Preface
This is the second edition of CSA Standard Z662, Oil and Gas Pipeline Systems. It supersedes the first edition, published in 1994. This Standard is part of the Pipeline Systems and Materials segment of CSA's Transportation program.
The delta symbols in the left margin identify parts of this Standard that have substantially changed from the previous edition. The following are the most significant changes, relative to the first edition:
(a) The scope of the Standard has been expanded to include pipeline systems that convey carbon dioxide used in enhanced oilfield recovery. Specific requirements relative to the design, materials, welding, and pressure testing of such pipeline systems have· been added at appropriate locations throughout the Standard.
(b) Ultrasonic inspection has been incorporated as an alternative to radiography for the nondestructive· inspection of pipeline girth welds. Requirements governing ultrasonic ·inspection methods and the evaluation of imperfections detected by ultrasonic inspection have been added.
(c) The requirements governing radiographic image quality indicators (previously penetrameters) have been revised to additionally reference wire-type image quality indicators.
(d) The requirements concerning the acceptability of imperfections and repair of defects on operating pipelines have been significantly modified to improve ease of understanding and provide more detailed guidance on the use of sleeve-type repairs. Specific requirements governing the application of fibreglass reinforcement repair sleeves have been added.
(e) The requirements for requalification of existing pipeline systems have been consolidated and simplified.
(f) The pressure design formulae for polyethylene gas distribution pipeline systems have been revised.
(g) The former Appendices B, C, and D have been removed, and Appendix E has been rewritten in mandatory language to accommodate its adoption by anyone wishing to do so.
(h) Non mandatory guidelines for the risk analysis of pipelines have been added as Appendix B.
(i) It is now permitted for steel oil and gas pipelines to be designed according to a limit states design process, as an alternative, where applicable, to the requirements of Clause 4. Detailed requirements for limit states design of pipelines have been added as Appendix C, which also incorporates a commentary providing technical background.
The requirements of this Standard· are considered adequate under conditions normally encountered in the oil and gas industry.
Requirements for abnormal or unusual conditions are not specifically provided for, nor are all details related to engineering and construction prescribed. It is intended that all work performed within the scope of this Standard meet the standards of safety and integrity expressed or implied herein.
It is expected that changes may have to be made from time to time based on new experience and technology. When necessary, amendments and supplements will be made by the Technical Committee and published in accordance with CSA practices.
CSA gratefully acknowledges the work of the editorial subcommittee, A.B. Rothwell and F.M. Christensen, in the preparation of this Standard.
This Standard, was prepared by the CSA Technical Committee on Oil and Gas Pipeline Systems under the jurisdiction of the Standards Steering Committee on Oil and Gas Industry Systems and Materials and was formally approved by these Committees.
Scope
1.1
This Standard covers the design, construction, operation, and maintenance of oil and gas industry pipeline systems that convey
(a) liquid hydrocarbons, including crude oil, multiphase fluids, condensate, liquid petroleum products, natural gas liquids, and liquefied petroleum gas;
(b) oilfield water;
(c) oilfield steam;
(d) carbon dioxide used in oilfield enhanced recovery schemes; or
(e) gas*.
*Designers are cautioned that the requirements in this Standard may not be appropriate for gases other than natural gas, manufactured gas, or synthetic natural gas.
1.2
The scope of this Standard, as shown in Figures 1.1 and 1.2, includes
(a) for oil industry fluids, piping in offshore pipelines, onshore pipelines, tank farms, pump stations, pressure-reducing stations, and measuring stations;
(b) oil pipeline pump stations, pipeline tank farms, and pipeline terminals;
(c) for carbon dioxide pipeline systems, piping in onshore pipelines, pressure-reducing stations, and measuring stations;
(d) for gas industry fluids, piping in offshore pipelines, onshore pipelines, compressor stations, measuring stations, and pressure-regulating stations;
(e) gas compressor stations; and
(f) gas storage lines and pipe-type and bottle-type gas storage vessels.
1.3
This Standard does not apply to
(a) design and fabrication of pressure vessels that are covered by appropriate pressure vessel codes;
(b) piping with metal temperatures below -70°C;
(c) piping other than oilfield steam distribution piping, with metal temperature above 230°C;
Note: Although not specifically covered by this Standard, designs for higher temperatures may be used, provided that the effects of such higher temperatures are accounted for.
(d) gas piping beyond the outlet of the customer's meter set assembly (which is covered by CGA Standard CAN/CGA-B149.1);
(e) piping in natural gas liquids extraction plants, gas processing plants (except main gas stream piping in dehydration and all other processing plants installed as part of gas pipeline systems), gas manufacturing plants, industrial plants, and mines;
(f) oil refineries, terminals other than pipeline terminals, and marketing bulk plants;
(g) in-plant piping for drinking, make-up, or boiler feed water;
(h) casing, tubing, or pipe in oil or gas wells, wellheads, separators, production tanks, and other production facilities;
(i) vent piping for waste gases of any kind operating at or near atmospheric pressure;
(j) heat exchangers;
(k) prefabricated units that employ plate and longitudinal welds rather than pipe;
(l) liquefied natural gas systems;
(m) liquid fuel distribution systems;
(n) loading/unloading facilities for tankers or barges;
(o) natural gas refuelling stations; and
(p) hydrocarbon storage in underground formations and associated equipment (which is covered by CSA Standard Z341 ).
1.4
This Standard is intended to establish essential requirements and minimum standards for the design, construction, and operation of oil and gas industry pipeline systems. This Standard is not a design handbook and the exercise of competent engineering judgement is a necessary requirement to be employed concurrently with its use.
1.5
The requirements of this Standard are applicable to the operation, maintenance, and upgrading of existing installations; however, it is not intended that such requirements be applied retroactively to existing installations insofar as design, construction, and established operating pressures are concerned.
1.6
Where any requirements of this Standard are at variance with the requirements of other standards or codes incorporated by reference into this Standard, the requirements of this Standard shall govern.
1.7
It is not the intent of this Standard to prevent the development of new equipment or practices, or to prescribe how such innovations should be handled.