DPR P-1P
GUIDELINES AND PROCEDURES FOR THE DESIGN, CONSTRUCTION, OPERATION AND MAINTENANCE OF OIL AND GAS PIPELINE SYSTEMS IN NIGERIA- 2007
TABLE OF CONTENT Purpose
3
Scope
3
Basic Symbols
4
Section 1- Basic Pipeline Statutory Approvals
6
Section II- Liquid Petroleum Transportation Systems
13
Section III – Gas Transmission and Distribution Systems
23
Section IV- Procedure for Upgrading and / or Change of Service For Pipeline System
30
Section V- Procedure for Discontinuation, Abandonment and Resumption of Operation of Pipeline Systems
32
Section VI- Flow-line, Pipeline & Riser Systems for Offshore Operations
34
Section VII – Open Access Pipeline Systems
36
Section VIII- Miscellaneous
36
Definitions
38
Index
41
2
TABLE OF CONTENT Purpose
3
Scope
3
Basic Symbols
4
Section 1- Basic Pipeline Statutory Approvals
6
Section II- Liquid Petroleum Transportation Systems
13
Section III – Gas Transmission and Distribution Systems
23
Section IV- Procedure for Upgrading and / or Change of Service For Pipeline System
30
Section V- Procedure for Discontinuation, Abandonment and Resumption of Operation of Pipeline Systems
32
Section VI- Flow-line, Pipeline & Riser Systems for Offshore Operations
34
Section VII – Open Access Pipeline Systems
36
Section VIII- Miscellaneous
36
Definitions
38
Index
41
2
1.1.0
PURPOSE.
These Guidelines are issued pursuant to the provision of sections 33 & 34 of the Oil Pipeline Act CAP 338 of the Law of the Federation of Nigeria 1990. It prescribes
1. The procedure to be followed to obtain all necessary licenses and ap provals for the Design and construction of oil and gas pipelines. 2. The guidelines to follow during the construction, commissioning, operation and maintenance of pipelines and their ancillary installations.
1.1.1
SCOPE
This guideline shall be applicable to all pipeline (section 11(2) Oil pipeline acts Cap 338 LFN 1990) systems employed for the service of transporting hydro-carbon fluid or fluids associated with operations related to Petroleum exploitation, production, refinery and product distribution. Open access pipeline systems shall observe any additional statutory provisions of the Open access statutory framework which are outside the scope of this guideline.
1.1.2
SECTION 11(2) OIL PIPELINE ACTS CAP 338 LFN 1990
Section 11(2) of the Oil Pipeline Act Cap 338 LFN 1990 defines pipeline as a means for the conveyance of mineral oils, natural gas and any derivatives or component, and any substance (including steam and water) used or intended to be used in the production or refining or conveying of mineral oils, natural g as and any of their derivatives de rivatives or components.
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BASIC SYMBOLS & ABBREVIATED TERMS
ANSI- American National Standard ASME- American Society of Mechanical Engineers ASTM- American Society for Testing & Material AGA- American Gas Association BFD- Basis for Design CEP- Community Engagement Plan DSAW- Double Submerged Arc Welded EIA- Environmental Impact Assessment ERW- Electric Resistance Welded FLR- Flow-line, Pipeline & Riser ITP- Inspection Test Plan MFR- Melt Mass Flow-Rate MOSR- Mineral Oil and Safety Regulation NACE- National Association of Corrosion Engineers NDR- National Data Repository NDT- Non-Destructive Test OPLL- Oil Pipeline License PFS- Process Flow-Scheme P&ID- Process and Instrumentation Diagram PQR- Procedure Qualification Record PRMS- Pressure Reduction and Metering Station PTS- Permit To Survey RBI- Risk Based Inspection ROW- Right of Way SCAW- Shielded Core Arc Welded SDR- Standard Dimension Ratio SOW- Scope of Work 4
TSC- Technical Safety Control WPS- Welding Procedure Specification
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SECTION I BASIC STATUTORY PIPELINE APPROVALS 1.2.1
PERMIT TO SURVEY A PIPELINE ROUTE
It shall be mandatory for the route of the proposed flow-line or pipeline to be surveyed or that of an existing pipeline to be re-surveyed before the grant of an Oil Pipeline Licence or the renewal of an expired licence.
For the purpose of this survey, a Permit to Survey shall be obtained in accordance with the provisions of Sections (4) and (5) of the Oil Pipeline Act CAP 338.
An application for a Permit to Survey shall be accompanied by the specified number of copies of the topographical map of the pipeline drawn on Scale 1:50,000 for pipelines of length up to 50 kilometer and 1:100,000 for pipelines of lengths between 50 kilometer and 100 kilometer and 1:250,000 for pipelines above 100 kilometer in length. Topographical maps shall be presented in a GIS format developed with Minna as a georeference datum.
1.2.2. LICENCE TO CONSTRUCT AND OPERATE PIPELINES.
An Oil Pipeline licence should be applied for within the validity of the Permit to Survey for the purpose of constructing and operating the proposed pipeline. In this regard, the provisions of Part III of the Oil Pipelines Act shall be followed in making such applications in addition to which the following requirements shall be fulfilled: 1.2.2.1 A statement indicating the service that the pipeline will render 1.2.2.2 The technical specifications of the proposed pipeline 1.2.2.3 The characteristics of the fluid to be conveyed through the pipeline 1.2.2.4 The total estimated cost of construction. 1.2.2.5 The List of the prospective construction companies being considered for the construction of the pipeline shall be submitted to the Department of Petroleum Resources for
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confirmation of companies’ accreditation and eligibility to render such services, in accordance with the Provisions of the Petroleum (Drilling and Production) regulations. 1.2.2.6 Ten copies of a detailed survey description of the proposed pipeline Right of Way in accordance with the Nigerian National Grid, indicating the width of the right of way with the coordinates (In approved geo-ditic formats) of the various points of intersection shall be submitted to the Director of Petroleum Resources. 1.2.2.7 Two copies of the plan of the pipeline showing the following: i)
The proposed route of the pipeline marked in red, with sections and quarter sections shown.
ii)
The location of each point at which there is a change in any of the following parameters: (a) Outside or nominal diameter of the pipeline (b) Wall thickness of the line pipe material (c) Type and Grade of line pipe. (d) Designed maximum operating pressure.
iii)
Direction of fluid flow along the pipeline
iv)
The locations indicated by symbols of any installations along the pipeline.
v)
The locations of the points at which other pipelines would be crossed by the new pipeline indicating the owner of the pipeline to be crossed.
vi)
The relative position of any existing pipeline or pipeline in an adjacent right of way within 100 meters should be indicated stating the name of the owner of such a pipeline.
vii)
The regional topography of the area along the pipeline route within a distance of 100 meters on both sides should be indicated including any watercourses to be crossed.
1.2.2.8 Two copies of the plan of the pipeline showing the following details: (a) Location of any anchors or expansion loops (b) Location and operating details of corrosion prevention devices, main line valves and any emergency shut down devices. (c) Pig launching and receiving points and any tie-in points with operating details.
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1.2.2.9 A hydraulic profile of the pipeline indicating the position of any pumping or booster stations and velocity profile (indicating erosional velocity boundaries).
1.2.2.10 For the ancillary facilities along the pipeline or its terminal ends such as compressor stations, manifolds, meter banks etc., a general description of the facility and its proposed design / operational parameters shall be given.
1.2.2.11 Two copies of the plan and profile of the pipeline showing the manner in which any highway, railroad, water way or other pipeline lying along the route would be crossed.
For the purpose of renewal, a photocopy of the expiring licence with the relevant attachments (shedule1&2) and a copy of the most recent pipeline integrity report shall be forwarded alongside the application for renewal of the licence.
1.2.3
CONCEPTUAL DESIGN
All pipeline development projects shall duly obtain an approval for the conceptual design prior to commencement of detailed design and construction. Application for approval of conceptual design shall be forwarded to the Director of Department of Petroleum Resources with the following deliverables: 1.2.3.1 Basic concept adopted for the development of the proposed pipeline system 1.2.3.2 Scope of work for the proposed pipeline development project 1.2.3.3 The design basis of the pipeline system 1.2.3.4 The approved technical specification for the proposed pipeline development project 1.2.3.5 A preliminary plan and profile for the proposed pipeline system 1.2.3.6 A copy of the approved FDP associated with this pipeline project where applicable 1.2.3.7 A copy of preliminary Environmental Impact Assessment 1.2.3.8 Basic concept of leak detection and general pipeline integrity monitoring 1.2.3.9 A copy of the planned organogram of the project execution / management team 1.2.3.10 A copy of the planned local content program for the proposed project
Company shall be requested to make a formal presentation of its conceptual design to the Department at-least a month after the receipt of above deliverables.
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The Department of Petroleum Resources shall thereafter communicate approval of conceptual design for the proposed pipeline development project. Where such approval will not be granted, the Department shall notify the company not more than one (1) month from the date of the presentation why such approval shall not be granted. An approved conceptual design shall form the basis for the development of the proposed pipeline system. Where a variation from the conceptual design is considered necessary in the subsequent phases of the project, a re-validation of the concept will be requested for and granted by the Director of Petroleum Resources.
1.2.4
DETAILED DESIGN
All pipeline development projects shall duly obtain an approval of the detailed design prior to commencement of fabrication of line pipes and construction of pipeline system. Application for approval of detailed design shall be forwarded to the Department of Petroleum Resources with the following deliverables: 1.2.4.1 Approved for construction PFS with material balances of pipeline system inclusive of the pigging facilities 1.2.4.2 Approved for construction P&ID for the pipeline system 1.2.4.3 Plan and profile of the pipeline system showing manner of crossings, pipeline marker positions, Pipeline grade, cathodic protection, line sectionalization valve stations, etc. 1.2.4.4 An arc GIS spatial grid of the pipeline system with reference to Minna Datum 1.2.4.5 A copy of the QA /QC approved for the project execution 1.2.4.6 A copy of the major engineering, & Technical Safety control (TSC) reviews conducted within the detailed design phase. 1.2.4.7 A copy of the pipeline construction plan inclusive of WPS / PQR 1.2.4.8 A copy of the technical data sheets for pipeline fittings / accessories 1.2.4.9 A copy of the hydraulic chart as well as velocity profile for the proposed pipeline system 1.2.4.10 A copy of the approved manufacturing Inspection plan for fabrication of line pipes / coating, as well as pipeline fittings / accessories. 1.2.4.11 Where line pipes shall be procured as long lead items, it shall be necessary for the licensee to notify the Department of all proposed manufacturing Inspection programs atleast six weeks prior to commencement of p ipe mill activities and make arrangements for the full participation of the Director’s representatives. Representatives shall endorse as witness in-factory quality assurance plan of the line pipes and pipeline fittings. 9
1.2.4.12 A copy of the stress / fatigue analysis of the pipeline system. 1.2.4.13 A copy of blow-down and de-pressurization plan for the pipeline system. 1.2.4.14 Leak detection and surveillance plan for the pipeline system 1.2.4.15 A copy of EIA approval 1.2.4.16 A copy of the proposed pipeline de-commissioning plan The Department of Petroleum Resources shall convey approval of detailed design for the proposed pipeline development project at-least one (1) month from the date of the receipt of complete detailed design approval dossier. Where such approval will not be granted, the Department shall notify the company not more than six (6) weeks from the date of receipt of application why such approval shall not be granted.
1.2.5
OPERATION & MAINTENANCE PLAN
All pipelines licensed for operation within the provisions of the oil pipeline act in Nigeria shall henceforth obtain an approval for the operation and maintenance plan for every pipeline system. Application for approval of operation and maintenance plan shall be accompanied with the following: 1.2.5.1 A copy of the operation and maintenance plan of the pipeline system
1.2.6
COMMISSIONING
Hydrocarbon shall not be introduced into any newly constructed or upgraded pipeline system without the commissioning approval of the Depa rtment of Petroleum Resources. Commissioning approval shall be granted to any pipeline system that has met the following conditions: 1.2.6.1 An application has been forwarded for grant of commissioning approval 1.2.6.2 The pipeline development project has met other necessary statutory requirements as reflected in the pipeline compliance plan of the project. 1.2.6.3 The pipeline has been successfully pre-commissioned.
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1.2.7
SPECIAL CASES OF APPROVAL
1.2.7.1 Abandonment Plan shall be applied for in situation where construction of a pipeline system shall require any form of abandonment. Section V of this document shall apply. In addition application shall be accompanied with a processing fee of N 50,000:00 made payable to the Department of Petroleum Resources.
1.2.7.2 Discontinuation of Use or Change of Service for any pipeline system shall be effected only upon the approval of the Department of Petroleum Resources. Section V of this document shall apply. In addition application shall be accompanied with a processing fee of N 50:00 made payable to the Department of Petroleum Resources.
1.2.7.3 Change of Diameter At OPLL shall attract a fee of N 50:00 line for a change of proposed diameter at OPLL stage from PTS.
1.2.7.4 Re-Validation of OPLL shall be effected for any pipeline works that are conducted within the validity period of any existing OPLL. The following shall be supplied by a pipeline licensee at-least one (1) month prior to commencement of any such works on an existing pipeline: 1. Scope of work 2. Objective 3. Scheduled 1- Survey Description of existing pipeline ROW 4. Schedule 2 – Technical Specification of the pipeline system 5. Schedule of planned work.
1.2.8
EXCEPTIONS
Exceptions to some of the above statutory approvals can be considered, where the pipeline licensee supplies sufficient justification within a reasonable time frame. As a general note however the following exceptions shall apply: 1. OPLL shall not be required for pipelines classified as flow-lines upstream of any manifold and being of such length that third party interference is absent. 11
2. OPLL shall not be required for any pipeline used for blow-down o r depressurization purposes of a process facility.
SECTION II LIQUID PETROLEUM TRANSPORTATION PIPING SYSTEMS
2.1.0 DESIGN CRITERIA: Reference Code ANSI /ASME B 31.4
The design criteria prescribed herein shall apply to new pipeline systems, relocation or replacement and upgrading of existing pipelines. a) The two commonly acceptable grade of line pipes for this service shall be either those materials conforming with the ASTM A 106 Grade B or API 5L Grade B for low pressure range and any of the API 5LX range for high working pressure or large diameter pipeline where a lower grade will require excessively thick walls to cope with the desired working pressures b) The line pipe shall be seamless in fabrication and be Electric Resistance Welded (ERW) or Double Submerged Arc Welded (DSAW) types only.
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c) The design shall generally be in accordance with the standard ANSI/ASME B 31.4 – 1979 and its subsequent revisions published by the American Society of Mechanical Engineers under the title ‘liquid Petroleum Transportation Systems” d) In addition to the general provisions of the code, special attention shall be paid to the following: i)
Wave and current loads shall be taken into account in the stress calculation of pipelines to be laid at sea or riverbeds without burial.
ii)
Calculation of limit stresses due to sustained load, thermal expansion and occasional loads where applicable shall be strictly in conformity with paragraphs 402.3.2 and 402.3.3 of the code.
iii)
Design and material selection of the pipeline c omponents such as tees, elbows, bends, valves, fittings etc. shall in all respects, conform to chapter II, part II and III of the code.
iv)
No used fitting of an existing pipeline shall be reused on a new pipeline without its original specification being identified and confirmed to be capable to perform the new service
v)
Threaded joints at both internal and external portions shall all be of the tapered line pipeline thread type conforming with API standard 5B or NPT threads in accordance with ANSI B2-1 while the least nominal wall thickness o f the threaded portion of the pipe shall not be less than the value specified in ANSI B.36.10
vi)
All threaded joints shall be on sections of the pipeline above ground.
vii)
If two or more pipelines are to be connected in manner that one will operate at a pressure higher than the other, they shall be so designed that the pipeline system operating at the lower pressure shall not be subjected to any pressure greater than its licensed operating pressure. 13
viii)
All pipe fittings, valves and equipment connected to the pipeline shall have manufacturers’ ratings which are equal to or greater than the proposed maximum operating pressure of the pipeline.
2.2.0
CONSTRUCTION PROCEDURE
2.2.1
Application: This procedure shall apply to new pipelines construction and replacements of existing pipelines.
2.2.2
Construction Code a) The licensee shall inform the Director of Department of Petroleum Resources prior to the start of construction. b) All metallic pipeline material to be buried shall be coated with any of the following systems – coal-tar enamel, Asphalt enamel, polyethylene tape, epoxy, asphalt mastic, urethane or other material specially approved by the Department of Petroleum Resources for specific reasons, while all surface pipelines shall be painted, raised and maintained above ground on permanent supports. c) The pipeline construction shall generally follow the steps outlined in Chapter V of the standard ANSI/ASME B 31.4-1979 or its subsequent revisions. d) All pipeline construction shall be carried out in a manner that will minimize disturbance to the environment. e) Special precautions shall be taken to protect the pipeline from washouts, unstable soil, landslides or any other hazards that may cause the pipeline to move or be subjected to abnormal loads. f) Ditching for the pipeline shall follow good pipeline practice and consideration for public safety as provided for in the Standard API RP 1102 shall be followed. g) All pipelines welding shall be in accordance with the provisions of API 1104/1107 while welding inspection shall be by non-destructive method preferably using Radiographic method contained in API 1104 – 1973 or its later editions. h) Minimum soil coverage of pipelines shall be as follows: Dry land – 1.0 meter. River crossings and riverbeds – 1 meter. Drainage ditches, Rail Road and Highway Crossing – 1.5 metres Rocky Areas – 0.9 metres 14
Swamp – 1.0 meter Shipping Channels – 2.0 metres i) At Rail road and Highway crossings, in addition to the specific requirement of the relevant Government Agency responsible for these infrastructures, the following precautions shall be taken: j) Installations of carrier pipe or casing shall be in ac cordance with API RP 1102. ii)
The casing shall be insulated from its carrier pipe support and shall extend to both sides of the railroad or highway. In the alternative the crossing could be of a thicker wall line pipe covered with compacted full and protective reinforced concrete slab.
iii)
All surface lines shall be similarly buried with casing protections or special construction specified in (ii) above at such crossings.
iv)
Pipeline warning signs shall be conspicuously displayed at both the entry and exit points of the pipeline crossings of railroads, highways, other pipelines and rivers.
k) The licensee shall identify any pipeline laying within 30 metres radius of its area of ground disturbance during pipeline construction. l) The licensee before commencing any ground disturbance in a populated or controlled area shall first accurately locate the position and alignment of the pipeline with markings and distinguishable warning signs at adequate intervals. m) If a pipeline lies within the 30-metre radius of co nstruction, the licensee shall endeavor to first of all locate the pipeline in question and manually excavate it till it is sufficiently exposed for purpose of identification and avoidance by the construction equipment. The same precaution shall be taken by any third party undertaking any construction activity within this radius of safety zone around any pipeline. Once the pipeline has been so exposed, no excavation within 1 meter radius of it, shall be allowed n) Where in the opinion of the Director of Department of Petroleum Resources, it is desirable to do so, it may direct that an existing pipeline located within the construction zone of a new pipeline in a populated or controlled area be either completely de-pressurized, operated at reduced pressure, or be otherwise protected throughout the period of ground disturbance in its vicinity.
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o) The same precautions as stipulated in (1) and (m) above shall apply to pipeline crossings. p) Mainline block valves shall be installed on the upstream side of major river crossings and at pump stations while check valves shall be installed downstream of river crossings. Also, mainline valves shall be installed at other sensitive locations of the pipeline such as in industrial, commercial and densely populated areas where construction activities may pose particular risks of damage to the pipeline. The pipeline right of way in these areas shall be clearly marked with signs for ease of identification. q) Six months after the completion of construction, the licensee shall submit two copies of the as built plan of the pipeline on the same scale as that of the plan submitted along with the pipeline licence.
2.3.0
PROCEDURE FOR INSPECTION AND TESTING.
2.3.1 Notification: The Licensee shall notify the Director of Department of Petroleum
Resources of the completion of construction of the pipeline or any sections of it which is due for testing giving notice of not less that one month from the date of commencement of such tests. 2.3.2
Inspection and Test Guidelines a) The pipeline material and construction shall be inspected visually and examined radio graphically according to the procedure enumerated in Chapter VI of the reference standard ANSI/ASME B 31.4 – 1979 or its latest edition b) All tests shall generally be hydrostatic and be conducted in a manner that will ensure the protection of life, property and the general environment of the pipeline. c) The entire length of the pipeline shall be tested to the designed rated pressure while any in-line pressure vessel or pre-fabricated manifold on the pipeline shall be tested to the manufacturer’s specifications in accordance with the Mineral Oils Safety regulations (MOSR). d) The pressure recording instruments to be used for the tests shall have a valid calibration certificate which should not be more than a year of issue and the chart 16
record of the test shall be continuous and legible and all test results and any remedial action taken shall be submitted to the Director of Department for approval before commissioning of the pipeline. The Accuracy of the pressure recorder shall be within two per-cent (2%) of its range. e) Unless otherwise permitted by the Director of Department of Petroleum Resources, pressure test duration shall not be less than twenty-four hours of continuous test both for leaks and material failures. Buried pipeline of u p to 100 meters in length and all surface running pipelines could be tested for less periods but not lower than (1) hour. f) The general guiding rule for environmental protection shall be as follows: (i) Where the test pressure shall result in a hoop stress greater than 75 percent of specified minimum yield strength of the pipeline based on the nominal wall thickness, and the pipeline does not cross or pass within 100 metres of any environmental protection arrangement, otherwise permission of the Director of Department of Petroleum Resources would be required to ensure that adequate contingency plans have been made for protecting the environment. (ii) Any pipeline crossing watercourses shall be tested with adequate environmental precautions taken. 2.3.3
Test Code
a) Unless otherwise authorized by the Director of Department of Petroleum Resources, the following shall generally apply: i) The actual test pressure throughout the duration of test shall not exceed 110% of the minimum yield strength of the pipe material; hence the testing equipment shall be preset not to produce more than this pressure during the test. ii) The test medium shall be water except with special permission of the Director of Petroleum Resources. b) All buried pipelines shall be tested to a pressure not less than 1.25 times the maximum designed operating pressure. c) Surface pipeline transmitting liquid petroleum or gas shall be tested up to a pressure not less than 1.4 times the maximum designed operating pressure. d) All pipelines shall be tested to a minimum pressure of not less than 700 kilopascals unless otherwise permitted by the Director of Department of Petroleum Resources
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e) The maximum test pressure in all cases shall not result in a hoop stress, greater than 110 percent of the specified minimum yield strength of the pipe material based on its nominal wall thickness. f) Valves and fittings on the pipeline under test shall not be subjected to a pressure greater than the manufacturer’s test pressure rating during the test.
2.4.0
SAFETY AND MAINTANANCE PROCEDURE
2.4.1
The operator shall establish a written emergency plan for implementation in the event of systems failures, accidents and other emergencies, which shall include procedures for prompt and expedient remedial action for the following. i)
Safety of the public and operator’s personnel
ii)
Protecting of property and the environmental and control of accident discharge from the pipeline
iii) 2.4.2
Adequate Personnel training for handling such emergencies
Care shall be taken to ensure that at no time should the maximum steady state operating pressure and static condition exceed either the internal design pressure or the pressure ratings of components used whichever is less. Pressure surges or any momentary pressure variations shall not exceed 10 percent of these pressure limits.
2.4.3
Pipeline markers at crossings shall indicate the location of the line and the name of the operating company.
2.4.4
All pressure relief devices shall be activated after installation to ensure that they function properly and shall be inspected and re-certified once in twenty-four (24) months with the report of such tests lodged with the nearest office of the Department of Petroleum Resources.
2.4.5
The right of way should be maintained so as to have a clear visibility and give reasonable access to maintenance crews. Clear access shall be maintained to valve locations and ditches shall be protected against washout of the line.
2.4.6
The right of way shall be regularly patrolled for prompt detection of any line break, encroachment or any other development that may endanger the safety of the pipeline and any such development shall be promptly reported to the nearest office of the Department of Petroleum Resources.
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2.4.7
All under water crossing shall be periodically inspected but not longer than once in two years to ensure that there is sufficient cover for the pipeline and that the safety of the line at crossings is not endangered in any way.
2.4.8
All pipeline repairs shall be carried out in accordance with good pipeline practice and shall be generally undertaken in accordance with the safety provisions contained in the API RP 1107 and API RP 1111 standards. The repaired section of the pipeline shall be pressure tested at expected operating conditions like a new line. Detail report of this exercise shall be submitted to the Director, Department of Petroleum Resources.
2.4.9
For offshore pipelines connected to platform risers, the riser installations shall be visually inspected annually for physical damage or corrosion in the splash zone and above. Records of such inspections shall be kept on site for future verifications whenever the need arises.
2.5.0
CORROSION CONTROL
The following shall constitute the minimum requirements and the procedure for cathodic protection of ferrous pipe and its components from internal and external corrosion the design of which shall generally follow the specifications and procedures prescribed in NACE RP 0169-96. and section 10.1&10.2 of API RP 1160 managing pipeline system integrity. 2.5.1
External Corrosion Control of Buried or Submerged Pipeline This shall consist of application of coating to the pipeline and its cathodic protection to achieve the following objectives: a) Protective Coating i) Shall be applied in such a way that it will mitigate corrosion and adhere to the pipe metal surface sufficiently enough such that it will effectively resist under film migration. ii) Shall be ductile and strong enough to resists cracking and damage during handling and under soil stress. iii) Shall be compatible with any supplemental cathodic protection and if is an insulating type material shall have low moisture absorption. iv) Shall be applied in such a way that no irregularities protrude through it and no holiday gaps exist in the coating all along the whole length of the pipeline.
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v) The points of connection of any attachment to pipeline shall be equally sealed with the coating, together with the attachments themselves. b) Cathodic Protection System i) This shall be provided by either a galvanic anode or impressed current anode system installed in such a way that it mitigates corrosion and contains method of determining the degree of cathodic protection achieved on the pipeline. The criteria for the selection of an appropriate protection system shall be as listed in section 7 paragraph 7.5 of NACE standard RPO 169-96 and relevant subsequent provision. ii)
The system shall be installed not later than one year after the laying of the pipeline in such a way that the pipe coating at the points of installation are kept
iii)
The cathodic protection system shall be electrically isolated at all interconnections to other pipeline systems or structures except where the two structures are mutually protected by the same system.
iv)
The cathodic system shall be protected against damage by atmospheric electrical discharges, underground cables and power lines.
v)
Except for underwater pipelines, sufficient test leads shall be installed on b uried pipelines for occasional check of the effectiveness of the cathodic protection to be carried out by electrical measurements. Such test stations shall include all pipe casing installations, insulating joints, all crossings and main manifold junctions.
vi)
A minimum separation of 3 meters shall be maintained between electric transmission tower footings, ground cables and earthlings, power lines and the pipelines under protection.
c)
Monitoring of Cathodic Protection Systems
i)
Cathodic protection facilities shall always be maintained in serviceable condition and be electrically tested and inspected once a year with appropriate corrective measures taken where such inspections reveal any weakness in the system. A report of such inspections shall be lodged with the Department at the completion of such exercise. However, all sources of impressed current rectifiers and other associated devices shall be inspected and tested at quarterly intervals to ensure that they are functioning properly.
2.5.2
Internal Corrosion Control
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a) The general rule shall be that of avoiding transportation of any corrosive materials in a pipeline without appropriate measure taken to mitigate the corrosion effect of the commodity on the internal section of the pipeline. b) However, internal corrosion shall be prevented either by frequent pigging, inhibiting, scraping or application of internal coating o n the pipeline before laying. c) Whichever method is used, appropriate precautions shall be taken, such as the utilization of sufficient coupon holders when inhibitors are used and the compliance with established industry standards of internal coating materials.
2.5.2.1 Monitoring of Internal Corrosion This shall be by the running of intelligent pig or other internal pipeline survey instrument throughout the whole length of the pipeline at least once in five years. A report of such annual inspection shall be lodged with the Department on schedule.
2.6
RISK BASED INSPECTION
2.6.1 Licensees shall submit in duplicate copies details of its risk based inspection programs for review and endorsement. Program shall as a minimum specify the following: 1.
The overall principles upon which the RBI program is designed
2.
The approved Risk Assessment methods utilized for RBI program
3.
An overview of the proposed plan for addressing all the identified risk to ALARP levels
4. An overview of performance monitoring methodology of the proposed plan for risk mitigation 5. An RBI Emergency response plan 6. An overview of the Database program required for the RBI program. It shall be expected that elements that define availability and reliability for a robust database program will be furnished. 7. An overview of the implementation program vis-à-vis human resource responsibility levels for RBI execution 2.6.2
RBI programs shall be reviewed on an annual basis with representatives of the Director of Petroleum Resources, at such a period when all performance indicators for a licensees’ RBI programs for all its pipeline systems are ready. To this effect, it is required that licensee notifies the Department at least a month in advance. 21
2.6.3
The Department shall be notified of all baseline inspection activities for generation of RBI performance indicators and provision made for its ac tive participation.
2.6.4
Licensee shall ensure that the Department is availed reasonable opportunity of training relevant to all the areas of its RBI program.
SECTION III GAS TRANSMISSION AND DISTRIBUTION PIPELINE 3.1.0
GENERAL DESIGN CONSIDERATIONS
3.1.1
Scope: The guideline covers the design, fabrication, installation, inspection, testing, operation and maintenance of gas transmission and distribution systems. It shall apply to piping systems required to operate with metal temperature of between 450oF and minus 20oF only.
3.1.2
Design Criteria and Materials Specifications Applicable standard shall be the ANSI/ASME B31-8 1986 or its later editions under the title “Gas Transmission and Distribution Piping Systems”
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a) All materials to be used shall generally conform to the specifications in appendix B of the reference Standard ASME B31.8 for the structural materials of the line pipe, valves, fittings and flanges, bolting and tubing. b) The pipelines shall be generally seamless or of the ERW and SCAW types. c) Thermoplastic and thermosetting pipe materials shall also be acceptable provided that they conform to ASTM specifications 02513 and 02517 respectively and shall be inhibited against material degradation effects of ultra violet rays if used in locations where the pipeline is exposed to sunlight. d) Weldability of the ferrous pipe material shall be tested in accordance with the requirements of API standard 1104. e) Adequate provision shall be made for the flexibility of the pipeline while under pressure in the form of anchorage and guide points and for temperature induced stresses by allowing for expansion joint couplings. 3.2.0
Guideline for the Design, Construction and Inspection Testing of Gas Pipeline
3.2.1
Application These guidelines shall apply to the design and construction of new pipelines and the replacement of existing ones as from the date of adoption of this document.
3.2.2
Applicable Standards and Specifications a) The standards and codes specified in ANSI/ASME B31.8 and National Association of Corrosion Engineers Standards RPO169-96 generally referred to as NACE standard RPO169-96 shall be followed in the design and construction of gas pipelines and their corresponding corrosion control installation respectively. b) The process of manufacture of the specified pipeline system shall generally comply with the various specifications of API 5L or its internationally recognised equivalent. It shall be expected that operator or owner of a licensed
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pipeline system shall maintain in its custody sufficient manufacturing records and data to substantiate that acceptable industry standard was employed in the production of the pipeline system. Manufacturing records such as incoming material inspection reports, welding procedure specification / procedure qualification records, in-factory mechanical and che mical tests records as well as NDTs results, calibration data or certification of test equipments, approved ITPs and marking schemes, material traceability, dimensional checks and report of workmanship/defects examinations carried out during manufacturing processes etc. c) Long distance gas transmission pipelines shall be made of steel, the design and construction of which shall be governed by the population density indices specified in ANSI/ASME B31.8 and the corresponding design factors. Also the specified construction types of pipelines in the proximity of main roads and railroads and the mode of their crossing shall be complied with. d) The minimum depth of burial shall be as specified in section II paragraph 2.2.2 (h) but where these minimum depths could not be achieved or the pipeline at these points shall be encased, bridged or specially reinforced to withstand any anticipated external load. e) There shall be a minimum clearance of 0.5 meter between the pipeline and any other underground structure not connected with it. f) It shall be mandatory for all buried pipelines to be protected against corrosion and where any pipeline is to transport corrosive or toxic gas, then the design parameter shall be such that the gas pressure at any time in the pipeline shall not result in a hoop stress greater than 60 percent of the specified minimum yield strength of the pipeline material based on the nominal wall thickness. Also, block valves and check valves for such pipelines shall be so located as to prevent the escape of the corrosive or toxic gas into the atmosphere in the event of a pipeline failure.
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g) Inspection of pipeline construction materials and its appurtenances, welding, ditching, stringing and the general installation shall follow the procedure outlined in chapter IV of the ANSI/ASME B31.8. h) All gas pipelines laid in farmlands, virgin areas and sparingly populated areas shall be tested with water up to a minimum pressure of 125 percent of their maximum operating pressure or with air up to 110 percent of their minimum operating pressures. Pipelines laid in densely populated areas shall be tested ONLY with water up to a minimum and the test result shall be lodged with the nearest office of the Department of Petroleum Resources in the area. i) Leak test shall however be performed on the pipeline system with the use of pressurized air or gas between 100 PSI to 20 percent of the minimum specified yield of the material for pipelines that has been designed to withstand 20 percent or more of the specified minimum yield strength. While pipeline to operate at below 100 PSI be leak tested at maximum system pressure.
3.2.3
Design Specifications of Gas Pipeline Ancillary Equipments / Facilities
3.2.3.1 Regulating & Metering Stations The following design specifications shall be applicable to PRMS associated with gas pipeline systems. a) design factor of station piping shall be 0.50 b) All gas flow rate, totals and quantities delivered during any period shall be calculated by the operator in accordance with best proven industry standard.
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c) Calculated volumes shall be corrected for temperature and density as provided in ISO 9676 at base conditions of 14.73psia (1.01560 bar) and 60 deg F (15.5 deg C). Corrections of volumes for deviation from Boyle’s Law shall be made in accordance with the procedures published in the AGA report No.8. d) The accuracy of all measuring instruments shall be validated by the operator at-least once in every calendar month and the period between any two re-validation of any such equipment shall not exceed 60 days. Re-calibration of equipments shall done a t-least once in every 12 months. Validation and calibration procedures shall be established during the procurement of such equipment. e) The operator shall ensure that data used to determine invoiced quantities will be retained for a period of 24 months from the end of the calendar year to which they relate (unless there is a dispute, in which case such records shall be retained until the resolution of the dispute) f) The operator shall inspect each valve critical to the safe operation of the pipeline and shall carry out a partial stroke test at intervals not ex ceeding 15 months, but at-least once each calendar year. The operator shall maintain valves in accordance with valve manufacturer’s recommendations. g) The operator shall not discharge gas from Blow-down piping where it will create a hazard to public health or safety.
3.2.4
Gas Pipelines made with materials other than Ductile steel
a)
Cast Iron Materials Cast iron Materials shall be used for gas pipelines under specified application to and special approval by the Director, Petroleum Resources and all such applications shall be supported with the compelling reasons for using Cast Iron Material. In such the design considerations shall strictly follow the specifications in paragraph 842 of the reference standard.
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b) Plastic Materials: The use of thermoplastic and thermosetting plastic materials of the grades specified in ASTMD 2513 and ASTMD 2517 shall be generally allowed for laying service lines only. a. The design pressure for plastic gas piping system shall be governed by the formula given in paragraph 824.31 of reference standard (ANSI/ASME B31.8) where the value of the plastic design factor shall not be less than 0.32 for any case. ii)
Plastic pipe materials shall not be used in any service where the maximum and minimum operating Temperatures shall be higher or lower than 100oF and 20oF respectively
iii)
Plastic pipe materials to be used shall be inhibited against the effect of Ultraviolet rays which renders such materials brittle when exposed to sun light
iv)
Plastic pipes or tubing shall not be threaded at joints but shall be jointed by the solvent cement method, adhesive method, and heat-fusion or by the means of compression coupling or flanging whichever conforms to the manufacturer’s specifications.
v)
Extreme caution shall be taken in laying plastic pipelines to avoid any damages to the material. All buried plastic pipelines of ½ inch nominal diameter and above shall have a minimum wall thickness of 0.1 inch while those below ½ inch nominal diameter shall have a wall thickness not less than 0.06 inch.
vi)
Plastic pipes shall be buried in undisturbed or well-compacted soil while no mitre bends shall be permitted at any portion of the pipeline.
vii)
Plastic pipes shall be tested at pressure not less than 150 percent of their maximum operating pressure or 50 PSI whichever is greater and shall not on any occasion be subjected to a pressure more than 300 percent of their maximum operating pressure.
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viii)
Certificate of conformity to required specifications shall amongst other items provide information on the following parameters for plastic gas transmission system : Compound Conventional density Volatile content Water content Carbon Black dispersion Resistance to gas condensate Resistance to Rapid crack propagation (critical pressure, Pc) (e>/= 15mm) Resistance to slow crack growth (dn: 110mm or 125mm- SDR 11) Tensile strength for butt fusion (dn:110mm or 125mm- SDR 11) Pipeline Hydrostatic strength (20 deg centigrade, 100h, 80 deg c, 165h, 80 deg c,1000h) Elongation at break Resistance to slow crack growth e 5mm (Notch test) Resistance to rapid crack propagation (critical pressure, Pc) Oxidation induction time (Thermal stability) Melt mass flow-rate (MFR) Longitudinal reversion Valves Resistance to weathering Leak-tightness of seat and packing Actuation mechanism resistance Resistance to bending between supports Thermal cycling resistance dn>63mm Leak-tightness under bending with thermal cycling, dn
3.3.0
OPERATION AND MAINTENANCE OF GAS PIPELINES.
3.3.1
This shall be as specified in paragraph 2.4.0 and 2.5.0 of section II of this document in addition to which the provisions of NACE standard RP1069-96 shall be followed in the design and maintenance for the associated corrosion control system of the pipeline.
3.3.2
Any gas pipeline that will not be put into use for more than six months after construction shall be filled with inert gas or nitrogen and if it is to be put into use after one year of
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completion shall be pressure tested and certified by an official of Department of Petroleum Resources before being put into use. 3.3.3
Gas pipeline systems shall be well purged with water, air or inert gas before undertaking any repairs and the environment of the repair site shall be constantly monitored with gas detecting device to ensure adequate safety.
SECTION IV PROCEDURE FOR UPGRADING OF A PIPELINE OR FOR CHANGING THE SUBSTANCE TRANSMITTED BY THE PIPELINE
4.1.0
PIPELINE UPGRADE.
4.1.I
Application
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Any Licensee that desire to upgrade the maximum operating pressure of this pipeline shall lodge an application with the Department of Petroleum Resources to that effect giving the following information: a) The reason for his desire to operate the system at a lower/higher pressure than its original maximum designed pressure. b) The leak/repair history of the pipeline to be upgraded. c) The modification that shall be made to the pipeline system to qualify it for upgrading in accordance with the specifications contained in paragraph 845 of ANSI/ASME 31.8 d) The test that will be carried out on the pipeline system after upgrading which shall be compatible with the procedure outlined in section III paragraph 3.2.0 of this documents in which the upgrade maximum operating pressure will now be pressure parameter to use for the tests. 4.1.2
The grant of approval to carryout the upgrading and operate the upgrade pipeline at the new pressure shall be contingent upon satisfactory fulfilment of the conditions listed in 4.1.1 above.
4.2.0
CHANGING OF THE SUBSTANCE TRANSMITTED BY THE PIPELINE
4.2.1
Application
This shall apply to situations when the Licenses desire to change the nature of the fluid transmitted by the pipeline in the following manner:
4.2.2
a)
From Liquid Petroleum to Gas
b)
From sweet Gas to Corrosive Gas
c)
From Hydrocarbon substance to water etc.
Procedure
In all such cases, an application for making the change shall be made to the Director of Department of Petroleum Resources giving the following information. a)
The reason for the change
b)
The leak history of the pipeline in question
c)
The modifications that shall be made to the pipeline system for it to be capable of rendering the new service.
d)
Other relevant information that will enable the Department undertakes a realistic assessment of the request for the purpose of approval. 30
4.2.3
Emergency Notice. In case of an emergency, the nearest office of the DPR shall be notified of the above (4.2.0)
SECTION V PROCEDURE FOR DISCONTINUATION, ABANDONMENT AND RESUMPTION OF OPERATION OF PIPELINE SYSTEMS
5.1.1
Discontinuation of Operation of Pipeline Systems
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a) The Licensee shall apply to the Department giving three months notice of its intention to discontinue with the operation of the pipeline system or ancillary facilities such applications shall be accompanied with the following i)
The reasons for the discontinuation of the operation of the pipeline system
ii)
Two copies of the plan of the entire pipeline or part there of in which the operations is to be discontinued shown in green colour.
iii) 5.1.2
The proposed method of discontinuing operations.
Procedure for Discontinuation of operations
a) Apart from the conditions that may be specified when granting discontinuation approval, the pipeline to be discontinued with shall be disconnected from all other facilities like other pipelines, meter stations, ancillary facilities and other appurtenances. b) It shall be purged of all Petroleum Liquid or Gas with water or an inert material and capped at both ends with moisture resistant materials.
5.2.0
Abandonment and Removal of Pipelines
5.2.1
All the steps outlined in 5.1.1 and 5.1.2 above shall be followed in cases where the pipeline is to be completely abandoned.
5.2.2
The right of way of abandoned pipelines shall continue to be maintained and clearly identified for as long as the pipeline remains in place.
5.2.3
In cases where the pipeline is to be removed, the Licensee shall furnish the Department with the proposed work programme for its removal. Also the Licensee shall restore into perfect condition the right of way of the pipeline and other disturbed land areas in the neighbourhood after its removal.
5.3.0
Resumption of Operation of an Abandoned or Discontinued Pipeline
5.3.1
An application shall be made to the Department for approval to resume ope rations in an idle pipeline system.
5.3.2
Such applicants shall state reasons for the resumption of operation and the proposed method to be used in reactivating the pipeline.
5.3.3
All such pipelines shall be tested as new under the proposed operating conditions of the pipeline after reactivation.
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SECTION VI FLOW-LINE, PIPELINE & RISER SYSTEMS FOR OFFSHORE OPERATIONS 6.1 Basic Statutory Approvals
Basic statutory pipeline approvals applicable to deep offshore flow-line, pipelines and riser systems shall as a minimum be as given in section I.
6.2 Design Criteria
In addition to the general requirements of sections II & III of this guideline the following shall be specifically applicable to the design of any Flow-line and riser system in the Nigerian offshore and deep offshore locations: Proper design consideration shall be given to establish acceptable / tolerable limits for the following parameters associated with offshore flow-lines and riser operations: 6.2.1 Allowable stresses 6.2.2 Allowable deflections 6.2.3 Hydrostatic collapse 6.2.4 Fatigue / Service Life 6.2.5 Overall column Buckling 6.2.6 Storm and contingency operation 6.2.7 Loads and load effect 6.2.8 Loading conditions 6.2.9 Flow-assurance 6.2.10 Maintenance, Inspection and replacement 6.2.11 Temperature limits 6.2.12 Abrasion and wear 6.2.13 Interference 6.2.14 Corrosion 6.2.15 Marine Growth and Biological Considerations 6.2.16 In-place Stability API 2RD & API 1111 shall form the basic reference codes / standards for the design of these systems.
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Where model studies will be carried out for any of the systems associated with the FLRs, for the purpose of guaranteeing any design / technological procedure the company shall notify the Director of Petroleum Resources at-least four (4) weeks prior to the co nduct of the exercise. The Director shall have the liberty of nominating officers to witness and endorse the results generated in such model test activity.
6.3 O&M
The approved operation and maintenance schedules shall be appropriately implemented during the operational life span of the FLR systems. Failure to fully implement the approved O&M programs shall become an offence punishable under the prescribed penalties of the Oil pipeline acts of the Federal Republic of Nigeria.
SECTION VII OPEN ACCESS PIPELINE SYSTEMS
Open access pipeline systems shall comply with all the statutory requirements of this procedure guide and additional requirements specified by applicable open access regulatory frameworks.
SECTION VIII MISCELLANEOUS 8.1 ACCIDENT REPORTING FORMAT
All accidents related to any pipeline operation shall be reported within 48 hrs of its discovery to the closest office of the Department of Petroleum Resources giving the following information: i. Pipeline system affected ii. Valid OPLL number iii. Suspected cause of accident 34
iv Estimated lost associated with the accident v Emergency remediation response effected on discovery vi. Plan for restoration of pipeline operations to its licensed conditions
8.2 NON-COMPLIANCE WITH THE PROVISIONS OF THIS GUIDELINE
Non-compliance with the provisions of this guideline by any pipeline operator / owner shall be treated as an offence punishable under the penalties prescribed under the Oil pipeline act or the special fines approved by the Director, Department of Petroleum of Resources for the purposes of enhancing strict compliance with relevant pipeline legislation.
8.3 VARIATION
Any required variation from the provisions of this guideline shall be communicated to the Director, Petroleum Resources before implementation.
The Director, Petroleum Resources, shall grant approval for such variation to be implemented and where such an approval can not be granted, the company shall be duly informed.
8.4 PIPELINE COMMUNITY ENGAGEMENT
Every pipeline development activity shall be expected to develop a sustainable Community Engagement Program (CEP) for all its pipeline communities.
The CEP shall optimally involve all necessary stakeholders in both its generation and implementation and shall be submitted in three (3) copies for the approval of the Department of Petroleum Resources along with the request for grant of Oil Pipeline License.
As part of the community engagement program, company shall consider incorporating the following:
1. Pipeline community shall supply manpower requ ired for conducting an effective R.O.W surveillance coordinated by the community head. Surveillance activity shall be conducted under an MOU executed between the pipeline owner and the community leader spelling out responsibilities, allowances and reporting pattern.
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2. Pipeline owner shall optimally utilize pipeline community local content capacity in executing all pipeline related projects.
3. State government shall endorse the CEP that is to be submitted to the Department of Petroleum Resources.
Renewal of existing pipeline systems shall be granted only on the submission and approval of a comprehensive pipeline CEP.
DEFINITIONS APPROVAL – Formal grant of consent by the Director of Petroleum Resources in any
retrievable format that can be re-produced as documentary evidence.
CONCEPTUAL DESIGN – Engineering design activities required to specify pipeline
development programs such as SOW, BFD, technical specifications etc. Conceptual Design Approval shall be granted for stand-alone pipeline development projects while approval for facility development project with major pipelines being part of the SOW shall be granted only after an endorsement of pipeline concept by pipeline and Oil transportation.
COMMISSIONING – Series of activities leading to the introduction of hydrocarbon fluid into a
pipeline system that has been successfully pre-commissioned. Commissioning approval shall be obtained prior to commen cement of scheduled activities and procedures connected to commissioning.
CEP- Community engagement program
DETAILED DESIGN- Engineering activities required to develop an approved conceptual
design into an executable level for provision of a pipeline system. Detailed design approval shall be granted for stand-alone pipeline development projects while approval for facility development projects with major pipelines being part of the SOW shall be granted only after an endorsement
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of the pipeline detailed design activity by Pipeline and Oil Transportation branch of the Department.
DIRECTOR- The Director of the Department of Petroleum Resources or an appointed officer
by the Director to act on his behalf.
EMERGENCY SITUATION- An event and /or operational offset, that requires an immediate
remedial action and /or solution of that nature or extent that can be termed mandatory for a safe operation of the pipeline system.
EXCEPTION- These are areas where the normal requirements of these guideline are not
applicable in either its entirety or otherwise.
EXPOSED PIPELINE – A pipeline where the top of the pipe is protruding above ground for
onshore / swamp pipelines and or where the top of the pipe is protruding above the seabed in water less than 8 meters deep as measured from the mean low water mark for offshore pipelines.
FLOWLINE- A pipeline flowing hydrocarbon and /or their derivatives or components from the
wellhead facilities to the first gathering manifold.
FLR – Flow-line and Riser
MAINTENANCE – Approved programs or plans of condition monitoring and repairs required
to ensure that pipeline system operates optimally for the required life-span.
MFR- Melt mass Flow-rate for pipeline plastic material
MIP – Manufacturing Inspection plan and is required during project implementation to ascertain
the technical integrity of line pipes, coating and all other associated components of the pipeline system.
OFFENCE- A breach of this guideline or any requirements associated with compliance to the
Oil pipeline act. 37
OPEN ACCESS – Pipeline system operated within the open access regime.
OPERATION- The normal execution of activities for which pipeline system was designed to
perform.
PIPELINE- A pipe or tubing used in the transportation of hydrocarbon resource from the first
gathering manifold to all the facilities required for processing, distribution and export.
PIPELINE SYSTEM- All parts of those physical facilities comprising a particular pipeline
through which hydrocarbon resource flows, including pipe, valves, and other appurtenances attached to pipe such as, pump or compressor stations, regulating and metering stations, block valve stations, electrical equipment stations for CP etc.
PIPELINE GAS – Gaseous Petroleum shall include but not limited to the product specification
of export gas in GPSA and ASME B 31.8.
PIPELINE LIQUID - Liquid Petroleum shall include but not limited to the scope of fluids
covered by ASME B 31.4
PRE-COMMISSIONING – Series of approved activities required for the purpose of
establishing availability, functionality and reliability of a pipeline system prior to introducing hydrocarbon for normal transportation services. Pre-commissioning schedules and procedures shall be submitted to the Director of Petroleum Resources before commencement of such activities.
PROJECT- Activities executed within a framework that requires approvals / endorsements.
RE-VALIDATION- Processes of confirming validity of any statutory instrument that has been
granted in situations where a modification of the original approval criteria is a possibility or equipment used in monitoring / controlling the hydraulic properties of pipeline flow.
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