Innovations in tubing

Paul Boughton

Meeting the evolving demands of precision tubing for the oil and gas industry. By Brian Mercer

The history of the oil and gas industry is one of constant evolution. The sector has long demanded – and continues to demand – new technological solutions to new problems. The oil and gas industry has seen a drive to exploit fields in increasingly hostile environments, from the first subsea drilling in the 1970s through to the deepwater challenges of the present day, where seawater and sour crude oil can make extraction particularly hazardous. Moreover, with the recent slump in oil prices, operators are looking not only for solutions to new technological problems but also products that deliver the most cost-effective use of resources.

Escalating requirements

How can equipment suppliers, charged with the responsibility for developing and delivering solutions to these ever-escalating requirements, succeed in meeting such challenges consistently? For Fine Tubes and Superior Tube, manufacturers of precision tubing for the most critical applications, the answer lies in having the experience to innovate.

From the early days of North Sea oil production, the sister companies have been at the forefront of meeting the needs of their customers, manufacturing corrosion-resistant tubing with tight tolerances that minimise the risk of production downtime resulting from the need to install replacements. In addition to North Sea projects, Fine Tubes has recently supplied specialist tubing for the development of fields in Norway, Nigeria, Australia and a number of the GCC countries in the Middle East.

Key approaches

One of the key approaches to meeting operational requirements has been the use of exotic alloys, including: austenitic, super austenitic, duplex and super duplex stainless steels; titanium grades; and nickel alloys.

The aim is to produce tubes that can withstand operating pressures of up to 60,000psi. Both Fine Tubes and Superior Tube regularly supply precision tubing in stainless steels 904L (UNS N08904) and 6Moly (UNS S31254), as well as nickel alloy 625 (UNS N06625) and alloy 825 (UNS N08825) for global offshore and onshore projects.

With tensile strengths greater than 220ksi (1,515 MPa), the tubing can be manufactured in sizes from 1.6mm (0.063in) OD up to 63mm (2.475in) OD.

Seamless, straight length, precision tubing is produced for instrumentation equipment as well as onshore control panels, topside processing facilities, and offshore subsea manifolds and templates up to 2,000m under the sea.

Coiled tubing is produced for downhole hydraulic control and chemical injection lines, subsea hydraulic power and chemical injection lines, and smoothbore control lines used in fibre optic applications.

Fine Tubes is a member of the highly influential Advanced Well Equipments Standardization Group (AWES), helping to set industry standards. For example, the company has been a major contributor to the development of a new recommended practice for the design, manufacture and testing of tubing encased conductor (TEC) cables and control lines.

TEC is an armoured electrical cable used to provide power to, and/or return a signal from a downhole tool. It is typically encased in a longitudinally seam-welded metallic tube in a non-annealed (cold-worked) condition. The new standard will be published in August 2015 and is another demonstration of Fine Tubes’ commitment to excellence in critical application design.

Continuing to innovate in the oil and gas arena, development plans for both tube mills include:

An evolution of the alloy 825 grade for control line tubing with higher corrosion resistance and mechanical properties

New capabilities in 1/8˝ fibre armouring for distributed temperature sensing (DTS) and distributed acoustic sensing (DAS) systems for monitoring shale gas applications, complementing the portfolio of ¼˝ tubing encased conductor (TEC) and tube encased fibre (TEF) cables.

Continued development of up to ½˝ diameter armouring for steam-assisted gravity drainage (SAGD) heater cables and possible ‘hybrid’ lines containing both copper signal and fibre optic components.

Since being acquired by Ametek, both tube mills formed a partnership that enables them to optimise the manufacturing locations for their range of high-performance tubing products and significantly reduce lead times in key areas.

“Our engineers work closely with major oil and gas companies across the globe to develop specifications for innovative new products and help customers solve their technical challenges. We encourage customers to reach out with their needs, wherever in the world precision tubing is required,” concludes Mark Ayers, director, Oil & Gas Products.

For more information at www.engineerlive.com/iog

Brian Mercer is with Fine Tubes in the UK and Superior Tube in the USA.

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