TPT July 2009

W elding: L atest D evelopments & M achinery

Ensuring girth welds are right first time

requires accurate measurement of the weld area in order to ensure zero defects and to avoid the delay and cost of a weld cut out later in the welding process. The technology can be deployed onshore and offshore at different stages of the pipe welding process. The tool can be used on corrosion-resistant alloy-lined pipe to identify sour (aggressive) ingress points, in both clad butt-weld and clad weld inlay applications. The tool can also be used to improve weld procedure development efficiency and to check the root weld and geometry before next passes are deposited. The technology provides similar uses in fatigue-sensitive applications (SCRs) where the pipe is subject to higher dynamic stresses. The system can be mounted to a purge dam, with an integrated camera for positioning and inspection. Pipe can be inspected whilst it is being spooled onto a pipe laying vessel or during stalk fabrication/tie-in. Here, the tool is retrieved using a winch and wire system, with weld positioning controlled by a camera and precision motorised system. Richard Gooch, director of technology at OMS comments: “We demonstrated the

A new internal weld inspection system has been launched that inspects the internal size and shape of girth welds on pipes destined for use in deep sea subsea oil and gas applications. The internal weld scanning tool, developed by UK-based company, Optical Metrology Services Limited (OMS), internally scans welds inside pipes – both visually and

dimensionally – enabling engineers to quickly and confidently assess the quality of the root weld. In oil and gas pipes, the quality of the root pass of a weld is critical to the structural integrity of the girth weld. Oil and gas companies therefore have stringent inspection requirements for checking welds but few tools currently exist on the market that can perform this kind of work. Welding of clad pipe is especially challenging, and

Pipechecker internal weld scanning tool from OMS

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J uly 2009

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