New seals help Trelleborg expand market presence

FORT WAYNE, Ind.—Trelleborg Sealing Solutions recently has made major inroads in the oil and gas market, especially in the development of low compression set elastomer seals that can withstand hotter temperatures and higher pressure.

A business unit of Trelleborg A.B., the firm recently determined the need for new and better seals with longer lifetimes of service in harsh environments within the oil and gas sector, principally because many of the materials currently being used were being pushed to and beyond their limits.

That set the company on a course to develop more elastomers with an improved compression set in order to extend the seals' performance capabilities in the applications.

"New ingredients are always coming onto the market—such as curing agents, accelerators, antioxidants—and our material development is continuous," said Andrew Longdon, technical manager for Soihull, England-based Trelleborg Sealing Solutions U.K.

Trelleborg operates in a variety of market segments, he said, and it works hard to understand in which directions they are moving "to ensure we develop materials that our customers will find most advantageous to their equipment and processes."

Longdon said the company's new formulations are needed to assist operators in getting the maximum performance out of their machinery to gain greater yield and profitability in the oil and gas market.

By expanding the capabilities of the seal materials and seals themselves, the company hopes to help its customers in producing equipment with market leading capabilities,

Compression set is a key parameter for elastomer seals, according to Longdon. It essentially defines how much internal force remains inside the elastomer—or, putting it another way, how much stress in the compressed materials relaxes over time, he said.

"This, in turn, determines how well the seal will function when the energizing pressure is released, and that internal stress is key to achieving a tight seal," he added.

By improving the compression set, he said Trelleborg can extend the endurance capabilities of an elastomer, especially when subjected to higher temperatures where stress relaxation tends to occur more quickly.

Longdon said that allows the company's seals to be used in equipment for longer periods of time and at higher pressures, and can create extended periods between the overhaul or refurbishment of machinery. That's especially the case in the oil and gas industry.

Materials produced by Trelleborg Sealing Solutions, which is headquartered in Fort Wayne, can be used for straightforward O-rings, "either as individual sealing elements or where they are used as energizers for our Turcon slipper seals such as Double Deltas or Glyd Rings, in addition to more specialist types such as T seals, Wedgpaks and V stacks," he said.

It often takes numerous months to develop a new material for the marketplace, from the initial formulation through molding trials and in-house testing against typical material data sheet properties, Longdon said. The materials then go through rigorous in-field trials with selected and monitored applications.

He pointed out that some testing can be artificially accelerated, "but when it comes to long-term compression set, for example, there is no good substitute for a long-term test. For our latest compounds, this has included a 52-week compression set test."

Trelleborg's most recently developed materials are now available for the company's customers because they have successfully gone through the needed in-house evaluations.

Other materials still are going through an extensive development period, he said, "and will be released in a controlled manner until such time as we are confident that they can be applied more broadly by our customers."

In terms of the oil and gas market, Trelleborg Sealing Solutions' main plants are located in Tewkesbury, England; Fort Wayne; Denver; Bridgwater, England; and Helsingor, Denmark.

On a global scale, Trelleborg Sealing Solutions is a market leader in the numerous segments in which it operates, a spokesman said. Western Europe tops the list and accounts for a relatively large portion of the company's sales, coming in at about 46 percent. He added that the firm has increased its focus on emerging markets in the Americas and Asia.

The business unit operates 28 plants globally.