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Construction hoists are used to lift people or materials to various heights alongside a building or structure being built. Some types of construction hoists are built exclusively to haul materials, while others are built to haul both materials and people. Jib boom cranes, for example, can only move materials, while elevator hoists can be used to lift workers to high levels of a scaffolding structure. Another type of hoist uses a pulley wheel with a cable wrapped around it numerous times; a hook at the end of the cable is attached to materials to be lifted, and a motor rotates the pulley to move the cable.
A jib boom crane features a vertical post mounted at the top of a building or structure; a horizontal jib is mounted to this vertical post, and a pulley is mounted to the end of the jib. A cable is secured to the crane structure, and it runs through the pulley at the end of the jib. The cable may be wrapped around another pulley closer to the vertical post, and this pulley may be motorized to control the feed of the cable. At the end of the cable is fixed a hook or other securing mechanism, which can be attached to the items to be lifted. These construction hoists are used only to haul materials, and the materials must be bundled or otherwise secured to accept the hook. This type of hoist is particularly useful for hauling materials and moving them to a different location by moving the jib.
An electrical hoist can be used as well to lift objects in a similar manner as the jib joist, but this type does not use any type of vertical post or jib. It is essentially a motorized pulley with a cable wrapped around it numerous times; the body can be bolted or otherwise mounted to a fixed structure for stability, and the cable can be raised or lowered according to the operator's needs.
Some types of construction hoists are both large and stable enough that people can be moved in them. These units are motorized, and they travel along a track mounted in sections to a building or structure, or to an independent support system. The car of these construction hoists will use a rack and pinion system to move up or down, and brakes are usually mounted on the car to allow the operator to stop it in an emergency. The car itself is usually made of a high grade metal such as certain types of steel, and it will feature gates, rails, or other containment systems to prevent users from falling out or to prevent materials from shifting or falling during lifting.
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