Record length liner insertion hastens North Sea Triton pipelay

April 20, 2012
Swagelining says it has achieved a record-length single insertion pull of 1,500 m (4,921 ft) while installing polymer liners in the UK North Sea.

Offshore staff

ABERDEEN, UK – Swagelining says it has achieved a record-length single insertion pull of 1,500 m (4,921 ft) while installing polymer liners in the UK North Sea.

The liners were inserted into pre-constructed steel subsea pipeline spools for the Triton field.

Subsea 7 commissioned the company to design and install a polymer lining solution for 25 km (15.5 mi) of 10-in. (25-cm) water injection pipeline, to be installed from the reel-lay vesselSeven Navica following fabrication at Subsea 7’s Vigra spool base near Alesund, Norway.

The spoolbase extends 2,037 m (6,683 ft) from the seaward end of the stalks to a purpose-built deepwater quay.

Stephen Barnes, managing director of Swagelining, said modifications to the equipment spread, confirmed by a pre-qualification test program, allowed towing loads to be reduced. This in turn allowed the 1,500-m liner installation lengths to be repeatedly achieved, in turn improving construction times.

“The liner was installed quickly and efficiently into the carbon steel host pipe achieving the targeted rate of one constructed string per day. Terminations and jointing were completed using the flangeless WeldLink connector fitting, which allowed the pipeline strings to be welded and spooled onto the reel lay vessel for installation on the sea bed.”

Subsea 7 has since awarded the company two further North Sea water injection pipeline projects, both due for fabrication and installation during 2012.

4/20/2012