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OISD STANDARD - 139 First Edition March 1990

Amended Edition, September 2001

FOR RESTRICTED CIRCULATION

No.

INSPECTION

OF

PIPELINES-OFFSHORE

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 & Chemicals. These are the property of Ministry of Petroleum & Chemicals 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.

Note 3 in superscript indicates the modification/changes/addition based on the amendments approved in the 19th Safety Council meeting held in September, 2001July, 1999

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 serious 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 Pipelines - Offshore” was prepared by the Functional Committee on “Design and Inspection of Pipelines”. This standard 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 of “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

List of Members

-------------------------------------------------------------------------------------------------------------------------------------- Name Designation & Position in Organisation Committee -------------------------------------------------------------------------------------------------------------------------------------- 1. Sh.V.T. Karode Chief Eng. (P/L), OIL Leader 2. Sh.R.A. Shanbhag GM (Proj), IOCL (P/L) Member/ Leader * 3. Sh.Rao Rudravajala COM, IOCL (P/L) Member 4. Sh.S.K. Goyal DGM, ONGC Member 5. Sh.C.N. Char CE (C& M), ONGC Member 6. Sh.E.M Bhumgara DGM, (T&P/L), HPCL Member 7. Sh.R.K. Mulla COM (P/L), HPCL Member 8. Sh.R.K. Dhadda Manager (P/L), EIL Member 9. Sh.G.V.S. Saiprasad Sr.Manager (P/L), GAIL Member 10. Sh.K.K. Dutta Dy.CE (P/L), OIL Member 11. Sh.R.K. Baruah SE (M), OIL Member 12. Sh.M. Bhandari Jt.Director, OISD Member Co-Ordinator -------------------------------------------------------------------------------------------------------------------------------------- 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).

INSPECTION OF PIPELINES-OFFSHORE

CONTENTS SECTION PAGE NO. 1.0 Introduction 2.0 Scope 3.0 Definitions 4.0 Inspection items of Offshore Pipelines/System 5.0 Intelligent Pigging 6.0 Weld repair and Inspection 7.0 Hydrostatic testing of Pipelines 8.0 Inspection items of Single Buoy Mooring System 9.0 Documentation 10.0 References

INSPECTION OF PIPELINES - OFFSHORE

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. 2.0 SCOPE This standard covers the minimum inspection requirement for offshore pipelines used in the transportation of crude petroleum, petroleum products and natural gas. This also covers minimum inspection requirements of Telecommunication equipment Instrumentation, Fire Fighting equipment and Load Lifting equipment associated with the offshore pipelines. The marginal onshore portion of offshore pipelines, if any, shall be governed by OISD-138. This standard also includes minimum inspection requirements of Single buoy mooring system (SBM). 3.0 DEFINITIONS i) OFFSHORE PIPELINES

Offshore pipelines are those pipelines which carry crude petroleum or its products or natural gas from producing sources, such as, well-head platforms or from Single buoy mooring system to main platforms in the offshore and are transporting crude petroleum or it product or natural gas from main platform or Single buoy mooring system to the place where facilities are available to receive them on hand.

ii) OFFSHORE

Areas beyond the line of ordinary high water, along that portion of the coast that is in direct contact with the open seas and beyond the line marking the seaward limit of inland coastal waters.

iii) SINGLE BUOY MOORING SYSTEM

Single buoy mooring system is a terminal system for loading/unloading of crude petroleum and other petroleum products from ocean going tankers within the environmental conditions existing at the installation area.

iv) SHALL

The word 'Shall' is used to indicate that the provision is mandatory.

v) SHOULD

The word 'Should' is used to indicate that the provision is recommendatory as sound engineering practice.

4.0 INSPECTION ITEMS OF OFFSHORE PIPELINES/SYSTEM The following are the various inspections that shall be carried out to ensure safe operation of Offshore Pipelines/System. 4.1 FREE SPAN SURVEY Free Span Survey shall be carried out annually. 4.2 LATERAL DISPLACEMENT SURVEY Lateral Displacement Survey shall be carried out annually. 4.3 DESCALING OF PIPELINES (PIGGING) Pipelines transporting crude petroleum and liquid petroleum products shall be descaled annually. Pigging record shall be maintained. Pig residue collected after descaling shall be examined to monitor the condition of the pipeline and to determine the subsequent frequency of descaling. 4.4 INSPECTION OF SACRIFICIAL ANODE Sacrificial anode shall be inspected once in three years.

4.5 CONTINUOUS POTENTIAL SURVEY Continuous Potential Logging survey shall be done once in five years. 4.6 DEBRIS CLEANING Debris cleaning should be done once in six months. 4.7 CEHCKING OF LEAK DETECTION

SYSTEM Leak Detection System shall be checked and calibrated for accuracy and effectiveness of operation once in three months. 4.8 INSPECTION OF VALVE Valves shall be partially operated and inspected once in six months to ensure operability at all times. 4.9 INSPECTION OF LOAD LIFTING

EQUIPMENT All load lifting equipment, wire ropes, tackles etc. shall be inspected once in year Factory's Act shall be referred for guidance. 4.10 INSPECTION OF TELECOMMUNICATION

SYSTEM/EQUIPMENT i) System functional tests shall be carried

out daily. ii) Telecommunication equipment shall be

inspected as per manufacturer's recommendation.

4.11 INSPECTION OF TELEMETRY

SYSTEM/EQUIPMENT i) System functional tests shall be carried

out daily. ii) Telemetry equipment shall be inspected

as per manufacturer's recommendation. 4.12 INSPECTION OF FIRE FIGHTING EQUIPMENT

OISD 142, Inspection of Fire Fighting

Equipment, shall be referred. 4.13 INSPECTION OF SAFETY INSTRUMENTATION

OISD-153, Maintenance and Inspection

of Safety Instrumentation, shall be referred.

5.0 INTELLIGENT PIGGING The Pipeline should be inspected once in 5 years for corrosion / dents / pits etc. by means of electronic / intelligent pigging Note 3. The results of subsequent inspections shall be compared with original commissioning date in order to assess the health of the pipeline and subsequent periodicity of intelligent pigging. 6.0 WELD REPAIR AND INSPECTION All weld repair and inspection shall be carried out in accordance with provisions of OISD 141 and API 1104, API 1107, API 2200, API 2201 shall be referred for guidance. 7.0 HYDROSTATIC TESTING OF PIPELINES 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 Note 3. 8.0 INSPECTION ITEMS OF SINGLE

BUOY MOORING SYSTEM The following are the various inspections that shall be carried out to ensure safe operation of Single Buoy Mooring System. 8.1 DAILY INSPECTION The following items shall be inspected daily i) Free flotation of buoys ii) Draft iii) Free movement of rotating assembly. 8.2 WEEKLY INSPECTION The following items shall be inspected weekly i) Mooring ropes and ancillary equipment

(e.g. supporting buoys, anti chafe chains, wire ropes, hawser float, chain link on the turn table of buoys etc.) for any defect.

ii) Batteries iii) Navigational aids 8.3 MONTHLY INSPECTION Visual inspection of buoys and equipment for external corrosion, shall be carried out once in a month. 8.4 QUARTERLY INSPECTION

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