A wire rope hoist is a hoist that
utilizes wire rope as the lifting medium. It is often powered
electrically or pneumatically. This lifting device is made up of
a rope storage drum, motor(s), gear box and braking system, and
is suspended from a monorail or bridge beam(s) by means of a
trolley. It may also be stationary mounted. A crane is a machine
used for lifting and lowering a load, and moving it
horizontally. A crane's drives may be manual, powered or a
combination of both. Cranes are typically used when there is
insufficient (or intermittent) flow volume such that the use of
a conveyor cannot be justified. They provide more flexibility in
movement than conveyors, and less flexibility in movement than
industrial trucks. Loads handled by cranes are more varied with
respect to their shape and weight than those handled by a
conveyor. Most cranes utilize hoists for vertical movement,
although manipulators can be used if precise positioning of the
load is required.
Many different types of cranes are used
for material handling applications. These include overhead
cranes as well as cherry picker type boom lifts, mobile and
self-propelled cranes, straddle and counterbalanced
(cantilevered) cranes. Portable and mobile floor cranes can be
equipped with fixed or telescopic booms as well as mast rotation
when equipped with outriggers. Lifting can be performed with the
boom itself or a winch operated cable lift.
Selection
Criteria The size of the hoist is determined by the load
spectrum, average operating time, safe working load and rope
reeving.
1. What are the operating conditions ? 2.
What is the specified safe working load ? 3. To what height
must the load be lifted ? 4. What is the required lifting
speed ? 5. Do the loads need to be lifted and lowered with
great accuracy ? 6. Is horizontal load travel necessary ?
7. How the hoist to be controlled ?