Mackley made an important contribution to a challenging engineering project to replace a 4.5km section of pipeline running from under the North Sea up to the North Lincolnshire shoreline.
The Tetney Pipeline Replacement Project was carried out for the energy manufacturing and logistics company Phillips 66, which has operated in the Humber region for decades. The company’s operations there include the Humber Refinery, the Tetney Oil Terminal and the pipeline that connects the terminal to the refinery.
Phillips 66 also manages the Tetney Monobuoy which is used for tankers to offload crude oil down to the 8km subsea pipeline that takes it to the oil terminal.
In May 2015, Phillips 66 contracted Van Oord Offshore to replace a 4.5km section of this pipeline, and in turn Van Oord sub contracted part of the works to Mackley.
John Tharme, Mackley Contracts Manager, said: “We were sub-contracted to construct two cofferdams, one 10m x 5m and the other 110m x 5m, using 15.5m long piles.
“We also had to install the mooring tube piles at 18m, along with 32 launchway tube piles to take the new pipe from the pipe barge.”
With land access to the site not permitted, all plant and materials for the Mackley element of the works had to be transported by barge from Grimsby dock to the beach.
John Tharme continued: “We deployed just four Mackley team members for the project, led by Allen Cole who acted as one of Van Oord’s site superintendents, supervising the overall beach works. At the same time I was seconded to Van Oord to undertake the role of Works Manager on the beach alongside one of Van Oord’s Works Managers.
“We assisted with all aspects of the operation on the beach – including pulling, swinging and burying the new pipe – by supplying three 50t, 70t, and 160t crawler cranes, along with various excavators, dump trucks and bull dozers.”
As the new pipe was laid on the same line as the pipeline, the connection and re-commissioning date of 12 July could not be altered; oil tankers were moored offshore ready to unload their cargo on that date.
From the handover of the old pipe to handing back, the project team had 56 days and the works were undertaken 24/7, working every available tide in order to ensure the critical deadline was met.
Click here to see a selection of project photos.
7 March 2016
