The KRANSKAN™ indicator is a dedicated safety device developed by Hook Marine to provide warning of hazardous conditions during marine crane operations.
KRANSKAN – Hook Marine recognised the need for such a device, given that many boats are not fitted with effective inclinometers to warn of the approach of angles of heel at which the cargo might shift, or capsize occur. Workboats are frequently in their most unstable condition when the deck crane is lifting a heavy load.
Load indicators should also be fitted to protect the cranes and their mountings from overload. If a winch is fitted, full account must be taken of the change in weight if lifting a submerged load.
The KRANSKAN™ indicator measures these two parameters, giving an audible and visible indication of the safety margins at the crane controls. Coloured lights and a two-tone alarm on the KRANSKAN™ indicator warn the crane operator of approach to a pre-determined maximum load moment for the crane or maximum angle of heel for the boat.
The crane operator is therefore fully informed of the twin hazards of overload and over-heel as the lift progresses.
KRANSKAN ™ indicator variants are available for crane applications where the operator sits on the crane structure, allowing continuous 360° rotation.
Fitting a Kranskan indicator allows for the full load capacity of the crane to be used when lifting over the bow or stern of the vessel while heel angle warning restricts the load to be lifted over the side of the vessel. There is no requirement to de-rate the crane for side lifts by reducing the hydraulic pressure.
The Kranskan™ with Control Function
As an extra safety measure, the Kranskan™ indicator can be provided with a cut-out feature. When the crane reaches the maximum load moment, or when the vessel reaches the maximum permitted angle of heel, a signal is transmitted to the crane which prevents any further crane extension.
The Kranskan™ indicator MK5 RF variant
The MK5 RF variant has been designed for marine cranes with continuous slewing where the operator sits on the crane superstructure. The solid-state inclinometer is housed in a separate enclosure on the vessel in order to give the true angle of heel.
Lloyd’s Register – Royal Institution of Naval Architects
Hook Marine are past winners of the industry prize in the LR-RINA Safer Ship Awards for the concept of the Kranskan™ safety indicator.
The judges in this international competition said that they “felt that the quality of this entry will be a benchmark for future awards”.