Update On The Development Of International Standards For Pipeline Coatings

August 2010 Vol. 237 No. 8

Vlad Popovici, Toronto, Ontario

A new international standard for pipeline concrete coatings – ISO 21809-5:2010 – Petroleum and natural gas industries – External coatings for buried or submerged pipelines used in pipeline transportation systems – Part 5: External concrete coatings – was published on March 18, 2010, by the International Organization for Standardization (ISO).

The new standard is part of process that began about 10 years ago. Confronted with multiple and often conflicting national standards and company specifications for pipeline coatings, the industry has been in contact with ISO to develop a global standardized approach to this topic. As a result, in 2001, the ISO subcommittee for pipeline transportation systems (TC67/SC2) of the materials, equipment and offshore structures for petroleum, petrochemical and natural gas industries technical committee (TC67) presented a program for developing new international standards for the main pipeline-coating categories. This program was developed after discussions with the interested stakeholders from the pipeline industry.

New Family Of International Standards
The new family of international standards is intended to create minimum standard requirements for coating raw materials, application processes, testing and inspection methods, as well as the handling and storage of coated pipes. ISO has a standing, 48-month-long development cycle that has been used for the hammering out the pipeline-coating standards.

A work group composed of interested individuals nominated by the ISO countries meets several times a year – usually two or three times – and prepares an initial draft that is then changed, based on comments and feedback from all the interested parties.

The draft goes through four main stages to get published as a new international standard: (1) the committee draft (CD), (2) draft international standard (DIS), (3) final draft international standard (FDIS) and (4) published international standard.

The work group is supported throughout the development cycle by ISO’s editorial committee (EDC) that ensures the successive draft versions and final published version are in conformance with the ISO norms.

The main categories of pipeline coatings covered by the new family of standards are fusion-bonded epoxy (FBE), 2-layer polyethylene (2LPE), 3-layer polyethylene and polypropylene (3LPE/PP), concrete coatings and field joint coatings. The standards for each of these categories are in different stages of development.

The FBE coatings standard – ISO 21809-2:2007 – Petroleum and natural gas industries – External coatings for buried or submerged pipelines used in pipeline transportation systems – Part 2: Fusion-bonded epoxy coatings – was published in 2007, but ISO decided in April 2010 to change the title of the standard to single layer fusion-bonded epoxy coatings and to revise the standard to include single-layer high temperature FBE coatings in its scope.

The field joint coatings standard – ISO 21809-3:2008 – Petroleum and natural gas industries – External coatings for buried or submerged pipelines used in pipeline transportation systems – Part 3: Field joint coatings – was published by ISO in December 2008 and has already been re-opened for an amendment that is in the committee draft stage.

The 2LPE coating standard – ISO 21809-4:2009 – Petroleum and natural gas industries – External coatings for buried or submerged pipelines used in pipeline transportation systems – Part 4: Polyethylene coatings (2-layer PE) coatings – was published in November 2009.

The 3LPE/PP coating standard (ISO/DIS 21809-1) has faced challenges in its development, as the different involved stakeholders – raw material producers, coating applicators, and pipeline operators – could not agree on some high-profile topics, such as the types of coatings covered by the standard. After several rounds of negative votes from the ISO countries, the standard is still in DIS stage.

The Concrete Coatings Standard
Work on the concrete coating standard started in 2005 and eight work group meetings were held during 2005-2009 involving all the main categories of interested stakeholders – engineering companies, coating raw material producers, concrete coating applicators, pipeline operators and academia. As a sign of the consensus-building approach used by the work group, the final draft of the concrete-coating standard received 95% positive votes for publication in the beginning of 2010.

The new concrete coatings standard is a welcome addition to a coating application that was previously covered mainly by company specifications. It creates for the first time a framework that can be used by the industry anywhere in the world to guarantee a minimum level of quality for raw materials, concrete mix, application process, testing and inspection, as well as repairs, storage and handling.

On the raw materials side, the standard opens the door to materials that have a proven track record in the construction industry, but are new to the pipeline coating industry. These new materials – usually industrial byproducts – can either partially replace Portland cement, such as the supplementary cementitious materials (or SCMs), including ground granulated blast furnace slag or silica fume, or become partial substitutes for the natural heavy aggregates used in concrete coatings, such as different types of heavy slags from various industrial processes. These new materials allow concrete coatings to become more sustainable, by reducing the usage of Portland cement – the manufacture of which comes with significant greenhouse gas emissions attached – reducing coating project costs and offering a new beneficial application to the manufacturers of these byproducts.

Further efforts toward more sustainable coatings are made by the standard through the creation of a regulated framework for recycling concrete as an aggregate in concrete coatings and re-using reclaimed concrete in coatings. The standard covers all the current concrete-coating processes – side-wrap (or compression wrap) process, concrete spraying (or impingement), form (or pour) process and slip-forming process, all of them using primary steel reinforcement through a galvanized steel mesh or a rebar cage. It defines the requirements for the pipe cutback area, steel reinforcement positioning, anode installation and acceptable curing methods.

Attention is paid to pre-qualification and production quality testing and inspection, with testing methods being thoroughly described or referenced from external sources. Finally, separate sections are dedicated to the repairs of concrete-coating damaged areas, as well as storage, handling and administrative aspects such as markings, test reports and certificates of compliance.

An Ongoing Development Effort
Developing new standards for the pipeline coatings has – as is the case for standards in other sectors – specific challenges. The standards have to strike the right balance between being prescriptive – defining strict requirements for raw materials, application processes, etc, that have to be applied ad litteram (to the letter; exactly) – and performance-oriented, namely focus on requiring a certain level of technical performance without strictly limiting the means of getting there, so that the door stays open to innovation in the sector – such as new materials and processes.

Another often-discussed topic is the striving to avoid creating new “company specification” type regulations under the ISO logo and instead developing real international standards that are general enough that they do not restrict competition or create dominant positions for certain companies, while ensuring that a minimum level of material and process quality is enforced.

Finally, ISO work groups have a very diverse composition and thus have to find the optimal compromise among the different interests represented – raw material suppliers, coating applicators, or pipeline operators. A consensus-building approach or at least an approach seeking compromises that minimizes the differences, will ensure that a new international standard will be used by the targeted industry.

Insulated bends

What Is Coming?
The efforts for developing new international standards for pipeline coatings are bound to continue over the next couple of years. As mentioned, the FBE coatings standard will be revised before the end of 2012 to include single-layer, high-temperature FBE coatings.

A proposal for starting work on a new multilayer FBE coatings standard was approved by ISO in April 2010 and will be developed by the newly created work group WG14-6. If the 48-month ISO development track is respected, the standard could be published as early as 2014.

Work continues on an amendment to the field joint-coating standard, as well as on the 3LPE/PP standard draft.

Finally, a new standard covering the wet insulation coating systems is being developed by a different work group (WG 19) of the same pipeline transportation systems technical subcommittee (TC67/SC2). The new proposed insulation coatings standard – ISO/CD 12736 Petroleum and natural gas industries – Wet thermal insulation coatings for pipelines, flow lines, equipment and subsea structures – has just passed the committee draft stage and is now moving into the draft international standard (DIS) stage.

Vlad Popovici is a marketing and sales manager at Bredero Shaw, a division of a Canadian energy services company with global business coverage. He manages multiple economic and strategic assessments of pipeline projects worldwide and identifies and develops new pipeline protection concepts. He holds an MBA degree (2005) from McGill University, Montreal, Quebec, and has published technical articles and economic analyses since 1996. He can be reached at VPopovici@BrederoShaw.com.

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