Overhead Crane Basics

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An overhead crane is a type of equipment or a machine that is used to lift or move heavier objects from one place to another with great precision. Overhead cranes are designed according to their needs and applications. These cranes are manufactured in all types of configurations. However, the parts can be engineered or swapped out to increase the efficiency, capacity, and performance of the cranes.

Choosing the Right Overhead Crane

Overhead cranes are of many shapes and sizes to streamline the production process. But there are some factors to consider before choosing the right type of crane. These are:

• The motion of the overhead crane.
• Type and weight of the load.
• Location of the crane, either indoor or outdoor.
• Usage of the crane.
• Capacity required.
• The span of the crane.

Components of Overhead Cranes

The components of overhead cranes are:

●     Crane Hoist

The hoist raises, lowers, holds, and lifts the load. It is done by using a chain or rope. The hoist can be operated manually, by using electricity or also with air pressure.

●     Hook of Crane

           The load is supported by the hook. The hook is attached to the hoist.

●     Trolley Component

           The trolley is the component that holds the hoist and moves horizontally to fix the position of the hoist and hook before picking up the load. Trolleys are categorized as under running and top running.

●     Crane Bridge

A bridge is the structural and fundamental component that helps to connect the runways and also helps in moving the hoist forward and backward using a trolley. A bridge is actually a load-bearing beam and it runs along the width of the building. It consists of one or two beams referred to as single girder and double girder. These girders are made up of rolled steel. Sometimes, fabrication can be done by welding the beams into steel box designs.

●     Crane Runway

It is the main part of the building structure as beams. The crane moves on the runways.

●     Runway Rails

Rails are there on runways on which the crane moves. It is used to move the bridge back and forth.

●     End Trucks

End trucks are used to move the bridge up and down by utilizing the wheels present. End trucks are located on either side of the bridge. The wheel configuration is 2,4,8 depending on the movement of the crane.

●     Bumpers

Bumpers are designed to absorb the crane energy and reduce its impact. It is done by controlled rest and minimized forces when the crane reaches its endpoint.

●     Controls

Controls are usually present on the panel of the crane and from there, all the movements of the crane are controlled.

Types of Overhead Crane

Five different types of overhead cranes are there. All of these have different capacities and functions.

●     Bridge Cranes

• It has two overhead runways built into the building support system.
• It has two types of configuration, single girder, and double girder.
• Bridge cranes help in up and down movement on the runway.
• Bridge cranes are also divided into two types depending upon their capacity and environment.
• Process cranes are heavy-duty for specific needs (class D, E, and F).
• These are top running, double girder configurations and customized to perform specific and high capacity lifts.
• Process cranes are used in automotive assembly plants, steel mills, container yards, and lumber mills.
• Modular cranes are economical and are used for class C and with some engineering can also be used for class D.
• These cranes are usually found in smaller manufacturing facilities, smaller-sized mills, and machine shops.

●     Monorail Cranes

• It uses a trolley to carry hoists along a single path.
• It is commonly found in production or assembly lines.
• The materials are usually run back and forth in a straight line.
• The switches, branches, and elevation changes can make a curved path.
• These cranes are designed for lifts.              

●     Jib Cranes

• Jib cranes are of many types and styles and do not use runways.
• These are stand-alone or wall-mounted and have a variety of capacity, spans, and heights.
• Jib cranes are space-saving and very economical.
• It offers a rotation of 180-360° and works best in small spaces.

●     Workstation Cranes

• Workstation cranes are specially designed for ergonomic means of moving and lifting loads.
• These cranes are lighter-duty and work well in smaller spaces.
• These cranes can be free-standing or ceiling-hung.
• These can be under-running or over-running.
• Workstation cranes are versatile and can be customized according to needs.

●     Gantry Cranes

• It is similar to bridge cranes, but it uses legs to support trolleys and hoists.
• The crane legs move on the fixed rails that are either embedded in or laid on the top floor.
• Gantry cranes work well where there is no need for overhead runways.
• These cranes work well outdoors like in shipyards, railyards, etc.

Uses of Overhead Cranes

• These are helpful for loading and unloading materials from trucks.
• For the movement of materials more efficiently in a facility.
• It helps in flipping and pulling dyes from the stamping machines.
• It is also used in manufacturing facilities for feeding raw materials into machines.
• For controlled movement of materials.
• Overhead cranes are also used for moving containers on shipyards or railyards.

Advantages of Overhead Crane

• Overhead cranes increase work efficiency 2-3 times compared to manpower.
• Overhead cranes offer a lot of safety in warehouses or manufacturing facilities.
• Loading and lifting dangerous chemicals or machinery becomes easier with these cranes.
• Overhead cranes minimize on-site accidents if used properly by a skilled worker.
• It has also reduced products or materials damage.
• These cranes streamline the production process.
• These cranes are lower in cost also.
• It is also a green solution to reduce environmental impacts.

Using overhead cranes should be done by skilled workers and professionals to avoid on-site accidents. For this purpose, Cranes101 offers an overhead crane safety training course, both live and online, depending on what works best for you.