Engineering:Travel lift
A travel lift (also called a [boat hoist] or boat gantry crane, or boat crane) specialised type of crane used for lifting boats out of the water and transporting them around docks or marinas.[1] These cranes allow boats with masts or tall super structures to be transported around hard stands as the tall mast can pass into the centre of the crane. The travel lifts typically have two rectangular sides joined by a single spanning beam at the top of one end. The crane is mobile with four groups of steerable wheels, one on each corner. Boats are typically lifted using straps, slung between the two sides which can be passed under boats when either in the water or on the hard stand. Steel wires on pulleys are used to lift the boat.
To remove a boat from the water, the boat is positioned in a narrow dock, or lifting well with two paths along each side, which are at the same level as the hard stand. The travel lift can then be driven onto the paths so that it is positioned over the boat. The boat can then be lifted above the level of the hard stand and driven around to the place where it is to be lowered.
Travel lifts - Boat Hoist can have a variety of lifting capacities from tens of tonnes used for small boats to well over 1000 tonnes which can be used for sizeable ships. They typically lift loads at around 1 m per minute and can be driven at speeds of up to 40m per minute.[2]
Boats need to be removed from the water for a variety of reasons including anti-fouling and removal of marine growth, maintenance and inspection and long term storage. Because of their slow speeds, marine travel lifts are impractical for regular transport of boats.
There is also an Amphibious version that can be lift the boat directly from the sea.[3]
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