FlexSteel has been optimised for onshore and shallow water development. Typical applications include oil or gas gathering lines, injection lines and water or fuel transfer lines.

FlexSteel offers many advantages over carbon steel line pipe and other alternatives. Some of these include the fact that it is highly flexible and spoolable; it is steel reinforced; it has a polymer sheath and polymer liner; and that FlexSteel is factory hydro-tested to ensure product integrity and quality prior to shipment.

The FlexSteel design includes two layers of steel armour. Each of these is spirally wound in opposite directions to provide the structure for pressure containment of the conveyed fluid. A smooth internal liner of pipe grade polyethylene (PE) protects the steel from the internal fluid. Similarly, an external PE sheath protects the steel from the outside environment. The standard high-density polyethylene (HDPE) liner material provides for service temperatures from -40ºC to 60ºC.

Proven swaged end fittings, similar to those used for high pressure hoses, terminate FlexSteel. The swaging method allows quick reliable installation both in the factory and in the field. Standard swaged end fittings offer a choice of an ANSI flange or a pipe stub end for welding. The standard end fitting material is stainless steel for corrosion resistance. Midline connections can be flanged or welded, depending on customer requirements.

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Wellstream offers FlexSteel in standard diameters based on those of steel pipe, in pressure ratings that match ANSI classes.

FlexSteel pipe is designed, manufactured and tested with consideration to API 17J, and the end fitting with consideration to API 17K. While this is a new product that has some minor variations to these standards, the proven Wellstream design tools, methodologies and design factors from years of offshore experience are used to ensure the FlexSteel designs are reliable and robust.

FlexSteel is handled and installed easily as cable or plastic line pipe. It is equally suited to above ground applications, below ground installation with conventional ploughed or trenched techniques, and modern trenchless techniques such as horizontal directional drilling. FlexSteel installations are much quicker and are accomplished at a lower cost than those of steel pipe with a considerable reduction in man-power.

Also suitable for pipeline rehabilitation, unlike liners that depend on the remaining structure of the original pipe for structural integrity, FlexSteel is inherently pressure containing. For pull-in applications, the standard FlexSteel catalogue pipes are designed to fit in with the next largest steel pipe or offer the flexibility of being pulled through the same size split pipe.

Qualification and characterisation testing on FlexSteel is accomplished per the methods of API RP 17B. The steel reinforcements in the FlexSteel pipes allow hydrotesting at up to 1.5 times the design pressure.