Fuel sealing systems testing

Evolving certification requirements impact oilfield service companies’ choice in material suppliers.

By Eric Bucci, Trelleborg Sealing Solutions

Oilfield service companies (OFS), the backbone of the oil and gas industry, are closely following the movements of such customers as Halliburton, Schlumberger, Cameron International, FMC Technologies, and Baker Hughes. These customers are also leveraging important trends for their customers simply because they have to in order to maintain their competitive edge.

One key trend that most oil and gas companies seem to be doing a pretty good job at is limiting their exposure to any one region by diversifying into multiple international markets. Experts point to how they have been counting on overseas business due to the better market conditions than in North America in the last few years. For instance, Schlumberger recently set up a joint venture with Cameron International under the name OneSubsea to capitalize on the growing offshore oil and gas market. This has translated to large OFS providers needing to maintain their concentration on those rising offshore oilfield projects. It also means that, as part of their global business model, the oilfield service organizations have unequivocally chosen to favor seal and material suppliers that can support them both globally and strategically.

From a strategic standpoint, it’s advantageous to partner with an oilfield material supplier that has long been committed to the provision of sealing solutions for the upstream and downstream oil and gas industries. Another strategic component of particular interest to OFS companies is their seal materials suppliers’ investment in R&D and in having facilities and analytical laboratories that are equipped with state of the art equipment and technology.

As the technology employed to exploit natural resources has developed, so have the materials and products likewise evolved in order to provide essential reliability under increasing arduous operating conditions. Large-diameter seals are often used for floating production, storage and offloading (FPSO) valve applications, downloadable tool applications, and just about every aspect of oilfield applications. This would include seismic guns, drilling motors, skidding systems, valves, firefighting vessels and more.

Safety is what has ultimately led to the push for governing bodies to instill standards. The leading oil and gas suppliers that are primarily supporting the large OSF firms know the importance of attaining the right certifications.

Oilfield service companies recognize the various governing bodies serving the oil and gas industry as NORSOK, American Petroleum Institute (API), and National Association of Corrosion Engineers (NACE). Each of these governing bodies have worked closely with seal suppliers and have played an instrumental role in releasing newer standards on how a fuel material should act and work in an oilfield environment. For instance, to attain certain certifications, these governing bodies require the supplier to submit fuel test examples to run through an independent, third party lab to ensure the supplier is in compliance with industry certifications.

From our experience in achieving compliance, we can share that these tests are expensive and very thorough. Not every fuel material company can afford to undergo this certification process. However, the need for suppliers to undergo the certification process is considered important to the industry and is mainly driven by the growing need for increased safety in the oilfield. Suppliers need to ensure that their seals will meet compatibility and performance requirements.

API maintains more than 500 documents that apply to many segments of the oil and gas industry, from drill bits to environmental protection. API is the perennial governing body that relates to the certification of a completed oilfield piece of equipment such as a gate valve. For instance, the entire gate valve will be tested and approved by API and seals will be part of the gate valve’s certification.

Recently API has stipulated that sealing systems testing requirements include a fire test for end connections and for drilling well control systems; verification testing of wellhead surface safety valves and underwater safety valves for offshore services; adherence to certain specifications for sucker rods, polished rods, clamps and liners, couplings, sinker bars, stuffing boxes, and pumping tees; and the isolation of potential flow zones during well construction.

Its governing counterpart, NACE, uncovered that with seal procurement, there have been multiple cases of failures caused by permanent compression sets of o-rings and cracked energizing springs, which is why there is such a need for certification for seal suppliers. NACE developed test protocols aimed at defining elastomeric seal materials that can avoid damage during decompression in high-pressure gas duty.

The oil and gas industry has the most stringent applications, chemicals, pressures, and temperatures. While friction is a secondary concern, the primary concern in the use of fuel seals is just how the seals will react over time when exposed to severe chemicals. Extending the long-term life of the seals is one priority but really ensuring safety is paramount especially considering that people can die if the seals fail.

In summary, oil and gas suppliers are starting to comprehend the importance of adhering to standards and working with suppliers that have global exposure and experience working with OFS companies to meet their unique engineering and design needs. Intimate knowledge of the characteristics of different elastomers is vital when designing seals, especially since certifications do evolve to align with the changes within the industry.