In an accelerating quest for new oil and gas reserves, oil companies go further and deeper into offshore basins. Today more than 60 percent of the world’s petroleum products come from offshore fields in waters as deep as 2,500 meters where the pressure exceeds 200 bars. Faced with some of the most severe subsea conditions, oil and gas companies take care to ensure nothing can go wrong.

The wellheads on the sea bottom and the drilling platform are often connected by flexible pipe. The critical core part of the pipe that carries the crude is a hose built out of profiled stainless steel strip, surrounded by layers of mild steel and insulating materials. During pipelaying and when submerged, flexible pipe needs to withstand its own tremendous weight besides the extreme pressure of the deep. Only the best of materials will do the job in the core, sourced from carefully certified producers, as a single leak means a huge setback in the highly expensive pipelaying operation or in production.

A flexible pipe cross section.
Courtesy: NKT Flexibles.

Outokumpu has proven itself for the challenge. Today, Outokumpu supplies all three manufacturers of flexible pipe: Technip of France, Wellstream of the United Kingdom, and NKT Flexibles of Denmark.

Manufacture of flexible pipe. Photo courtesy: Wellstream

One reason for Outokumpu’s heavy role in the flexible pipe industry is the company’s attested leadership in coil products in duplex grades at a time when that industry is increasingly shifting away from the previously dominant standard austenitic grades EN 1.4301 (ASTM 304) and EN 1.4404 (ASTM 316L) towards special grades in search of better corrosion resistance and strength. Outokumpu’s proprietary LDX 2101® is emerging as a serious contender to austenitics. LDX 2101® already represents approximately 10 percent of all strip supplied by Outokumpu for flexible pipe and is expanding. LDX 2101® brings the benefits of more than double the yield strength and far better corrosion resistance compared to 1.4301. As a result, manufacturers can achieve considerable weight savings.

Another reason for Outokumpu’s strength in the flexible pipe industry is the slitting capability required by the processes of the pipe manufacturers, including edges prepared according to specific needs. Furthermore, Outokumpu is an approved supplier of both standard austenitic grades and duplex grades for the offshore industry – a must for oil and gas companies.

“Our broad experience in flexible pipe, together with more than 20 years of experience in duplex grades, has evolved into an invaluable knowledge base to serve the industry,” says Mikael Paijkull from Nyby, underscoring Outokumpu’s number one position.

Contact:
Mikael Paijkull
Product Manager, Special Grades
Outokumpu, Thin Strip Nyby, Sweden
Tel. +46 16 349 368 
E-mail: mikael.paijkull()outokumpu.com

Published June 8, 2006

        
Flexible pipe on its way to offshore sites.
Photo courtesy: Wellstream