HYDRAULIC CRANE WITH CONSTRUCTION, WORKING AND NEAT IMAGE

MECHANICAL TIPS AND STUDY MATERIAL

This device has wide application in warehouses, dock slide, work shops etc. It is used for transferring or lifting bulk loads.
The main components are 

1) Mast
2) Jib
3) Tie
4) Cylinder - Ram arrangement
5) Guide pulley
6) Jigger

Construction and working

www.studymechanical.com

Mast is the vertical structure from which jib and tie are attached. The mast can revolve around the vertical axis. The jib can be lowered or raised as per the requirement of crane.

The jigger which consists of sliding ram fitted in cylinder arrangement provides the necessary action for lifting/lowering the load. The lower end of cylinder- ram arrangement is provided with inlet for high pressure water.This end has fixed pulley block which in turn is fixed with cylinder jigger. The upper end of ram is connected to movable pulley which can move up and down.

The wire rope is provided through which load is attached which is to be lowered or lifted. This wire rope passes over the guide pulley And is fixed to movable pulley which in turn is attached to sliding ram.

Lifting of load

When the load is to be lifted, the high pressure water is admitted to cylinder of jigger which forces the ram to move upwards. As the ram moves upward the movable pully attached with it also moves upward. This increases tension in wire and distance between two pully blocks also increases. This action lifts the load. Similarly for lowering the load, water is allowed out of the cylinder, thus the ram comes down with movable pully and load is lowered.