Excellent interaction between Claxton and Subsea 7 ensures success of Centralizer project

Subsea 7 approached Claxton when it had the job of retrofitting centralisers in a number of subsea conductor guides beneath two platforms for an operator in the Norwegian sector of the North Sea. The project was in response to various challenges connected with the inaccurate positioning or slippage of the original centralisers.

Engineers from Claxton and Subsea 7 together examined the specific practical challenges posed by the project. This led to Claxton modifying an existing centraliser design to produce a slim, lightweight, three-piece centraliser capable of being wrapped around the conductor and slipped down into the guide. The two parties continued to work closely to test the new design thoroughly onshore, develop installation procedures and plan the necessary diving operations.

Claxton was initially asked to supply 10 of the centralisers, all for 26-in. conductors: eight suitable for fitting in 36.5-in. guides and two for 34-in. guides. Later, Subsea 7 added one more of the latter design to the order and asked for this to be supplied within two weeks. Claxton formally received the request on 15 September 2010 and delivered the centraliser 11 days later.

Subsea 7 reports that the work offshore to install the centralisers went well and was devoid of incident, just reward perhaps for the joint efforts of the two companies in the lead-up to the project.

Claxton project engineer Ann Vicens Morton is certain this was the case: that the success of this project and others like it was the result of the excellent interaction between supplier and client. “Collaboration is always the key,” she says. “There has to be a willingness to discuss all aspects of the job and to work together to devise a practical, installer-friendly solution to the challenges expected offshore. Solid preparation up front has the power to save considerable time and, therefore, money during the offshore operation.”

It was agreed all round that the success of the project was the result of excellent interaction between Claxton and the client.