Many thousands of pipe-in-pipe (PIP) centralisers in Devlon polyamide materials are now installed on more than 20 offshore pipelines around the world - including deep sea fields such as Shell Nakika with 2300m (7550ft) maximum water depth in the Gulf of Mexico.
Manufactured in Scotland by engineering plastics specialist James Walker Devol, the centralisers are supplied complete with fasteners for quick and easy on-site installation at the spoolbase, where the pipeline is prepared for reeling on to the pipelay vessel.
Prior to Devol's development work on centralisers in the late 1990s, these products had traditionally been made in steel or softer plastics such as polyurethane. When the offshore environment became more demanding, the problems of low abrasion resistance, heat loss, friction and deformation had to be overcome.
This was achieved using specially formulated grades of polyamide materials, including Devlon V-API and Devlon T100 that work at high temperatures and pressures in the offshore sector and offer excellent wear resistance, low friction and low thermal conductivity.
The material grade selected for a specific project depends on the operating environment. All PIP centralisers are designed by James Walker Devol to customer specification to suit the working temperatures, depths, loads and pipeline dimensions.
James Walker SPS Ltd is based in Crew, Cheshire, UK. www.jameswalker.biz
