A crane is a mechanical equipment made up of wire ropes, hoist, chains and sheaves. This machine is generally used for lifting purpose. It is even used to lower materials and move them horizontally. 

Cranes are employed in the transport industry mainly for loading and unloading of freight. Cranes were first invented by the Greeks. With the introduction of cast iron and steel after the industrial revolution, the designs of cranes got modified. Type of cranes: Cranes come in variety of forms depending upon their application: Jib cranes are generally used for construction purpose. The sizes range from smallest jib cranes to tallest tower cranes. These cranes are generally used for construction purpose. 

There are even floating cranes used to build oil rings. There is a simplest type of crane called EOT cranes (Electric Overhead Travelling cranes) used for handling and moving a maximum specified weight within a specified area. It can be operated either manually or with electrical power. Its capacity can vary upto 50 tons. Gantry cranes and overhead cranes, on the other hand, lift objects by a hoist. It can move horizontally on a rail or a pair of rails fitted under a beam. The gantry cranes can even run on rubber tyres in order to avoid the tracks. Small gantry cranes can be used in the workshop for lifting engines from vehicles etc. Gantry cranes are particularly used for lifting heavy objects. Huge gantry cranes may be used in the ship building industries. Amongst their attachments, C-hook and lifting beams are common. These are mainly used by the steel industries. 

C-hooks have a capacity of 5ton to 40ton. The lifting beams on the other hand are used for lifting hot metal ladles. They are used for load handling with two cranes in tandem. Capacity can range between 250MT to 450MT. Besides there are tongs and grabbers used for lifting tools. These have been modified and various forms have been adapted for specific usage. Two types of tong: Vertical coil tong- used for lifting coil, Motorised horizontal coil tong- used for handling coils. 

The crane should be placed in areas where there is absence of any further construction. The ropes used for erection should be tested for stability and the winches used should be used with retched stops. Besides, while erecting a crane, the angle of inclination of slings should not be less than 45O, sufficient clamps should be used for fastening the rope. While thinking of buying a crane, one must accompany a person with high degree of understanding and analytical ability of accurate engineering. In case you already have a crane it is always wise that you try to upgrade existing one instead of buying a new for capacity upgradation can save a huge amount of money instead of replacing the existing one. While thinking of buying a crane, one must accompany a person with high degree of understanding and analytical ability of accurate engineering. In case you already have a crane it is always wise that you try to upgrade existing one instead of buying a new for capacity upgradation can save a huge amount of money instead of replacing the existing one. 

While operating cranes, it should be kept in mind to inspect the lifter from time to time. Malfunctioned or damaged filters should not be used. Load balance should be checked, shocks due to sudden start or stop should be avoided, the load should be within its carriage limits, and the lifter should be inspected before each use.