The Engineering Business (EB) has been contracted to use this knowledge and experience to design and build the ultimate plough system for Saipem UK Ltd.
As an integral part of a new build trenching support vessel, the system will allow Saipem to offer its customers effective trenching of pipelines up to 1.55m in diameter, up to 2.5m below the seabed, in water depths of up to 1000m. The system comprises two ploughs - PL3 the trenching plough and BPL3 the back fill plough.
"We're truly passionate about ploughs," says EB's managing director, Dr Tony Trapp. "And, we are genuinely excited to have been challenged to deliver a game changing plough system. Our design will focus on increasing levels of performance, productivity, reliability and safety and will allow Saipem to trench the largest and longest subsea pipelines."
The new trenching support vessel being built by Aker can deliver a tow force of 400tonnes and will be the highest performance vessel in her class. It has sufficient deck space to accommodate both PL3 and BPL3 simultaneously and it is therefore possible to switch between ploughs at sea.
"We were asked to design a trenching spread matched to the exceptional capabilities of this vessel" explains Mike Crosby, Senior Engineer. "As such, the new PL3 plough will weigh in the region of 180 tonnes, is 22m long, has 100t capacity pipe handling equipment front and back, and can create a 2.5m deep trench. The control system will be built into the ship bridge module and this together with the use of buoyant control umbilical will greatly increase productivity in comparison to previous spreads."
BPL3 is unlike any previous backfill plough - aimed at reducing the risk of damage to the trenched pipeline, its front skids run outside the trench. As a result it has been designed to fold into itself, rather like a spider, for launch and recovery. Its design also means it is possible to launch the plough in the correct orientation which will save time during deployment.
"Having provided interface information to allow the design of the vessel to progress, we are now into the detailed design phase of the project, working closely with Saipem at every stage," explains Mike Crosby.
The build of both PL3 and BPL3 will take place at EB's Hadrian Riverside facility, with maximum advantage taken of the proven North East of England supply chain. Delivery is due late in 2008 and EB's quayside facilities will allow the equipment to be mobilised directly onto the vessel.