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This text is abridged from the introduction to APGA's 2011 "Guide to AS285".

The role of this wiki is to help address the pipeline engineering skills shortage, and to better communicate the history and background to the development of the AS2885 suite of documents.

AS 2885 has evolved and expanded in order to meet the requirements of the Australian industry to reduce the cost of construction pipeline as well as maintain the existing high standards of safety and reliability.

The AS 2885 suite requires competent persons to make important decisions regarding pipeline design, construction, testing and operation. The requirement for competent persons is reflected in state legislation, regulations, and licensing regimes.

Users of this wiki should understand and commit to the fact that there is no substitute for reading the Standard and gaining sound perspective and understanding of its application to specific situation and problems.

DEVELOPMENT OF THE AUSTRALIAN STANDARD FOR PIPELINES

This text is abridged from the 2011 APGA Guide to AS 2885, Section 2.3

The first significant hydrocarbon transmission pipeline constructed in Australia was the DN500 "Lurgi" pipeline, built in 1956 to transport coal gas from gasifiers at Morwell in the Latrobe Valley, to Dandenong (Melbourne). The design standard of this pipeline are not well known, but the pipeline remains a part of the Victorian Gas Network.

The first "modern" pipelines were the Moonie-Brisbane oil pipeline (1964), the Savage River magnetite slurry pipeline (1965) and the Roma-Brisbane gas pipeline (1969), the Moomba-Adelaide (1969), Dongara-Pinjarra (1972), Longford-Melbourne (1971) and Moomba-Sydney (1976) pipelines. There were also a number of liquids and gas pipelines constructed in Victoria, in the late 1960s and early 1970s.

The early pipelines were designed to overseas standards, usually ASME B31.4 (liquids) and ASME B31.8 (gas), but the development of major natural gas pipelines provided an impetus for an Australian standard for gas and liquid petroleum pipelines. (See page Other Related Pipeline Standards ).

The first Australian standard for pipelines was CB 28, released in 1972. This standard was based on and largely replicated ASME B31.8.

A new revision of the gas pipeline standard was released in 1975 and designated as AS 1697. It was further revised in 1979 and 1981. Again this was largely a clone of ASME B31.8.

The year 1976 saw AS 1958, a submarine pipeline standard, developed. In 1977 a petroleum liquids pipeline standard, AS 2018, was published together with AS 1978, the first standard for field pressure testing of pipelines. AS 1958 and AS 2018 were also revised in 1981.

Up to this point Australian pipeline standards had reflected the approaches adopted in ASME and British standards. Pipelines were largely owned by the public sector. They were expensive having used imported technology, heavily supported by international engineering and construction companies.

Gas resources in Australia are typically distant from load (usage) centers. The loads were (and still are by world standards) small and the gas value is relatively low. The land between the gas resource and the load center is generally sparsely populated. These factors combine to make it difficult to justify development of gas transmission pipelines unless the capital cost can be amortized over a long project life. It was this fact that led the Australian pipeline industry to depart from "traditional" North American and European pipeline design approaches.

To reduce capital costs, the Australian industry adopted higher strength line pipe steels (and reduced wall thickness) and increased operating pressures (initially 7 MPa, then 10.2 MPa, and 15.3MPa) to increase the gas quantity transported per unit of steel. In those days, up until the early 2010s, Australia had local steel making, pipe making, and pipe coating facilities, which could respond to the local needs. These manufacturing entities shut down in around 2015.

Combined with newly developed pipe coatings, joint coatings and construction methods, they formed the basis for departure of the Australian Stand from the North American model, and the need for development of additional standards relevant to Australian conditions.

A new Standard, AS 2885, was published in 1987. While still looking much like the American Standard, AS 2885 introduced significant departures from the previous documents including:

  • Application to transmission pipelines only (pressures greater than 1,050 kPa)
  • Application to onshore gas and liquid hydrocarbons
  • Definition of a single design factor for determining the pressure design thickness of the pipe
  • Definition of a third party protection factor (to recognise the purpose of the mandatory design factors that the earlier standards applied to class locations other than broad rural).
  • The result was that more understanding and thought was required in both the development and application of the new Standard.

During the 1990s, AS2885 went through a range of developments, which saw the Standard separated into several parts. AS 2885.2 covering welding was issued in 1995, AS 2885.1 covering Design and Construction and AS 2885.3 covering Operations and Maintenance were issued in 1997.

In 2002, AS 1978 was withdrawn, revised and re-published AS 2885.5 (Field pressure testing). After several attempts to revise the old AS 1958 (Submarine Pipelines) it was decided to withdraw the Standard an replace it with AS 2885.4 (Offshore Pipelines) in 2003. Part 4 comprises DNVGL's offshore pipeline standard ST-F101 along with some uniquely Australian requirements.

The are a number of associated standards (also part of ME-038's portfolio):

  • AS 1518 Extruded HDPE Coating
  • AS 3862 Fusion Bond Epoxy Coating
  • AS 4822 Field Joint Coating

In 2008, AS 2885.0 was introduced to collect the foundational principles into one place, and provide an overarching document that ties all of the parts together.

The scope of AS 2885 is restricted to the pipeline (significantly because of the emphasis on thin walled pipe). Consequently, it has nominated that connected station piping be designed to an appropriate pressure piping standard such as AS 4041 or B31.3.

In the late 1990s and through the 2000s, developments have focused on increasing the economic efficiency of pipelines through allowing MAOP at a design factor of 80% of specified minimum yield stress (SMYS) and flange rating at and above Class 900, so long as it is demonstrably safe to do so.

Part 2 (Welding) has incorporated the most recent research on hydrogen assisted cold cracking (HACC), use of automatic welding processes, and ultrasonic non-destructive testing.

The Australian Standard AS 2885 is characterised by a set of principles that add to its uniqueness:

  • Ensuring the protection of the general public, pipeline operating personnel and the environment
  • Explicitly recognising that continuity of supply is an important secondary community safety issue
  • Requiring suitably qualified, experienced and trained people who take responsibility for their actions in writing
  • Designing against actual threats and failure modes
  • Auditing design and operations processes
  • Ensuring transparency, repeatability and traceability

The suite of AS 2885 Standards is developed and reviewed by a committee system consisting of an overseeing committee (ME-038) and a sub-committee for each part. The Main Committee comprises representatives of the industry, the peak body organisations of associated industries and industry technical regulators. Typically the subcommittees comprise people who are selected for their experience and expertise rather than representing any particular viewpoint:

  • Pipeline owners
  • Engineers
  • Constructors
  • Suppliers
  • State technical regulators
  • Independent technical specialists

This broad and inclusive group promotes national acceptance and adoption of the Standard and minimises the risk of different regulatory regimes in each state. It also brings a range of expertise to producing a strong and balanced standard.

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