5.3 - Seabed Tractors and Trenchers

A seabed tractor or trencher may be configured to lay and bury a cable. These vehicles are tracked crawlers, built to be controlled from the vessel, with operators ‘driving’ the unit as if they were on board. These units usually move slowly, depending on soil conditions. In some cases an ROV is deployed independently, to record progress and performance.

Trenchers for pipeline burial are much larger and heavier. The trencher is lowered onto the seabed over the pipeline and the DP control system can set the centre-of-rotation of the trencher.

Sketch 5.5 - trenching operation