

Inspection

Insulating joints and couplings shall be inspected once in a year.

9.2.4 External Corrosion Control for

above ground sections of Piping

Above ground piping and accessories shall be inspected visually once in a year for external corrosion. ANSI B.31.4 / B 31.8 shall be referred for guidance.

9.2.5 Soil Testing

If any industrial effluent is flowing over the ROW/ROU or any environmental change is noticed on the ROW, the soil samples shall be tested for determining the efficacy of the existing coating and wrapping of the pipeline.

9.2.6 Back Up Power For Cp System

Where ever the power supply from State Electricity Board to the CP system is poor, suitable back up power should be provided .

10.0 MONITORING OF INTERNAL CORROSION

Internal corrosion is a function of what the pipeline contains and transports.

Presence of corrosive constituents and

other contaminating impurities in the transported fluid may lead to internal metal loss in the pipeline resulting in general corrosion or pitting type of corrosion. Such constituents could be due to salinity of sea water, presence of carbon-dioxide together with moisture etc.

Presence of sulphur dioxide can lead to

serious sulphide stress cracking of steels which is essentially not a metal loss, but causes stepwise cracking in steel. For this type of corrosion, its mitigation can be done by injecting chemical inhibitors along with the product flow. The sulphide stress cracking can be mitigated by treating steel with certain alloying elements and controlling its hardness. Corrosion mitigation by using inhibitors may also help but only in case of certain specific types of fluid constituents. Another method of safeguarding against internal corrosion could be by providing lining on the inner wall of pipeline with an inert protective material compatible with the fluid transported.

The following schedules / activities shall be followed to monitor internal corrosion

i) Effectiveness of corrosion mitigation measures should be checked once in a year by analysing the corrosion coupon. ii) Electrical resistance probes should be installed for monitoring the effectiveness on corrosion mitigation measures and reading should be checked once in a quarter. iii) Whenever the sections of the pipeline are running overground, ultrasonic thickness measurements of the pipeline shall be taken as per clause 6.1 of this standard. iv) Whenever replacement to the pipeline are carried out, internal visual inspection shall be done to supplement ultrasonic thickness readings taken externally.

11.0 CHECKING OF LEAK

DETECTION SYSTEM If any leak detection system is installed on the pipeline system, it shall be checked for effectiveness of operation once in three months.

12.0 WELD REPAIRS AND INSPECTION

For section replacement, all weld repairs and inspection shall be carried out in accordance with API 1104, ANSI B.31.4 and ANSI B.31.8. API 2200, API 2201 and API 1107 shall be referred for guidance. All repaired welds shall be 100% radiographed.

13.0 HYDROSTATIC TESTING OF PIPELINES DURING REPAIR

Pre-tested pipe shall be used for all replacements in line with the requirements of OISD 141, ANSI B.31.4 and ANSI B.31.8 and API 1100.

14.0 PIPELINE MAINTENANCE

EQUIPMENT

The specialised pipeline maintenance equipment required for maintenance of pipeline shall be inspected once in a quarter.

15.0 TELECOMMUNICATION

SYSTEM / EQUIPMENT

i) System functional tests shall be carried out daily. ii) Telecommunication equipment shall be inspected as per manufacturer's recommendation.

16.0 TELEMETRY

SYSTEM/EQUIPMENT

i) System functional tests shall be carried out daily. ii) Telemetry equipment shall be inspected as per manufacturer's recommendation.

17.0 SAFETY INSTRUMENTATION

OISD 153, Maintenance and Inspection of Safety Instrumentation shall be referred.

18.0 VALVE

Valves shall be partially operated and serviced once in six months to ensure operability.

19.0 PRESSURE RELIEVING

DEVICE

OISD 132, Inspection of Pressure Relieving Devices, shall be referred.

20.0 STORAGE TANK / VESSEL

OISD 128, Inspection of Pressure Vessels and OISD 129, Inspection of Tankages, shall be referred.

21.0 FIRE FIGHTING EQUIPMENT

OISD 142, Inspection of Fire Fighting Equipment shall be referred.

22.0 LOAD LIFTING EQUIPMENT

All the lifting equipment, wire ropes, tackles etc. shall be inspected once in a year. Factory's Act, OISD-RP-205 shall be referred for guidance.

23.0 ELECTRICAL EQUIPMENT

OISD 137, OISD-RP-147 shall be referred.

24.0 ROTATING EQUIPMENT

Inspection of Rotating Equipment shall be carried out as per the following OISD Standards:

i) OISD 119 - Inspection of Pumps ii) OISD 120 - Inspection of Compressors iii) OISD 121 - Inspection of Drivers (excluding motors) iv) OISD 122 - Inspection of Fans, Blowers and Gear Boxes v) OISD 123 - Recommended Practice for Inspection and Maintenance of Rotating Equipment Components. vi) OISD 125 - Recommended Practice - Inspection and Maintenance of Mechanical Seals.

(Note - For Inspection of Gas Engines, Oil Engines and other prime movers above 150 KVA manufacturer's recommendation shall be followed.)

26.1 PRESSURE CONTROL /

SURGE RELIEF VALVE

Pressure Control / Surge Relief Valve shall be checked for operation once in a year.

27.0 SAFTEY APPLIANCES

Safety appliances provided against lightning, stray current interference from foreign objects at pipeline crossings etc. shall be maintained

once in six months and updated records kept.

28.0 PIPELINE MARKERS

The pipeline markers shall be maintained and inspected once in a year.

29.0 DOCUMENTATION

Formats for recording inspection findings shall be designed specifically for the equipment/instrument/system used in the Pipelines/System.

The following data also shall be available on record in all the Pipeline installations:

a) The basic data and parameters of the Pipelines/System such as Layout, Length, Diameter, Location of the different stations etc. b) A complete route strip map showing all the details of the passage of the Pipelines with respect to other public facilities such as roads, rivers, urban centres, rural areas etc. and all isolating valve locations.

c) List of various codes to which the Pipelines/system have been designed.

30.0 REFERENCES

This standard shall be read in conjunction with the following standards, codes and publications: i) API 1102 - Recommended Practice for Liquid Petroleum Pipelines Crossing Railroads and Highways. ii) API 1104 - Standard for Welding Pipelines and Related Facilities. iii) API 1105 - Practices for Oil and Product Pipelines. iv) API 1107 - Recommended Pipeline Maintenance Welding Practices.

v) API 1109 - Recommended Practice for Marking Liquid Petroleum Pipeline Facilities.

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