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Various lifting and handling facilities invented in the course of thousands of years can be grouped as follows:
Port lifting equipment is described in Port Facilities and Equipment section containing information on such lifting equipment as windlasses, crabs, pulley block hoists, cargo booms, shipboard cranes, lift devices, transporters, winches, and on auxiliary handling equipment for special-purpose vessels.
The block is the simplest lifting device consisting of a disk (wheel) with a guiding groove. It is used for hoisting relatively small light cargoes and like another simple mechanism – the winch – can be used separately or as a member of complicated mechanisms.
Most often, electric winches are used onboard. Ship winces can be load, field-load and hatch-closing winches as well as a separate group of towing winches.
The pulley block hoists is a suspended lifting device.
The anchor windlass is a winch mechanism for dropping and weighing anchor as well as for mooring hauling in.
The cargo boom is a beam-jib which low end is fixed at the mast with a hinge while its high end hangs on the cable wire so at the boom could change canting angle and rotate about vertical axis. The cargo is lifted and lowered with a winch. The frames are used, too. Their construction is similar to that of cargo booms with A-frames instead of beams.
The ship cargo crane is the most heavy-duty and convenient hoisting device of all onboard lifting equipment. Generally, revolving cranes are used onboard which differ in boom arrangement (telescoping, rigid and L-shaped). Ship lifting equipment of container carriers comprises a frame crane. By type of a driver, cranes can be mechanical, hydraulic, electrical.
Today, customized lifting equipment is in requisition. Most frequently, non-standard requirements are specified to cranes. So, Tekhnoros, the Russian plant for manufacture of handling facilities, manufactures them only against special customer terms of reference.
Other equipment (winches, for example) is represented with a great number of models and it is very easy to find a necessary device in the standard product mix.
Central Research Institute of marine engineering developed an all-purpose ship crane which can deliver the cargo from one ship to another in motion and with rough water up to 4. To control rocking, a special device is used. Box section boom reach can be 60 m.
In some countries, steel of cable sheave is replaced with plastics, however in the cold, plastics loses its flexibility, strength, becomes fragile and breaks.
In various countries crane metal works are made of steel with various low temperature limits. Thus, temperature limit of crane details of some French and Italian companies is -20°C which is not optimal for Russia. In the northern seas, the temperature can be lower despite the global warming. As to manufacturing quality, the most common defect is low-grade welded seams. So, when ordering imported equipment, it is necessary to turn attention to the test report availability, since many companies do not carry out tests referring to the available weld procedure certificate.
As to load grippers, one of the trends is cross-beams with several points of rope fixing. In such case, dog leg possibility decreases, so accident risk is lower too. Cross-beams are used for handling of high-capacity or irregular-shaped cargoes.
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