What is a Trolley? The trolley is the mechanism that moves the hoist along the bridge girder of a crane. The hoist is moved horizontally along the top or underside of the bridge girder to position it above a load (Figure 1, Motion 2).
What is a hoist trolley?
A trolley (pictured below) is a wheeled mechanism from which a hoist is suspended to provide horizontal motion of the hoist along a beam/bridge rail.
What is the hook on a crane called?
A lifting hook is a device for grabbing and lifting loads by means of a device such as a hoist or crane. A lifting hook is usually equipped with a safety latch to prevent the disengagement of the lifting wire rope sling, chain or rope to which the load is attached.
What are the components of a crane?
The Various Functions of Mobile Crane Parts
- The Driving Components. In any mobile crane, one of the common components will be the driving system used to make it mobile. …
- The Operator’s Cabin. The operator’s cabin houses all of the crane’s controls. …
- The Boom. …
- Hoist and Hook. …
- Hydraulic Pump. …
- Outriggers and Counterweights.
6 февр. 2020 г.
What is the end of a crane called?
JIB CRANE – A crane design whereby the bridge girder (commonly called the boom) is fixed at one end, allowing the opposite end to cantilever. The fixed end generally is hinged to allow rotation. LIFT – Maximum safe vertical distance through which the hook, magnet, or bucket can move.
What is the difference between a hoist and a lift?
What is the difference between a hoist and a lift in construction? … In simple terms, a hoist is a construction device that typically uses a pulley system to raise objects upward while a construction lift typically includes an aerial platform maintained by a specific form of extension and fitted on a vehicle.
What are some examples of different types of hoists?
There are three types of residential hoisting devices:
- Wheeled hoists.
- Stationary hoists.
- Ceiling lifts.
What part of the crane is used to lift and lower the load?
Hoist – A mechanical unit that is used for lifting and lowering a load via a hook or lifting attachment.
Why does the crane need to rotate?
Why does the crane need to rotate? … It has an input force or effort from the diagonal cables right at the top of the crane pulling the jib up, and a load pulling the jib down.
Who can operate a crane?
Operators of most cranes above 2,000 lb. capacity when used in construction will need to be either certified by an accredited crane operator testing organization, such as the National Commission for the Certification of Crane Operators (NCCCO), or qualified through an audited employer program [§ 1926.1427(a)].
What are the three functions of a crane?
The main purpose of a crane is to lift extremely heavy amounts of weight. A typical crane is equipped with a hoist rope, wire ropes or chains and sheaves.
Modern day cranes are used for:
- Construction Materials.
- Railroad Tracks.
- Shipping Materials/Equipment.
- Scrap Metal.
- Mobile Homes.
5 нояб. 2015 г.
What does OSHA consider a crane?
A crane is a machine for lifting and lowering a load and moving it horizontally, with the hoisting mechanism an integral part of the machine. … Floor-operated crane means a crane which is pendant or nonconductive rope controlled by an operator on the floor or an independent platform.
What is the boom of a crane?
The Boom: The boom is probably the crane’s most outstanding and identifiable feature – this is the long, telescopic or fixed arm that is used to move objects. The Counterweights: The crane’s counterweights are near the cab’s exterior – they prevent the crane from becoming unbalanced when lifting heavy loads.
What stops the crane from falling over when it lifts something?
Why Don’t Tower Cranes Fall Over? This is mostly down to the concrete base, which is massive and needs to be poured weeks before the crane arrives. The triangulated cross-member structure of the mast gives it more stability and prevents bending. Plus, it’s anchored and bolted to the ground.
What is creep speed?
CREEP SPEED: A very slow, constant, continuous, fixed rate of motion of the hoist, trolley, or bridge: usually established at 1% to 10% of the normal full load speed.
How much does a crane cost?
Mobile Crane ($125,000 – $525,000+) – A common type of crane that is transportable, but may have limited range compared to the telescopic crane.