JD Neuhaus Hoists for Use in Challenging Underwater Environments

German manufacturer JD Neuhaus is marketing a range of products for use in underwater environments.

Divers are very often working alone, in conditions of variable depth water pressures and temperatures, combined with poor visibility while also battling with ocean currents. With all these problems to contend with, any tools they use need to be rugged, reliable, easy to operate and comply with the highest performance standards.
JDN hoists offer capacities from 250kg up to 100t, with specialised units of 200t lift capacity recently supplied for BOP (blowout preventer) handling. The development of subsea hoists means that underwater as well as on-deck lifting operations for a wide range of operational, maintenance and repair functions can be undertaken on jack-up rigs, semi-submersible platforms, drill ships and FPSO (floating production, storage and offloading) vessels.

The viability of JDN hoists in the underwater environment was demonstrated when its air operated hoists were used for the removal and replacement of a 50t rudder on a fully loaded bulk carrier vessel. After breakdown during a voyage from Brazil to China, the ship was first towed to a safe mooring off the coast of Venezuela, where the rudder removal and replacement work was undertaken. Three standard air operated JDN Profi 25t capacity hoists were used in conjunction, with units being subject to full rebuild procedures upon job completion.

The hoist lift chains provide a 3m raise/lower capacity as standard for variable load options of up to 3.2t or 6.4t respectively. Variations on the length of lift chains or hose feeds to the pendant controller can also be changed for greater versatility. Hoists designed for higher or lower load limits, together with products capable of operating at depths greater than 70m, could also be manufactured if required.