Overview of Mobile crane

Mobile cranes are cable-controlled cranes mounted on crawler or rubber-tyred carriers, or hydraulically powered with telescopic booms mounted on truck-type carriers or as self-propelled models.They are designed to be easily transported to one location, and with different types of loads and cargo, requiring little setup or assembly..

Overview

Mobile cranes typically operate a boom with a hook suspended from the end of the boom by wire rope and pulleys.The wire rope is operated by any prime mover available to the designer, through various transmissions.Steam engines, electric motors and internal combustion engines (IC) have all been used.The transmission of older cranes is often a clutch.This was later modified when IC engines were used to match the "maximum torque at zero speed" characteristic of steam engines by adding hydrodynamic elements culminating in a controlled torque converter.The operational advantages of this arrangement can now be realized with electronic control of the hydrostatic drive, which is becoming standard due to size and other considerations.Some examples of this type of crane can be converted to a demolition crane by adding a demolition ball, or to a bulldozer by adding a clamshell bucket or dragline and bucket, although design details may limit their effectiveness.

History 

Prior to 1870, cranes were fixed in one position, except for some mounted on flat cars, railroad cranes, which provided some limited movement.The Appleby Brothers demonstrated steam-powered cranes in Paris in 1867 and Vienna in 1873.In 1922, Appleby Corp. manager Henry Coles began production of a truck-mounted crane called the Petrol Electric Lorry Crane.In 1939, Coles was acquired by Sunderland's Steel Limited. Hiab invented the world's first hydraulic truck-mounted crane in 1947.The name Hiab comes from the commonly used acronym for Hydrauliska Industri AB, a company founded in Hudiksvall, Sweden in 1944 by Eric Sundin, a snowboard manufacturer who discovered a way The method of powering the crane.Major events in the development of cranes include the adoption of the internal combustion engine in 1922 and the invention of the telescopic jib.Prior to 1960, cranes carried extra booms to increase height, which increased operating costs.In 1959, crane specialist R.H.Neal, hydraulic specialist F.Taylor and design director Bob Lester brought together all three modern cranes.The Coles Hydra Speedcrane launched in 1962 and was further modified in 1966 with a 10 tonne fully telescoping hydraulic boom, followed by a 30 tonne four wheel drive 'Husky' military version in 1968.In 1972, Steels was forced to merge with the Acrow Group, losing some of its most valuable employees, including Don Hassel and Johnny Johnson, who opened a new manufacturing facility.With the support of the British Crane Hire Corporation, they acquired a small factory unit and ordered every element of their production from subcontract suppliers.In 1976 the Cosmos team created a 25 tonne crane incorporating several new developments.