Pipeline Technique Ltd headquartered in Huntly, Scotland is a pipeline construction service company specialising in the niche area of automatic pipeline welding in the oil and gas sector. Welding is the single most critical activity in the construction of a pipeline and with the move in to ever deeper waters offshore there are continually increasing demands being placed on the quality of the finished weld. Over the years Pipeline Technique Ltd has developed welding procedures and carried out welding on some of the largest, deepest and most technically demanding pipeline systems ever installed. The company commenced trading in late 1999 following a review of current working practices, procedures and welding methods in the pipeline construction industry, and an evaluation of the industries future needs. This review and evaluation highlighted the potential for the introduction of automatic welding techniques into a number of areas with the potential of providing significant added value to the client. Growth of the company has proven to be rapid with employee numbers moving from an initial 15 in 1999 to a peak level of 350 throughout the world. A US subsidiary based in Mobile, Alabama was established in 2002 to service the American market. The majority of the company’s turnover is overseas and is largely for work on pipelines being installed in ultradeep waters.
The company was established by individuals with significant experience of pipeline construction from the design stage through detail engineering and procurement to construction, installation and commissioning. Additional personnel have been recruited along the way to allow the company to provide a full range of services and to manage its business effectively and safely. These personnel, including welding engineers, project managers, human resource and QHSE managers, operations and technical support staff. We have worked hard to consistently meet the needs of our clients and in 2002 the company achieved accreditation to ISO 9000:2000 for its Business Management System and ISO 14001 for its Environmental Management System.
Key to the company’s success has been its ability to develop automatic welding procedures for pipelines and Steel Catenary Risers (SCR’s) and then provide the specialist personnel, equipment and materials required to implement these procedures on site and carry out the welding to the most stringent requirements and tightest acceptance criteria. Nearly all deepwater pipeline welds are inspected using Automated Ultrasonic Testing (AUT) which has the ability to detect weld defects of less than 1mm in size. Pipeline Technique embraced this technology a number of years ago and have the ability to use this technology to its advantage. All 22 SCR’s welded by the company to date have used this inspection method including the largest diameter (24”) and heaviest wall thickness (40mm) SCR’s ever installed.
Many articles in industry magazines, journals and the press have discussed the issues and technical challenges associated with construction of deepwater pipelines and SCR’s installed on recent projects and they have highlighted the many industry firsts achieved. Three of the largest and most technically demanding of these are the BP Mardi Gras, BP Thunder Horse and BP Atlantis projects in the Gulf of Mexico involving installation of more than 15 SCR’s ranging from 8” to 24” outside diameter, from 17mm to 40mm wall thickness and with 5 pipe-in-pipe risers. What is not widely known is that Pipeline Technique, through contracts with the offshore installation contractor and onshore double joint fabricator, have been involved at every stage of the welding of every one of these risers from weld procedure development through qualification to performance of the welding itself. By the time offshore installation is finished on these projects later this year virtually every weld in the 320Km long ultradeepwater section of the BP Mardi Gras pipeline and riser system and virtually every weld on the 65Km long ulradeepwater Thunder Horse pipeline and riser system will have been made or worked on by Pipeline Technique. On the BP Mardi Gras project Pipeline Technique worked with the installation contractor to develop automatic and semi-automatic welding procedures to double joint pipe onshore (and weld on collars), to fully automatically weld double joints in to hex joints on the deck of the J-lay vessel and to fully automatically weld the hex joints together in the vertical (2G) position in the J-lay tower. The critical path J-lay tower weld procedures were developed with very narrow gap bevels (1 degree) using dual torch welding methods which allow a 24” od x 33mm thick weld to be made in 16 minutes. The story is similar on the Thunder Horse project where procedures were developed for 8”, 10” and 12” od pipe ranging in 30 to 40mm thickness and in X65 and X70 material grades. The minimum CTOD values specified and achieved on these projects, a measure of how resistant the welds are to fatigue failure, were 0.66mm and 0.55mm respectively.
Recently, we have also completed the welding of the Kerr McGee Red Hawk, ENI K2 & Dominion Triton/Goldfinger SCR’s using manual GTAW. Contracts for this work also included provision of all related construction services e.g. AUT, field joint coating, pipe handling, pipe end dimensioning and counterboring.
Numerous other pipeline construction projects have been completed over the last 15 months including four “pipe-in-pipe” jobs totalling 67Km in length and a specialised automatic welding project on a 2” diameter by 3.8mm thick superduplex stainless steel tube.
Based on the current market outlook, forthcoming projects and the increasingly difficult technical challenges involved in welding deepwater pipelines, requiring use of Pipeline Technique’s core strength, automatic pipeline welding, we foresee challenging but rewarding times ahead.