V-Jet system

V-Jet systems are designed for use with the SeaVator hydrodynamic excavator to improve trenching speed and excavation performance in cohesive and compacted soils.

The SeaVator and V-Jet equipment can be used to dig trenches up to 5.0m deep in single or multiple passes in suitable soils. Each system consists of a pumping spread with water suction riser, hose reel and umbilicals, SeaVator manifold and jetting pipe assemblies and a range of jetting nozzles to suit different soil strengths and seabed conditions.

Three jetting systems can be configured (mono, dual and multi jets) and various power levels up to 5000hp are available to allow operations in the widest possible range of activities. The standard 600hp Dual V-Jet system is designed to suit most trenching applications in sand and weak clay soils up to 25kPa and pipeline diameters in the range 0.25 to 1.0m. Single pass trench depth can be varied between 0.25 and 2.0m.  Higher power configurations allow for faster progress in more cohesive soils or when working with larger product dimensions.

Where it is difficult to recover redundant objects such as concrete weights and pipeline supports or environmentally safe debris (due for instance to awkward shape, lack of lift points or poor condition) sub mud line burial may be an appropriate method of disposal. The Mono-jet system (a single central vertical jet mounted under the SeaVator) is suitable for fluidising the seabed locally, allowing objects to sink below seabed level.  The Monojet was recently used to excavate 100 kPa soils for clamp access on a damaged pipeline, well beyond normal mass flow excavation limits on soil shear strength.