Ship & Boat International: eNews September/October 2018
Waterjet manufacturer MJP has launched its new X Series range of jets, designed to assist small boat operators in realising significant fuel savings. The mixed-flow X Series comes in three configurations – namely, the 280X, 310X and 350X – with the common aim being a reduction in weight and power drainage for vessels sized up to 50m.
The X Series is fashioned from duplex steel, which, MJP reports, can offer twice the yield strength of similarly sized aluminium waterjets, and is intended for applications in excess of 50knots. Magnus Sörenson, MJP chief executive, says that a related advantage of incorporating this type of steel is that “operators don’t have to be too concerned about the quality of the water in which they are operating – including the presence of pebbles – as this material is rugged enough for the jet to take such conditions in its stride.”
Sörenson also likens the X Series to a “jet in the box”, given its plug-and-play capabilities and the fact that it has been developed for “one-piece skidded installation”.
All hydraulics are pre-installed, thus obviating the need for additional equipment or piping, and each jet incorporates a closed-loop steering system. Weight-wise, MJP adds, the X Series can also cut weight by up to 10% compared to axial-flow jets.The jet has been constructed with inspection hatches, to simplify inspection and maintenance procedures, and its integrated hydraulic system features separated seals for water and oil, to prevent leaks and to guard against corrosion.
Much of the X Series’ development has hinged on MJP’s research into hydrodynamics, including the tweaking of previous solutions. This has resulted in a new steering fin design and an optimised redesign of the pump’s intake geometry, to allow for enhanced performance at lower speeds, without impacting on the upper speed range. Users can also fit interceptors on either side of the jet, to generate greater lift.
MJP estimates that the X Series could also reduce power demand by 20% compared to conventional axial-flow jets. For the same amount of power, Sörenson adds, the user can wrench an additional 1-2knots from the X Series, thereby providing a welcome speed boost for small craft.
The jets in the series can be controlled either via hydromechanical controls or MJP’s JetMaster 3 electronics system. The former option is intended to appeal to those operators who prefer a simpler, hydraulics-based means of control, rather than having to deal with electronic controls.
The first member of the X Series to have been commercially launched is the 310X model, which is rated 700kW, and which was profiled at this year’s Seawork and SMM events. This will be followed soon by the 580kW 280X and, finally, the 900kW 350X.