Choosing an Electric Hoist
The conditions in which an electronic hoist must work should be considered when making a selection. It is essential that careful consideration be given to the frequency of use, load weight, length of lift, distance of horizontal travel, efficiency, safety and economy. There are literally hundreds of options available in electric hoisting equipment to answer the industries need for a powered lifting tool that speeds hoisting, conserves human effort, provides maximum safety and cuts handling cost.
Three Factors to Consider When Contemplating an Electric Hoist for your Application:
Capacity: The load to be lifted is the primary consideration, and the maximum load weight governs the minimum capacity of the hoist. This capacity must include the largest weights that you anticipate lifting, plus the weight of any grab, spreader bar, or other lifting device which attaches to the hook.
Headroom: It is generally desired in normal plant applications to have as high a hook height as possible for off-loading trucks, turning over large fabrications, etc.; however, this consideration should be weighed closely against the cost of the crane and in the required height of a building to accommodate excessive lift.
Many options are available to achieve maximum hook height. Some of these options can be rather expensive and must be evaluated against construction costs of the building in which the crane will operate. Even though close headroom options for the crane are costly, it is often less expensive than adding additional building height to accommodate standard lift equipment.
Headroom is defined as the distance between the beam, or track, and the bottom of the hook. Headroom distance varies between manufacturers and styles of hoists. If headroom is critical, check with CraneTec for exact dimensions.
Speeds: Electric hoists can be furnished for single speed, one-step automatic acceleration, two- speed, or variable speed operations. Most applications can be handled with single speeds due to the wide range of single speeds available. One step acceleration permits a gradual increase from zero to full speed. Two speed options allow a selection of low speed for spotting loads and higher speeds for fast lifting. Variable speed allows lift at any speed between zero and full speed.
“Creep” speeds on hoists are very slow, accurately positioning, second speeds. The speed is usually one-tenth to one-fifteenth the main hoist speed, yet this extreme slow speed is very essential in accurate placement of delicate loads. This type of speed arrangement is normally accomplished by separate motor drive attached to the main hoist motor. Two speed hoists are more common and the low speed will be one-fourth of the main hoisting speed.