Safety Pipe for Oil Rigs

Trelleborg AB

Trelleborg has developed a product, that can withstand a jet fire - the cause of the Piper Alpha disaster. The product is already in use on several platforms, primarily in the North Sea.

It was 9:31 p.m. on July 6, 1988 when the alarm sounded. The Piper Alpha oil platform off the British coast was burning. The fire was intensive and spread rapidly. Within seconds, the entire platform was ablaze and had split in two. A total of 167 persons lost their lives. The cause of the fire was a leak in a pipe that started what is called a jet fire. This is a very explosive fire that can reach a temperature of 1,300°C within a few seconds. The flame, which was as hot as a welding arc, quickly burned out the water circulation system, mak-ing it impossible to save the platform.

Since this accident, Trelleborg has developed a product, Elastopipe, that can withstand a jet fire, while offer-ing a number of other unique benefits. The product is already being used on several platforms, primarily in the North Sea. The product was developed by Trelleborg Viking A/S located in Mjondalen, Norway, about -50 kilometers west of Oslo. Development manager Kyrre Sjotun has lived with the devel-opment of Elastopipe for just over ten years. "In 1990, we started a project together with several other stakeholders to develop a non-combustible material that would also be toxin-free and not produce any smoke," relates Kyrre. "Six years later, we had developed the basic principles for the material used to produce Elastopipe, was subsequently improved and continues to be refined."

Norwegian government financing

The principal financiers of the project are the Norwegian gov-ernment and the Statoil, Hydro, BP/Amcon and Phillips oil companies. With so many par-ticipants, each with different priorities, development work needed to take many different requirements and objectives into consideration. The initial requirement, which was that the material should be able to with-stand a jet fire, was supplement-ed by a number of others along the way. However, Elastopipe, Kyrre Sjotun and Trelleborg Viking succeeded in meeting all of these requirements.

To rationalize development work, Trelleborg Viking built a test rig in Norway that is con-sidered one of the most advanced of its kind in the world. Several hundred tests have been conducted on this rig, which remains in use for contin-uous testing each week, mean-ing that it will play a key role in ongoing development. The rig allows many different possible, as well as completely impossi-ble, scenarios to be simulated. Exactly the desired combination of flame speed, temperature and heat flux parameters can be cre-ated for testing.

Must withstand temperatures of 1,400°C

"Through testing, we have determined that the material should withstand a gas flame with an initial speed of 270 meters per second, an entry speed in the material of 110 meters per second and a temper-ature of 1,400° C," says Kyrre Sjotun. "Naturally, we are not willing to reveal the secret behind Elastopipe's unique characteris-tics, but I can say that an impor-tant property is that the materi-al `sweats,' which means that it will not start burning," contin-ues Sjotun.

To date, some NOK 7 million in development costs- has been invested annually. These costs are shared by the project spon-sors, comprising the Norwegian government and a number of oil companies. Continued develop-ment is not expected to be as costly and will focus more on handling other derivatives, such as gas and oil, and possibly being able to offer a material in other colors for customers who wish to customize their equip-ment using their own color schemes.

Simpler, more efficient installation

"Elastopipe is based on synthet-ic rubber. Basically, it is a method for transporting water, a pipe, that at the same time must meet a number of differ-ent and very stringent require-ments, of which the most fun-damental is that it must with-stand the special form of fire called jet fire. Today the prod-uct can replace the steel and titanium pipes that are used on many of the world's oil plat-forms. We can now compete with all the materials and dimensions used in this mar-ket," notes Kyrre Sjotun.

"Another very important competitive advantage of Elastopipe is that installation is simpler than for competing materials," continues Sjotun. "It is faster, in part because the pipe is easy to bend, but also because it is not necessary to stop pro-duction while installation is in progress, since no `hot work,' such as welding, is required."

Significant potential in a fast-growing market

Erik Leknes, president of Trelleborg Viking is very opti-mistic about Elasto-pipe's prospects. "It's always risky to make promises, but we see tremen-dous potential for Elastopipe, which is clearly our company's most important product right now," says Leknes. "We also already see that the product's unique properties mean that it can play an important role and has a significant competitive advantage."

How will the product be developed in the future?

"The basic application will remain the same, meaning transporting water even when a fire as violent as a jet fire erupts. One possible line of develop-ment that I foresee is that we may be able to develop a material that is thinner. We are also working to develop additional dimensions for the pipe. Currently, we offer dimensions from one to six inches. Our ambition develop an eight-inch pipe," says Erik Leknes.

Safety standards dri-ve the market

Customers are primarily major oil companies, including Statoil, Hydro, BP and Phillips but also companies, such as Kvaerner, Brown&Root and ABB, which provide mainte-nance for various types of deep--sea platforms. Customer-s are distributed geographically according to how high safety requirements are in their particular environments. Today's cus-tomers are thus found in North Sea, where safety stan-dards are high, followed by Australia, Great Britain and the Gulf, or Mexico, in that order.

Elastopipe is currently used on some 20 oil platforms primarily in the North Sea. These platforms are located in fields well known in the industry, such as Statfjorfelt and Elkofisk, the oil field where Norway's oil adventure began.