CHEVRON RESEARCH AND TECHNOLOGY COMPANY
RICHMOND, CA
November 1994
Manual sponsor: For information or help regarding this manual, contact T. (Tim) Sheckler (510) 242-2298
Pipeline Manual
First Edition November 1989
First Revision January 1990
Second Revision January 1991
Third Revision May 1993
Fourth Revision November 1994
The information in this Manual has been jointly developed by Chevron Corporation and its Operating Companies. The Manual has been written to assist Chevron personnel in their work; as such, it may be interpreted and used as seen fit by operating management.
Copyright 1988, 1990, 1991, 1993, 1994 CHEVRON CORPORATION. All rights reserved. This docu-ment contains proprietary information for use by Chevron Corporation, its subsidiaries, and affiliates. All other uses require written permission.
Restricted Material
Technical Memorandum
This material is transmitted subject to the Export Control Laws of the United States Department of Commerce for technical data. Furthermore, you hereby assure us that the material transmitted herewith shall not be exported or re-exported by you in violation of these export controls.
Pipeline Manual
The following list shows publication or revision dates for the contents of this manual. To verify that your manual contains current material, check the sections in question with the list below. If your copy is not current, contact the Technical Standards Team, Chevron Research and Technology Company, Richmond, CA (510) 242-7241.
Section Date
Front Matter November 1994
Table of Contents November 1994
References November 1994 Section 50 November 1994 Section 100 November 1988 Section 200 November 1988 Section 300 November 1994 Section 400 November 1994 Section 500 November 1988 Section 600 November 1988 Section 700 November 1994 Section 800 November 1988 Section 900 November 1994 Section 1000 May 1993 Section 2000 November 1994 Company Specifications PPL-MS-1050-H May 1993 PPL-MS-1564-D January 1990 PPL-MS-1632-E November 1988 PPL-MS-1800-G November 1990 PPL-MS-4041-B May 1993 PPL-MS-4737-A November 1994 PPL-MS-4807 January 1990 Data Sheets PPL-DS-4737 November 1994 PPL-DS-1050 May 1993
PPL-DS-4807 January 1990
All other Data Sheets November 1988
Data Sheet Guides
PPL-DG-1050 November 1994
PPL-DG-4041 November 1994
PPL-DG-4807 January 1990
All other Data Sheet Guides November 1988
Standard Drawings and Forms All specifications, drawings, and forms are marked with thier latest revision dates.
GE-L99880 November 1988 Appendix A November 1988 Appendix B November 1988 Appendix C November 1988 Appendix D November 1988 Appendix E November 1988 Appendix F November 1988 Appendix G November 1988 Appendix H January 1990 Appendix I November 1994 1 PC Disk November 1994
Pipeline Manual
If you have moved or you want to change the distribution of this manual, use the form below. Once you have completed the information, fold, staple, and send by company mail. You can also FAX your change to (510) 242-2157.
❑ Change addressee as shown below. ❑ Replace manual owner with name below. ❑ Remove the name shown below.
Send this completed form to: Document Control, Room 50-4328
Chevron Research and Technology Company 100 Chevron Way (P.O. Box 1627)
Richmond, CA 94802
CRTC Consultants Card
The Chevron Research and Technology Company (CRTC) is a full-service, in-house engineering organi-zation.
CRTC periodically publishes a Consultants Card listing primary contacts in the CRTC specialty divi-sions. To order a Consultants Card, contact Ken Wasilchin of the CRTC Technical Standards Team at (510) 242-7241, or email him at “KWAS.”
Previous
Owner: Title:
Last First M.I.
Current
Owner: Title:
Last First M.I.
Company: Dept/Div:
Street: P.O. Box:
City: State: Zip:
Pipeline Manual
We are very interested in comments and suggestions for improving this manual and keeping it up to date. Please use this form to suggest changes; notify us of errors or inaccuracies; provide information that reflects changing technology; or submit material (drawings, specifications, procedures, etc.) that should be considered for inclusion.
Feel free to include photocopies of page(s) you have comments about. All suggestions will be reviewed as part of the update cycle for the next revision of this manual.
Send your comments to: Document Control, Room 50-4328
Chevron Research and Technology Company 100 Chevron Way (P.O.Box 1627)
Richmond, CA 94802
Page or Section Number Comments
Name Address
This document contains extensive hyperlinks to figures and cross-referenced sections. The pointer will change to a pointing finger when positioned over text which contains a link.
Manual Sponsor: G. B. Kohut / (510) 242-3245 / E-mail: [email protected]
List of Current Pages
50 Using This Manual 50-1 100 General Information 100-1 200 Route Selection 200-1 300 Pipe and Coatings 300-1 400 Design 400-1 500 SCADA Systems 500-1 600 Construction 600-1 700 Inspection and Testing 700-1 800 Operations and Maintenance 800-1 900 Offshore 900-1 1000 Guidelines for Low Pressure Buried Fiberglass Pipe 1000-1 Appendices
Appendix A Conversion Tables Appendix B Directional Drilling Appendix C Offshore Pipelines
Appendix D Operating Plan Guidelines Appendix E Field Inspection Guidelines
Appendix F Development of Depth of Burial Diagrams Appendix G Subsea Valves
Appendix H Guidelines for Weight-Coating on Submerged Pipelines
Appendix I Calculation of Bending Stress in Buried Pressurized Pipeline Due to External Loads
Abstract
This section tells you how this manual is organized. A Quick-Reference Guide (Figure 50-1) is provided to highlight key areas of the manual. A cross-reference chart (Figure 50-2) relates the manual to others in the set.
Scope and Application
The Pipeline Manual, written for convenient reference by Company personnel engaged in technical work on pipelines, is directed to technical personnel regardless of experience. This manual should never substitute for sound engineering
judg-ment.
This manual contains guidelines and specifications for use by Company personnel. The material may be used as is, or modified for local organizational or geographic preferences, priorities, or experiences.
The intent is to provide practical, useful information based on Company experi-ence. Therefore, forms have been included in the front of the manual for your convenience in suggesting changes. Your input and experience are important for improving subsequent printings and keeping this manual up-to-date.
Organization
The Pipeline Manual is part of a set of manuals produced by Chevron Research & Technology Company in cooperation with all Operating Companies in the Corpora-tion. Several of these manuals contain information directly related to pipelines. • Piping
• Insulation and Refractories • Fluid Flow
• Instrumentation and Control • Coatings Corrosion Prevention
• Welding
All the manuals are interrelated; therefore, a list of cross references (at the end of this section.) has been developed to assist you in finding related subject matter. The index also aids in locating information in other manuals.
Each manual is organized using different-colored tabs to assist users in finding the appropriate information quickly:
• White tabs are for table of contents, introduction, appendices, PC disks, index
and general purpose topics.
• Blue tabs denote Engineering Guidelines.
• Gray tabs denote Specifications, Data Sheets, Data Sheet Guides, and related
industry standards (API, ANSI).
• A Red tab marks a place for you to keep documents developed by your organi-zation.
Part I - Engineering Guidelines
This part of the manual contains: (1) material selection guidelines; (2) design princi-ples and Corporation suggested practices; (3) construction techniques; (4) inspec-tion criteria; (5) operainspec-tional informainspec-tion.
Part II - Specifications
This part of the manual contains: (1) general instructions for using specifications; (2) model specifications, data sheets, and data sheet instructions that can be copied or modified to local preferences; and, (3) industry standards (API, ANSI).
Change Bars, vertical black lines, have been used in the margins of the master speci-fications to indicate where information has been added, changed, or deleted in refer-ence to the last edition of the manual.
Other Company Manuals
The text sometimes refers to documents in other Company manuals. These docu-ments carry the prefix of that manual. The prefixes are defined here:
Prefix Company Manual
CIV Civil and Structural
CMP Compressor
COM Coatings
CPM Corrosion Prevention
DRI Driver
ELC Electrical
EXH Exchangers and Cooling Towers
FFM Fluid Flow
FPM Fire Protection Manual
HTR Fired Heaters and Waste Heat Recovery ICM Instrumentation and Control
IRM Insulation and Refractory MAC General Machinery
NCM Noise Control PIM Piping PMP Pump PPL Pipeline PVM Pressure Vessel TAM Tank UTL Utilities WEM Welding
Fig. 50-1 Quick Reference Guide
Task Pipeline Manual Sections
Learn background information
• Hydraulics 400
• Design 200, 300, 400, 500, 600, 900 • Offshore 900
Specifying and purchasing
• Line pipe 300, 2000 • Induction bends 300, 2000 • Cement-lined pipe 300, 2000 Troubleshooting • Hot-tapping 800 • Hydrates 800
Developing a Purchase Specification Model Specifications, Specification disk Filling Out a Data Sheet Data Sheet Guides
Selecting the Best
• Line pipe 310, 400 • Pipeline route 200 • SCADA system 500
• Coating 340, 350, 440 Selecting appropriate inspection and testing for
pipe-lines
700 Selecting appropriate inspection and testing for line
pipe
300, 700, Data Sheet Guides Locating information related to pipelines (components,
coatings, welding, insulation)
Fig. 50-2 Manuals Cross Reference Chart (1 of 2)
PPL PIM FFM COM CPM WEM IRM ICM
Abandonment X Anchors X X Coatings External X X X Insulation X Internal X Selection Chart X X Weight X Components
API 5L Line Pipe X
ASTM A106 Pipe X
Instruments X
Insulation X
Valves and Fittings X X Computer Programs X X Construction Cathodic Protection X Coating X X X Inspection X X X X Offshore Methods X X X X Testing X X X Welding X X X Design ANSI/ASME B31.3 X ANSI/ASME B31.4 ANSI/ASME B31.8 X Hot Oil X X X Metering X Pipeline X Plant Piping X SCADA X Expansion X X Hot Tapping X X
Hydraulic Calculations X X Inspection and Testing X
Installation Crossings X Pipeline X Plant Piping X Pipe Cleaning X X Plant Piping X Pulsation Control (Surge) X Row Cleanup X
Specifications
C.S. Piping Fabrication X Cement-Lined Pipe X
External FBE Coating X Induction Bonding X
Internal Coating Tubular X
Insulation X
Line Pipe X
Pressure Testing of Plant Piping X Radiography X
Sour Line Pipe X
Startup X
Surveying X Troubleshooting X
Fig. 50-2 Manuals Cross Reference Chart (2 of 2)
Abstract
The Pipeline Manual is a guide for the basic design and construction of pipeline systems. It focuses on design fundamentals, guidelines for practical installations, and specification and purchase of materials and services. It is applicable to small gathering pipelines, large transmission pipeline systems and offshore pipelines. Its guidelines encompass the experience of the Corporation’s Operating Companies. The manual’s broad applicability makes it useful to both engineers and operating personnel.
The Pipeline Manual is concerned only with pipelines. It does not provide design information for pump stations, compressor stations or tank terminals, even though these facilities may be covered by the pipeline design codes. The manual includes certain topics related to operations and maintenance, but not a comprehensive description of these functions.
The Pipeline Manual organizes in one place much of the Company’s information on pipelines, presented in guideline form. It includes Company specifications which are easily used by any Operating Company. Industry standards are also included. For some subjects it advises reference to the more complete discussions in other ETD manuals. Contents Page 110 Contents 100-2 120 Code Compliance 100-2 130 Legal Requirements 100-3 140 Engineering Judgment 100-4
110 Contents
The Pipeline Manual is organized into two parts:
Part I - Engineering Guidelines
• Section 100 provides a road map for the entire manual, and background infor-mation on engineering style.
• Section 200 describes how to select a pipeline route.
• Section 300 describes the selection of the physical parts of a pipeline: the pipe, components and coating.
• Section 400 explains pipeline design and the Company’s preferred methods. • Section 500 tells how to monitor your pipeline system by using SCADA
systems.
• Section 600 discusses pipeline construction activities and contracting.
• Section 700 tells you how to ensure a good product through careful inspection and testing.
• Section 800 explains some operations and maintenance considerations that help produce practical designs.
• Section 900 covers the subject of offshore pipeline design and construction, discussing the differences and recapitulating the similarities between onshore and offshore pipelines.
Part II - Specifications
• Section 2000 introduces the Specifications part of the manual and tells you how to use the documents contained there.
• The Company Specifications section contains model format specifications with comments and their corresponding data sheets.
• The Standard Forms and Drawings section contains forms and drawings that pertain to the pipeline guidelines in this manual.
• The Industry Codes and Practices section provides the industry specifications and practices that the Guidelines and Company Specifications reference. • The Appendices provide references, conversion tables, sample specifications,
sample guidelines, and background design calculations.
120 Code Compliance
The various pipeline codes (such as ANSI/ASME Codes B31.4 and B31.8 in the United States) contain practices necessary for safe pipeline systems, but are not intended to be complete specifications for all phases of design. The Company recog-nizes this fact, and the guidelines and specifications in this manual provide the
supplemental requirements normally needed to obtain economical systems for basic fluid services. A few requirements—where experience has shown them to be better choices—are more stringent than code minimums. Engineers responsible for design and construction of pipelines are expected to be familiar with and to comply with the appropriate codes even though some of their provisions may not be specifically included in this manual.
130 Legal Requirements
In general, pipelines which conform with ANSI/ASME Codes B31.4 and B31.8 will meet the legal requirements in the USA for gas and liquid pipelines and facili-ties such as pump stations and compressor stations. See Section 400 for elaboration. In the United States, the Occupational Safety and Health Act (OSHA) is mandatory. Other countries have similar legislation. For general petroleum industry piping, the major effect of OSHA is on construction safety and to forbid the use of regular cast iron for flammable or combustible liquids having a flash temperature below 200°F or a temperature within 30°F of their flash temperature. Steel, ductile cast iron or malleable cast iron are required. The details of OSHA regulations are still changing, and the most recent revision should be reviewed where the economic effect of this requirement is considerable.
Pipeline activities in Canada are governed by the CAN3-Z183 and CAN/CSA-Z184 pipeline codes, and the CAN3-Z245 line pipe code.
Some states and localities in the United States have adopted some sections of ANSI/ASME Code B31; however, it is not a legal requirement in most states. OSHA regulations strongly encourage use of Code B31 by stating that compliance with Code B31 and specific OSHA rules is prime facie evidence of compliance with OSHA basic requirements.
The United States Code of Federal Regulations, Title 49, Part 192 and Part 195 (49 CFR 192 and 195) cover interstate and continental shelf oil piping and essentially all gas transportation piping. They define the minimum design requirements for oil and gas pipelines. Pipelines regulated by 49 CFR 192 and 195 are the responsibility of the Department of Transportation (DOT). 49 CFR 192 does not incorporate Code B31.8 by reference, while 49 CFR 195 does incorporate Code B31.4 by reference. However, Codes B31.4 and B31.8 contain supplemental design information and their use is recommended. In case of conflict, the applicable part of 49 CFR will govern.
The United States Code of Federal Regulations, Title 30 Part 250 (30 CFR 250) covers oil, gas, and sulfur operators in the continental shelf. Pipelines regulated by 30 CFR 250 are the responsibility of the Department of the Interior (DOI). 30 CFR 250 covers flowlines, platforms, separation facilities, pumps, and compressors upstream of the first flange on the sales pipeline, which is usually a DOT responsi-bility pipeline. See Section 900 for explanation.
Engineers responsible for design and construction of pipelines in the United States are expected to determine which codes are legally required and if there are any other federal, state, or local regulations governing such construction. The Company
requires compliance with the most stringent practice. For installations outside the United States and Canada, the engineer responsible for piping design and construc-tion should determine if there are naconstruc-tional and local regulaconstruc-tions pertaining to piping design. The ANSI/ASME codes remain good guidelines where no other regulations exist.
140 Engineering Judgment
The use of these Guidelines does not eliminate the need for sound engineering judg-ment. A few examples of special cases that are not covered by these guidelines and that should be given special consideration are:
• Extraordinary service conditions such as earthquake, high wind, other unusual dynamic loadings, or unusual superimposed dead loads
• Cold climates that may require special materials to avoid brittle fractures • High H2S concentrations that may place restrictions on valve trim and weld
hardness
• Consider upgrading of Class 150 flanges to Class 300 flanges where frequent blinding is required
It is necessary that the user of this manual realize that its use does not release him
from his responsibility to use sound judgment in the selection of materials,
fittings, valves, and other piping items to meet safety and economic considerations. No attempt has been made to provide for all the in-between or gray areas.
Some examples of areas where variations could apply: • Use of lighter wall pipe for low pressure systems
• Use of higher yield strength materials when economics dictate
• Variation in corrosion allowance or selection of material for handling of corro-sive/erosive material
150 Mandatory and Recommended Practice
For the most part, this manual covers RECOMMENDED practice. However, certain codes govern some activities and require that the design and materials conform to a specific standard. These codes are therefore mandatory.
MANDATORY in this context means that the engineer and/or operating personnel selecting equipment must conform to the selections as required by the governing code in order to meet minimum safety standards and govern-ment requiregovern-ments.
The following definitions also apply throughout this manual:
SHALL and IS REQUIRED mean mandatory per code and/or Company
SHOULD means advisory guidelines that are to be adhered to where no overriding
objections are apparent. An advisory guideline represents a design which is appli-cable in most cases and represents the experience and expertise of the Company.
PREFERRED and RECOMMENDED mean guide-lines which are generally and
successfully used within the Company, but there are other choices and methods which are acceptable.
MAY means acceptable or permitted options.
The above definitions are the same as those used in the Company’s
Abstract
This section focuses on the route selection decisions and activities that occur at the beginning of a pipeline project and influence the character of the entire project. Issues covered include preliminary route selection, project planning, regulatory and jurisdictional research, surface considerations, environmental and technical surveys, and final alignment and surveying. Careful and complete project planning mini-mizes project cost and duration. This section was developed with a large cross-country pipeline in mind, but most of the concepts can also be applied to smaller jobs and offshore pipelines.
Contents Page
210 Preliminary Route Selection 200-3
211 Hydraulic Profiles and Pump Station Locations 212 Input on Right-of-Way and Permitting Procedures
220 Project Planning 200-4
230 Jurisdiction, Permitting, and Rights-of-Way 200-6
231 Governmental Jurisdictions 232 Land Jurisdictions
233 Permitting
234 Private Right-of-Way Acquisition
240 Surface Considerations 200-9
241 Surface Conditions 242 Environmental Surveys 243 Technical Surveys
250 Alignment, Surveying, and Mapping 200-11
251 Published Maps and Aerial Photography 252 Surveying and Mapping Services
253 Aerial Photography and Photogrammetry 254 Field Surveying and Mapping
255 Route Alignment Sheets and Design Drawings 256 Special Survey Systems
210 Preliminary Route Selection
Preliminary route selection involves applying common-sense engineering to the problem of identifying reasonable deviations from a straight line between points A and B. These deviations are dictated by the need for an economic route and by the requirements of permitting agencies. Suitable maps are required to select a route and to determine the length of the pipeline; these should show contour lines, rivers, roads, railroads, towns, existing pipelines, and other topographic features. For long cross-country pipelines a World Aeronautical Chart is very useful. These are readily available for most parts of the world. For lines in the United States, U.S. Geological Survey maps of an appropriate scale give more detail, and are especially useful for shorter lines and critical areas. Aerial photographs, if available, also show certain topographic details.
Common-sense reasons to deviate from the straight line include the following: • To avoid significant natural obstacles such as mountains, rock, swamps,
unnec-essary river crossings, etc., and to select favorable locations for crossing moun-tain ranges, rivers, etc. However, extensive deviation to avoid difficult terrain should be evaluated to determine whether the lower construction cost per mile offsets the added length of line and the probable higher pumping costs
• To avoid developed areas such as towns, industrial areas, residential areas, intensive cultivation, etc., where right-of-way, construction, and construction damage costs will be high
• To minimize control points in hydraulic profiles. See the discussion of
hydraulic profiles in Sections 420 and 430 of this manual. Additional pumping power may be needed to overcome hydrostatic heads to clear control point elevations, particularly where the control point is near the end of the line or the inlet to a pump station
• To improve access for pipeline construction material and equipment—as well as for operations and maintenance—by using existing roads, including unim-proved roads adequate for pipe-hauling trucks
• To avoid government-restricted or environmentally sensitive areas and to reduce right-of-way and construction damage costs, if the information on these areas is available when a preliminary route is initially being studied. This infor-mation should be developed concurrently and factored into the route selection process as soon as it is available (see Section 210). Depending on the nature and complexity of these considerations, either a single preliminary route will be the obvious selection, and steps to develop a final alignment can proceed, or one or more alternative routes will warrant evaluation. Route selection may be influenced by right-of-way and permitting conditions as well as economic comparison.
211 Hydraulic Profiles and Pump Station Locations
Once an initial route has been identified, the ground profile should be plotted on cross-section paper, and a preliminary hydraulic profile should be developed using
the method discussed in Section 420. This should also be done for any alternative routes under consideration.
The hydraulic profile indicates approximate locations for intermediate pump stations for both initial and future design line throughput capacity. Pump station location may slightly influence final pipeline alignment, because of land avail-ability, station access, electric power access, etc.
212 Input on Right-of-Way and Permitting Procedures
Gathering of information on right-of-way and permitting procedures should proceed concurrently with route selection, preliminary engineering for line sizing, and cost estimates. This input is vital in developing the preliminary route that will be the basis for detailed engineering, acquisition of rights of way and permits, envi-ronmental and technical surveys, and final route alignment surveying.
Besides those of the Company operating organization that the pipeline facility will serve, Company resources at this stage normally should include:
• Engineering
• Land
• Governmental affairs • Environmental affairs
These groups usually can offer pertinent background information on route selection and procedures involved in obtaining rights of way and permits, and can develop plans to identify the appropriate authorities involved in granting rights of way and permits. For a cross-country or offshore pipeline, early development of a schedule for permit applications and approvals, environmental and technical surveys to support these applications, right-of-way acquisition (including condemnations, etc.) is essential.
220 Project Planning
Basic planning and coordination for all phases of the project should be initiated early in the project, so that project progress is not stalled by such road blocks as extended permit application procedures, changes in design basis, (such as line throughput forecast or fluid properties), prolonged permitting processes, right-of-way acquisition difficulties, pipe delivery delays, contracting surprises, and prob-lems in staffing and equipping field forces. Project planning for a major pipeline should cover the following:
• Pre-appropriation request phase
– Conceptual design and cost estimates, based on a reliable line throughput forecast and best available information on fluid properties
– Rheological testing, if needed to establish or confirm fluid properties – Definition of procedures and arrangements for permit applications,
initiation of these surveys and studies as appropriate to meet permitting schedules
– Preparation of an Appropriation Request and economic analysis, and a Contracting Plan
• Project development of the approved project
– Designs
– Acquisition of permits and rights of way, including finalizing environ-mental impact reports
– Procurement of construction materials – Arrangements for temporary field facilities – Further environmental and technical surveys – Field alignment and property surveys
– Preparation of contract specifications and bidding papers – Contract awards
– Project controls and reports
• Construction and project completion:
– Contract administration, field engineering and inspection, materials control – Field contracting
– Field purchasing, if appropriate – Project controls and reports
– Completion tests, dewatering, and turnover to the operating organization – Construction damage claim settlements
– Documentation and reports to permitting authorities – Record drawings for completed facilities
For offshore projects key elements of front-end engineering and detailed design development are indicated in Section 930, Figures 900-1 and 900-2. Many of these elements apply to onshore projects.
Planning must also include staffing requirements for all phases of the project, devel-opment of personnel policies, arrangements for extended work weeks and travel and field expenses, arrangements for borrowed personnel, etc. See the guidelines on the field supervision organization in Section 670 of this manual, and on the typical field inspection organization in Section 790.
Field support facilities must be carefully and realistically defined, so that offices, vehicles, and the communication system are ready and operational when needed. Mobility of field personnel and reliable communications are extremely important on a pipeline project. Field personnel are spread out geographically; they must be able to travel the route and to communicate with other field people and the construc-tion office base at all times. Vehicles and the communicaconstruc-tions system must suit the terrain, and acquiring them often involves long lead times. With few exceptions four-wheel drive vehicles and two-way radios are necessary along the route, and key construction office personnel should have radio-equipped vehicles.
A Project Contracting Plan is required by Corporation Policy 500 for large projects, and should be prepared for all projects to summarize intended contracts and timing. Dependent on contract scope and circumstances, contracts may cover: • Front-end engineering, providing conceptual design, cost estimates, and
prepa-ration of specifications for detailed design, procurement and construction • Surveying and mapping, and environmental and technical surveys as needed
for route selection, permitting, and design development • Specialist assistance for right-of-way and permit acquisition • Technical research and testing, as may be needed
• Design and procurement, if not done in-house
• Construction of the facilities, usually separately for the pipeline and for stations and terminals
• Construction support services, including radiographic inspection, nondestruc-tive testing, and hydrostatic test witnessing
• Supplemental personnel
• Temporary facilities and utilities
Contracting guidelines are included in the Construction and Services Contract
Manual. The Contracts staff of the Engineering Technology Department can be
consulted regarding types of contracts, contract forms, compensation items, and contractor performance. Also, see the discussion on construction and
construc-tion service contracts in Secconstruc-tion 680 of the manual.
230 Jurisdiction, Permitting, and Rights-of-Way
231 Governmental Jurisdictions
United States interstate and intrastate hazardous liquid and gas pipelines are feder-ally regulated except in the case of intrastate pipelines where a state has adopted standards that are the same as or more stringent than the federal standards. Chevron Pipe Line Company’s Guide to Pipeline Safety Regulations provides the informa-tion needed to determine jurisdicinforma-tion for pipelines. Chevron Pipe Line Company in San Francisco should be consulted for guidance on current federal and state regula-tions.
The applicable federal regulations are contained in Code of Federal Regulations Title 49, Part 195 (49 CFR 195), for liquid lines and 49 CFR 191 and 192 for gas lines. Canada has comparable federal and provincial regulations, although the prov-inces have more central control over intraprovincial activities. Regulatory jurisdic-tions are further discussed in Secjurisdic-tions 410 and 910 of this manual.
232 Land Jurisdictions
Except for production flow and gathering lines lying entirely within Company prop-erty, a cross-country pipeline traverses either privately owned lands or agency-administered lands under municipal, county, state or federal government jurisdic-tion. County records offices are the best source of ownership information and addresses for owners and agencies.
In general, permits or agreements for construction and operation of a pipeline system are granted by government agencies or owners of existing crossed facilities, such as highways, roads, railroads, canals, pipelines, and power and telephone lines. Rights-of-way, on the other hand, are needed to enter privately-owned lands for construction and maintenance of a pipeline.
233 Permitting
Permitting procedure and timing must be determined for each governmental agency and owner of an existing crossed facility. These will vary from agency to agency, and not infrequently from time to time for the same agency. This information must be developed as soon as possible so that priorities can be given to permitting proce-dures that take the most time, or where sequential permit approvals are dependent on prior approval by other agencies. Permitting authorities should be contacted at an early stage regarding anticipated permit conditions and requirements affecting construction, so that these can be incorporated into construction specifications before inviting bids.
In the U.S., preparation, review and approval of an Environmental Impact Report (EIR) is now required for nearly all cross-county pipelines. Under guidelines of the National Environmental Policy Act (NEPA), the EIR process can add over a year to the project schedule. Project timing and funding must allow for this. A number of governmental agencies are likely to be involved in the EIR process, in addition to the one(s) with jurisdiction over the land which the line traverses. One agency is assigned as the lead agency, and has the responsibility for coordinating the others and for conducting the public hearing and response process.
The EIR requires significant front end engineering to thoroughly cover the proposed construction, since, once approved, permit conditions and mitigation measures cannot be changed.
Preparation of the EIR, along with required surveys and the review, takes time. Scheduling should make realistic allowances for this process, and every effort should be made to keep the process on schedule. Environmental and technical surveys are discussed in Section 240. Requirements for supplemental documenta-tion, such as a construction operating plan, copy of the construction specificadocumenta-tion, etc., should be determined for each permitting authority.
All permits should be obtained before starting construction, since unforseen delay in granting a permit after construction starts will interrupt work and lead to high standby charges. In some cases permitting authorities will issue a letter giving approval to proceed pending formal execution of the permit.
A Company land department is normally assigned responsibility for permit applica-tions by the pipeline operating organization, coordinating with governmental affairs, environmental affairs and engineering organizations. Close coordination between these groups is essential, both for exchange of information and to assure that responsibilities for action by the various groups are clearly defined.
234 Private Right-of-Way Acquisition
A typical right-of-way document is in a form prepared by the Company, by which a private land owner gives the Company, for a consideration, the right to construct and maintain one or several pipelines within a specified width across the property, with reasonable access over the property to the lines. In some right-of-way agree-ments for undeveloped lands the location of the right-of-way may be defined by the center-line of the first pipeline laid, but usual practice is to legally describe the route on the property. Usually the width of the right-of-way is less than the working strip needed for construction of the line, but the negotiated right of access allows the Company to use the additional width needed for construction.
A right-of-way agreement is negotiated with each property owner. Payments for rights-of-way are, preferably, uniform for all owners. However, adjustments are usually necessary, depending on differing land values and difficulties in negotiating with particular owners. If a landowner adamantly refuses to grant a right-of-way, common carrier pipeline companies may use the right of eminent domain to obtain the right-of-way by taking legal action. The conditions for and duration of this legal process vary from state to state.
In many cases additional special conditions for the particular property are incorpo-rated in the right-of-way agreement. Where these special conditions affect construc-tion, they should be summarized in a sequential list according to their occurrence along the route. This information should be distributed to Company field personnel and contractor supervisory personnel so that construction meets the special condi-tions, for instance, extra depth of cover, protection of water aquifers and springs, protection of vegetation, specified seed mixtures for revegetation of rangeland. Payment for damages to the property resulting from construction and maintenance of a pipeline is separate from payment for the right-of-way, although in some cases costs for damages can be agreed in advance of construction, and damage payment is made at the same time as payment for the right-of-way. Construction damages include damages both within the specified width defined in the right-of-way agree-ment and on the construction working strip outside the right-of-way width, and any other damage to the property as a consequence of pipeline construction activities. Where damages result from unnecessary and avoidable acts by the contractor, a method to allocate such costs to the contractor or by which the contractor settles directly with the landowner or tenant, should be provided for in the construction specifications.
Right-of-way acquisition, as for permit acquisition, is normally the responsibility of a Company land department, which often directs contract right-of-way agents. Close coordination with field engineers handling detailed routing and alignment surveying is essential. Land Department representatives are also responsible for
damage claim settlements. Here again close coordination with field construction engineers is important when the nature and extent of damages and the responsible parties are in dispute.
240 Surface Considerations
After establishing a preliminary route as described in Section 210, preliminary alignment photography and/or surveying is done, and environmental and technical surveys are initiated, as appropriate. Priorities must be given to the portions of this phase that are on the critical path for permitting and design.
241 Surface Conditions
Information is developed from the preliminary alignment photography and/or surveying on:
• Natural features and agricultural lands. Rivers, streams, water courses,
swamps, canals, rocky terrain, irrigated cultivation, dry-land cultivation, range land, forests, etc.
• Surface improvements. Existing highways, roads, railroads, pipelines, cables,
power and telephone lines, etc.
• Buildings. Existing buildings and structures. For gas pipelines, density of
buildings along the route is a critical element in design; see Section 430. Highway, railroad, and irrigation canal authorities; owners of pipelines, power lines, and telephone cables; and local authorities should be queried regarding future developments of their systems or of residential and industrial areas that might affect pipeline routing or design.
Where the preliminary pipeline route roughly parallels existing pipelines, govern-mental authorities and private landowners are likely to require that the proposed line be located in a corridor with the existing pipeline(s). In such cases it is prefer-able for construction and maintenance access and safety that the new line be on the opposite side of the corridor from the existing line(s), or, failing this, that ample spacing be provided so that excavation and construction equipment will not jeopar-dize the existing line(s).
Preliminary site inspection at major river and stream crossings should be made to establish tentative crossing locations, for which technical surveys will be made.
242 Environmental Surveys
Federal and state regulations provide for protection of significant cultural features and threatened and endangered wildlife, and require surveys of potentially sensitive areas along the route to identify the existence of such areas. If any are found, the relevant authority determines the extent of further investigation and the effect on line routing, conditions for construction, or required mitigation measures. Contracts for these surveys are subject to overruns, because the scope cannot be defined at the
outset. In essence, the purpose of environmental surveys is both to determine what
is there and to establish what must be done to mitigate or investigate further.
Typical environmental surveys cover: • Archeological and historical features • Fish
• Birds • Other fauna • Plants
• Paleontological features (fossils)
Information developed by these surveys can lead to:
• Adjusting the pipeline route alignment to avoid sensitive areas
• Completing archeological, historical, and paleontological studies at identified sites before construction—if construction can then be allowed through the sites • Scheduling construction activities in areas to avoid critical periods for fish and
wildlife, such as breeding, nesting, spawning seasons
Environmental surveys are performed by environmental engineering contractors or independent specialists, often associated with staffs of university departments. These professional service contracts are usually performed on an all-in reimburs-able basis for labor and equipment rental rates, with per diem allowances for field expenses. Comparative proposals should be obtained wherever feasible. Environ-mental Affairs, GovernEnviron-mental Affairs, Engineering Technology Department, local Company offices and the permitting authority may be consulted regarding contrac-tors or specialists recognized and accepted by authorities for expertise in the various categories of environmental surveys.
In some areas, government agencies have conducted surveys and predesignated significant cultural resources. Maps of these features are generally available from the agencies involved. This information may save retaining an environmental contractor.
In many cases archeological, historical and paleontological field work is done after construction excavation in potential sites in search of any significant evidence in the trench or spoil that warrants further investigation. If such evidence is found,
construction work in the area must stop, and either be deferred until investigation and studies are complete, or proceed on a relocated route which skirts the site. Judgment should be used in controlling the extent of environmental surveys. Suffi-cient work must be done to expeditiously meet permitting conditions, but reason-able limits should be set on investigation beyond the required scope that the specialist field team may want to do at Company expense.
243 Technical Surveys
Depending on terrain and physical conditions along the route, technical studies of some kind will usually be needed for the permitting procedure or for design. Typi-cally, these are as follows:
• Geophysical surveys in areas of soil instability or earthquake activity. These identify areas of concern that warrant further investigation to develop recom-mended measures to protect the pipeline, or to adjust the route alignment to avoid or reduce the hazard
• Geotechnical and hydrological surveys at river and stream crossings to develop data on soil properties, predicted scouring and bank variation, and seasonal and historical variations in flow
• Geotechnical surveys at highway, road and railroad crossings if needed to determine soil properties and water table data for bored crossings, both cased and uncased
• Geophysical and meteorological surveys for heated lines to determine ground and air temperatures, and soil conductivity properties, or for water slurry lines to determine ground temperatures and frost depths
• Meteorological surveys to determine weather conditions during the scheduled construction period
• Geotechnical, hydrological and meteorological surveys may be needed to develop spill contingency plans for oil lines
Technical surveys may involve only a literature search, or a combination of litera-ture search, field investigation, and lab testing, as determined by the circumstances. Professional service contracts with reputable engineering and technical contractors should be used for technical surveys. The Civil and Structural Division of the Engi-neering Technology Department can be consulted for recommended contractors for these surveys.
250 Alignment, Surveying, and Mapping
Initial routing of the pipeline and the preliminary route selection, possibly with alternatives, are based on existing published maps and aerial photography, as discussed in Section 210. Field surveying is usually needed in conjunction with environmental and technical surveys—to mark the preliminary route, to survey proposed crossings, to record locations of soil borings, soil samples, archeological sites, etc. Aerial photography may also be done at this time.
When a firm route alignment has been developed, field surveying is done to tie the alignment to land survey monuments and to obtain data for alignment maps and crossing profiles, right-of-way maps, and property maps for station and appurte-nance sites. The alignment may be flagged on certain properties to support right-of-way acquisition. At the time of construction the alignment is staked ahead of the
construction crews, any minor alignment relocations are surveyed, and record data for the completed facility are obtained.
251 Published Maps and Aerial Photography
Maps suitable for route selection include the following:
• World Aeronautical Charts. These show significant topographic features;
scale is 1:1,000,000 (1 inch = 16 miles). They may be obtained from aircraft charter and service firms, or from Department of Commerce, National Oceano-graphic and Atmospheric Administration, Rockville, Maryland, 20852.
• U.S. Geological Survey maps. These show more detailed topographic features
and ground cover. Scales are: 1:250,000 (1 inch = 4 miles); 1:125,000 (1 inch = 2 miles); 1:62,500 (1 inch = 1 mile); 1:50,000 (1 inch = 0.8 mile). Maps may be obtained from Operating Company map and drafting records groups, local map supply stores, or the U.S. Geological Survey, Denver, Colorado, or Reston, Virginia. For some areas USGS also has information on geology, flood plain areas, hydrological data, land use and orthophoto maps (with aerial photo background).
• Canadian Geological Survey maps are similar to USGS maps.
Aerial photographs may be available from government sources to supplement maps for preliminary route selection. A scale of approximately 1:36,000 (1 inch = 0.6 mile) is good for route selection. With about 60% overlap of photos, stereo viewing will show exaggerated ground relief and is useful in laying out the route in rough terrain. Enlargements are useful in selecting station and appurtenance sites. Sources for aerial photography include the following:
• U.S. Geological Survey
• U.S. Bureau of Land Management • U.S. Bureau of Reclamation • N.A.S.A.
• Commercial aerial photography services
Operating Companies periodically fly their own aerial photography surveys, espe-cially for new exploration areas. Contact your map and drafting records group. Similar topographic maps and aerial photos are usually available from local govern-ment sources in other countries.
252 Surveying and Mapping Services
Careful selection of a surveying and mapping services company for the project is important, since work must be done accurately, field crews must be available when needed, and maps must be prepared quickly after the field data is in hand. The expected scope of services required for the project should be clearly presented to several reputable land surveying companies and discussed with them to develop information on their capabilities and commitment to meet the expected needs. From
these prequalification meetings a short-list should be invited to submit proposals. For a long cross-country line it may be advisable to contract sections of the route to different surveying companies. In this case, make arrangements for similar presenta-tion of data by each contractor.
The surveying company should be equipped with electronic distance measuring instruments and computerized theodolites, and be able to produce maps within 24 hours, when necessary.
Mapping for permit, right-of-way, and land acquisition should be done by the land surveying contractor. Alignment sheets and crossing detail drawings, both for construction and for record, are usually prepared by the project engineering organi-zation using survey data from the surveying company, since these drawings incorpo-rate more information than just the definition of the route.
The contract schedule of payments for surveying and mapping services should be complete and precise in covering all items of cost anticipated for the work. Compen-sation is normally on an hourly or daily reimbursement basis for field crews and office personnel, with added items for special equipment, field expenses, printing and reproduction, etc.
Aerial photography and photogrammetric mapping and engineering are often advan-tageous and economical. The land surveying company may have this capability, or, more likely, will subcontract this phase of work. Compensation for such work should also be defined in the contract schedule of payments at the time of award. On large projects or projects in remote areas sophisticated inertial or satellite surveying systems may be applicable. These may be provided within the surveying and mapping services contract or may be contracted for separately, in which case close coordination is required with the conventional field surveying crews.
253 Aerial Photography and Photogrammetry
After a preliminary route is selected for a cross-country pipeline and the project is approved, it may be economical and expeditious to arrange for aerial photography along the route. Aerial photographs may be uncontrolled—by flying at a certain elevation above the ground to give an approximate scale—or controlled by using known surveyed ground reference points and photogrammetric methods to produce accurately scaled photographs. Uncontrolled aerial photography is considerably less expensive than controlled, and may be satisfactory for wilderness or remote areas where accurate right-of-way mapping is not critical. However, in the United States and other developed countries controlled aerial photography and photogram-metric mapping is usually made economical by the saving in costs and time for field survey crews and office engineering and drafting, and will provide the back-ground for final alignment sheets.
Photogrammetric methods can also produce elevation data and contour maps. Aerial mosaic strips, marked to show the pipeline with a simplified route alignment map, are useful in describing the route to bidders for construction of the line.
Usually, aerial photography is done early in the design phase of the project, but there may be situations in wilderness and remote areas in which the cost of
controlled aerial photogrammetry done after construction, with the cleared working strip and markers over the pipeline visible, will be offset by reduced field survey costs.
254 Field Surveying and Mapping
Control surveys are done on the ground, based on existing government monuments or other accepted monuments with established location coordinates and elevations. Control surveys are usually made to a high order of accuracy (second order or better). They provide the basic network for all other surveying and mapping during the design, right-of-way, and property acquisition and construction phases of the project. The cost of setting up the survey control network is usually significant. Control points should be well documented, and semipermanent monuments installed. This is particularly critical if there should be a change in surveying company between initial surveying and construction surveying.
The route centerline alignment is tied to government monuments, property corners, and boundaries and to the monuments established by the control survey. The route is defined by the points of intersection (PI’s) of the straight lines identifying the route, the horizontal lengths, or tangents, between PI’s, and the bearings, or
deflec-tions, of the tangents. Preferably, the initial and final points of the line should be
stated in Lambert grid coordinates, or another standard grid system adopted by the governmental survey authority for the area.
Typically, permit and right-of-way maps show ties to controlling property corners, and the dimensions and areas of right-of-way parcels. Specific requirements for monumenting the right-of-way and preparing right-of-way maps and documents vary from place to place. The Manual of Instructions for the Survey of the Public
Lands of the U.S., issued by the U.S. Bureau of Land Management, governs
proce-dures for land surveying.
Field surveying must also be done at the design phase for: • Ground reference points for controlled aerial photography • Route alignment sheets
• Crossing detail drawings • Site topographic maps
The alignment is staked at the time of construction. Offset stakes are set from the pipe centerline, usually at 200-foot intervals, and marking stakes are set with hori-zontal stationings. These stakes define the pipeline for construction—locating the pipe centerline and locations for changes in pipe wall thickness, grade or coating, appurtenances, extra depth of cover, etc. This staking continues during the construc-tion period; if it is done too far in advance of the construcconstruc-tion crews, stakes may well be lost before the trench can be excavated.
Construction staking may be done either by the Company’s surveying contractor or by the pipeline construction contractor. If done by the construction contractor, the Company field engineer should ensure that clearly marked base survey stakes are in place (by which the construction contractor will set his offset stakes) and that the construction contractor’s survey crew is competent.
Field surveying may also be needed during the construction period to lay out and stake minor realignments during the course of construction. Field surveying should be done when installing river and stream crossings so that the location and depth of the line, and river bottom and bank profiles are accurately recorded.
When the pipeline is in the ground and all work is essentially complete, field surveying is done for record purposes. Slope distances along the line are measured, corresponding to the actual length of pipe. From these, slope stationings for PI’s, pipe and coating changes, crossings, appurtenances, fence lines, pipeline markers, etc., can be derived and shown on the final record alignment sheets.
255 Route Alignment Sheets and Design Drawings
These drawings are prepared by the project engineering organization for construc-tion and as a record of the completed pipeline facility. Because the line is generally buried, and lies on property not owned by the Company, accurate records of the line as constructed, or, subsequently, as modified, are particularly important.
As prepared for construction, route alignment sheets define the route, with
hori-zontal stationings (the cumulative distance from a starting point of the line, such
as the scraper trap mainline block valve at the initial pump station). The alignment sheets typically also show:
• Right-of-way width, and position of the new pipeline(s) within the right-of-way • Ground elevation profile
• Pipe minimum cover
• Pipe size, wall thickness, grade, manufacturer • Pipe coating
• Appurtenance locations, including cathodic protection rectifier stations, anodes, and test stations, with references to detail drawings
• River and stream crossings, with references to detail drawings
• Highway, road and railroad crossings, with references to detail drawings • Foreign and Company pipeline crossings, with references to detail drawings • Underground cable and telephone lines
• Overhead power and telephone lines
• Property ownership, and permit and right-of-way reference numbers • Types of vegetation or cultivation
Crossing detail drawings show plan and profile views for each crossed facility (river, stream, highway, road, railroad) and the pipeline. For cased crossings the casing, size, wall thickness and length are shown, and vents (if any), and the quan-tity and description of insulating spacer supports and casing end seals are listed. For crossings of pipelines and cables a typical drawing is usually prepared for all such crossings.
The record alignment sheets incorporate information on the completed pipeline, and show slope stationings for PI’s and all pipeline features. Horizontal stationings originally shown for the route and ties to monuments and properties should remain.
Horizontal stationings and slope stationings should be clearly differentiated;
for example, show all slope stationings within parentheses.
Chevron Pipe Line Company and the Civil and Structural Division of the Engi-neering Technology Department may be consulted for recommended format for alignment sheets and crossing detail drawings. See Figures 200-1 and 200-2.
256 Special Survey Systems
For surveys in undeveloped and remote areas, and where survey base monuments may be distant, special inertial or satellite survey systems should be considered. State-of-the-art equipment is continually improving, and available systems should be evaluated at the time of the project. These systems give latitude and longitude (or coordinates in a base system), and elevations, and can be effectively used to establish a network of project reference monuments along the route as a basis for conventional field surveying on the ground.
Example Alignment Sheet: Notes
(Notes to Figure 200-1)
A. Ownership
1. Line list number or parcel number identifies property or rancho boundaries crossed by pipeline and right-of-way.
2. Pipeline schematic and identification.
3. Right-of-way boundaries on either side of pipeline. Show width of R/W from centerline of pipeline.
4. Oval containing line list/parcel number identifies property entered by pipeline and/or easement. Numbers are consecutive along pipeline route.
5. Property lines are not to scale, but represent property limits only. Property plats determine if entire right-of-way or just a portion lies inside property.
6. If plat determines that property contains only easement (not pipeline), draw property line within right-of-way.
7. Property corner "ties" identify property limits more clearly (use a 1/16-in. circle).
8. "X" after line list/parcel number denotes a road crossing, "R" a railroad crossing. Show centerline and name of road or railroad. If crossing lies between two properties use lower property number.
9. Line out "stationing &" if not used.
10. Horizontal pipeline footage through a property. This footage is on property plat. Place footage number in line with line list/parcel number. Survey ties to property lines, section corners, etc., are horizontal distances.
11. Place property line stationing (if shown) vertically on left side of property lines.
B. Aerial
12. Show scale used.
13. Indicate information concerning "start" of an alignment, e.g., continuation drawing numbers, coordinate system reference, start of survey stationing and/or matching stationing from a previous alignment sheet.
14. North arrow.
15. Plot pipeline line to scale with points of intersection (PI) symbols (1/16-in. circles) indicating bearing changes. Plot valve symbols and bearings along pipeline.
16. List of PI’s and stationing.
17. Milepost marker with stationing to left of extension line. Extension lines extend to, but not through, pipeline line.
18. Line list/parcel number with leader to 1/6-in. dot at property location. Property corner ties help identify plat. Show only property crossed by pipeline or within right-of-way.
19. Identify county and state on each alignment sheet. 20. Identify any parallel pipeline(s).
21. Indicate road/railroad crossings with an oval, symbol and number, and leader to road/railroad centerline. To avoid confusion, set leader at an angle to the centerline.
22. Place crossing symbols as near point of crossing as possible. Make all symbols same size as in legend.
23. Show property, rancho and grant names and boundaries. Reference only proper-ties entered by pipeline. Show township and section lines with stationing.
C. Material Section
24. Pipeline line (same scale as aerial map).
25. Use extension and dimension lines and a box to identify pipe size, wall thick-ness, grade, pipe ends, pipe manufacturing process and coating type.
26. Give beginning and ending stationing for concrete coatings, weights and casings as found in field notebook.
27. Use and station cathodic protection symbols per legend and field notebook. 28. Place wall thickness (WT) changes next to extension line.
29. Show valves and refer to separate detail drawings if required.
30. Line up all matchlines. Indicate stationing and continuation sheets or start of survey information.
D. Class Location Section
43. For gas pipelines, show class location boundaries.
E. Alignment Section
31. Show pipeline as a straight line with PI and valve symbols spaced to scale of aerial strip.
32. Indicate crossings as found in field notebook. Place crossing symbols perpen-dicular to pipeline at about the same location as in aerial strip with spacing as much to scale as possible.
33. Place stationing and brief description of crossings below symbol in text portion. Stationing relates to inventory (slope) distances, not horizontal distances.
34. Indicate tie dimensions and reference in text when they appear in field note-book.
35. Line up all matchlines with each other. Indicate stationing and continuation sheets or start of survey information.
F. Profile
36. Record beginning station and end station.
37. Give elevation for centerline of pipeline. Use a consistent vertical scale on all alignment sheets, large enough to show elevation changes of concern to designer. In hilly terrain, break-points may be used.
38. Profile data is inadequate for calculating overbends and sagbends. Milepost markers are set at or near calculated miles, but should not interfere with land use.
G. Legend
44. Symbols used on alignment sheet. 45. Revision block.
46. Scale of aerial and alignment strips. 47. Date of plat.
48. Drawing title. 49. Drawing number.
Abstract
This section provides the engineer with guidance on selection of line pipe mate-rials, requirements for bending in the field and in the shop, and selection and appli-cation of coatings and linings for corrosion protection. Guidelines and
specifications are included. Specifications for line pipe materials, methods of bending, and internal and external coatings are also included.
Contents Page
310 Line Pipe Selection 300-3
311 Line Pipe Manufacturing
312 Selection of Grade and Wall Thickness
313 Fracture Toughness Requirements (Impact Testing) 314 Corrosion
315 Specifications and Selection for Specific Services 316 Pipe Purchasing 320 Field Bending 300-22 321 Code Requirements 322 Chevron Requirements 330 Shop Bending 300-24 331 Induction Bending 332 Hot Bending
340 External Pipeline Coatings 300-28
350 Internal Coatings and Linings 300-30
351 Epoxy Coatings 352 Plastic Linings 353 Cement Linings
360 Piping Components for Pipelines 300-38
362 Through-Conduit Valves
363 Closures and Appurtenances for Scraper Traps 364 Casing Insulators and Seals
365 Special Repair Fittings 366 Branch Connections
367 Wall Thickness Transition Pieces
370 Special Installations 300-43
371 Insulation on Buried Lines
372 Heat Tracing for Buried and Aboveground Lines 373 Nonmetallic and Corrosion Resistant Pipe
310 Line Pipe Selection
Line Pipe Specifications
The commonly used industry specifications for line pipe are API 5L and Canadian Standard CAN3-Z245.1. In 1994, ISO (International Standards Organization) adopted line pipe standards. These are ISO 3183-1, Technical Delivery Conditions for Steel Line Pipes for Combustible Fluids — Part 1: Pipes of quality level A; and ISO 3183-2, Technical Delivery Conditions for Steel Line Pipes for Combustible Fluids — Part 2: Enhanced quality level B. ISO 3183-1 is essentially based on the Fortieth edition of API 5L, November 1992. ISO 3183-2 has tighter chemical composition requirements, specific heat treatments and mandatory toughness requirements. It is similar to the Chevron specifications.
For both onshore and offshore pipelines the Company generally uses line pipe purchased with Model Specification PPL-MS-1050, Line Pipe for General Service. For sour service, PPL-MS-4041, Sour Service Line Pipe is recommended. Specifi-cations PPL-MS-1050 and PPL-MS-4041 (for sour service) are actually a list of requirements that supplement API specification 5L. These additional requirements are necessary to enable the user or project engineer to obtain state of the technology line pipe with assured weldability, NDE requirements and sour service performance.
311 Line Pipe Manufacturing
Pipe Making Processes
Line pipe is manufactured by several different processes. Chevron commonly uses seamless (SMLS), electric weld (ERW or HFI), and submerged arc welded (SAW) pipe. There is also helical or spiral welded submerged arc welded pipe, however its use has not been common in Chevron’s operations. Each process has its inherent advantages, disadvantages and suitability for different sizes of pipe. Refer to Figure 300-1.
Seamless Pipe
Manufacturing of seamless (SMLS) pipe begins with a solid round billet that is heated to about 2200°F and pierced to make a hollow cylinder. The cylinder passes through several hot (1800-2200°F) rolling steps to make a pipe with the desired size and wall thickness. Seamless pipe may be supplied as-rolled, or it may be heat treated after rolling to improve its properties. Either normalizing or quenching and tempering heat treatments may be used. Straightening if required is done either hot or cold depending upon the mill practice.
Seamless pipe has greater variation in wall thickness that welded pipe. Also the length variation in a particular lot or mill run is greater than welded pipe. The engi-neer is advised to clearly specify the acceptable length variations on the purchase order.
(1) The range represents the capacity variations for different manufacturers. (2) Above 1.25 in. refer to ANSI/ASME B31.4 and B31.8 for stress relief requirements.
Electric Welded Pipe (ERW or HFI)
Electric welded pipe is manufactured from a long, flat coiled strip called skelp that has been rolled to the desired wall thickness of the finished pipe. The strip has a width equal to the circumference of the pipe. In the pipe mill the skelp is fed through a series of rolls which form it into a cylinder. The edges are welded together using electric resistance (ERW) or induction (HFI) heating and pressure from the rolls to make a longitudinal seam. No filler metal is added to the weld, and after the “flash” from the weld is trimmed off it is difficult to visually locate the weld on the OD. At the ID the flash trimming operation creates a small depression which makes the weld line distinguishable in many cases. The narrow heat affected zone along the seam is heat treated (seam normalized) after welding using localized induction heating coils. EW pipe is usually not given an additional heat treatment Fig. 300-1 Typical Availability and Usage for Types of Pipe
Seamless EW (ERW or HFI) SAW Spiral Weld
Minimum Diameter(1)
2-3/8 in. or less 2-3/8 in. or less 16 in. to 20 in. 10 in. Maximum
Diameter(1)
16 in. (typical) to 26 in.
24 in. to 26 in. 64 in. to 84 in. 80 in. to 100+ in. Maximum
Wall Thick-ness (1) (2)
0.750 in. to 2.000 in. 0.312 in. to 0.750 in. 0.625 in. to 1.500 in. 0.500 in. to 1.500 in.
Grades B thru X-80 B thru X-70 B thru X-80 B thru X-70 Highly weldable X
grades may be heat treated by
quenching and tempering
X-52 and higher grades are made from controlled rolled skelp or quenched and tempered
X-52 and higher grades are made from controlled rolled plate
X-52 and higher grades are made from controlled rolled skelp
Acceptable Services
All services onshore and offshore
All services onshore; some offshore services. See Figure 300-2
All services onshore and offshore
USA experience limited to less crit-ical services. Used as equivalent to SAW in Europe, Canada, etc. Relative Cost More expensive than
EW. Cost premium may be significant for larger sizes (>10 inch)
Usually less expen-sive than seamless in sizes <10 inches. Almost always less expensive than seamless in sizes >10 inches. Large overlap in size range with seamless
In the small range of size overlap, usually less expensive than seamless but more than ERW
May be less expen-sive than long seam SAW
