1. Manual Hoists - Manual hoists are designed for occasional, non-production lifting where fast lifting is not required. Manual hoists feature two different chains; one to lift and lower the load (control or hand chain) and one to support the load (load chain). Manual hoists are operated by manually raising or lowering the control chain using a "hand over hand" motion to lift or lower the load. The pulling action of the hand chain turns a series of gears and sprockets located inside the hoist, which results in the raising or lowering of the load chain and hence the load itself. Manual hoists (chain falls) are available in ½-ton to 25-ton capacities and are ideal for use in rigging, maintenance, construction, shipbuilding, and automotive applications.
2. Electric Hoists - Electric hoists utilize an electric motor to turn the hoist’s internal gearing which in turn raises or lowers the load connected to the load chain. The clockwise or counterclockwise rotation of the drum is controlled by the operator's use of a pendant control featuring up and down buttons as well as an optional emergency safety stop. The electric motors found in hoists more often than not utilize either 220v/ 440v or 230v / 460v voltage and typically require a hard wire type connection. However, some of the lighter duty shop hoists operate on 110v and can actually be plugged right into a household style electrical wall outlet. Electric hoists are fairly economical, but are limited in their use by what is known as their duty cycle. Every electric motor requires a certain amount of rest after a period of use. Disregarding the duty cycle ratings of an electric motor will result in premature motor failure and costly repairs. Electric hoists are not designed for 100% duty cycle operation and are not recommended for continuous production use. They are available in 1/8-ton all the way up to 100-ton capacities.
3. Pneumatic (Air) Hoists - Pneumatic hoists are typically used in industrial production environments. These units feature either a rotary vane or piston driven air motor powered by compressed air. The greatest benefit of air hoists is that they have a 100% duty cycle rating, meaning unlike their electric counterparts, they never need to rest. Pneumatic hoists are however, only as good as the quality, pressure, and flow rate of the air that feeds them. One disadvantage of air hoists is that they consume a moderate to large amount of compressed air, which in turn calls for an air compressor capable of producing enough air flow to meet the cubic feet per minute (CFM) requirements of the hoist. Hoists operated below the rated CFM will not perform to their rated performance. Additionally, clean, dry, and lubricated air is critical to extending the operating life of an air hoist.
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