Sandvik Offers Deeper, More Remote Offshore Exploration with Innovation

A major technological development sees the introduction of a new hyper-duplex stainless tube material by Sandvik, which provides the ultra-high strength and corrosion resistance needed for the wellhead control systems for today's enhanced oil and gas recovery methods.

Sandvik SAF 3207 HD has been developed in anticipation of demands for more remote and deeper subsea umbilicals - the electrical and hydraulic system 'lifelines' which link remote subsea wellheads to the processing platforms. Its higher yield strength withstands increased pressures, enables thinner wall umbilicals, reducing reel sizes and lowering installation costs.

The ability to withstand crevice corrosion at seawater temperature makes the new special-purpose material ideal for very deep umbilical applications in extreme conditions.

Optimizing material strength and corrosion resistance, hyper-duplex Sandvik SAF 3207 HD extends the properties of Sandvik's industry standard super-duplex grade, Sandvik SAF 2507. Use of the new grade makes it possible to develop installations and explore new fields that were previously thought to be too expensive and technologically unattainable.

Specifically designed for deep water, high temperature and extreme pressure applications, the new grade represents the natural evolution of the Sandvik duplex materials.

Its development results from years of oil and gas industry experience and Sandvik's vast and advanced metallurgical research and process development capabilities. The company has one of the largest R&D facilities in the world of steel.

Sandvik's duplex stainless steel grades for umbilicals provide a range of materials whose inherent strength means lower weight through thinner walls and the ability to support its own weight in deep water, whilst maintaining excellent corrosion resistance, even at extreme water temperatures.

Super-duplex grade Sandvik SAF 2507, the established workhorse of the oil and gas industry, has all round excellent corrosion properties, high strength - a tensile strength of 800 to 1100 MPa - and can operate at a maximum water temperature of 65degreesC (150degreesF). By comparison, hyper-duplex Sandvik SAF 3207 HD has extremely high strength - a tensile strength of 980 to 1180 MPa and takes the maximum operating temperature up to 90ºC (194degreesF).

It has good weldability using welding procedures similar to those used for super-duplex, with the welded joint having excellent toughness, strength and corrosion resistance.

Stainless steel umbilical tubing from Sandvik is available in a range of sizes from 11mm up to 89mm outside diameter.