There are different types of cranes which are widely used in the construction and Civil engineering industry, in the lifting up of heavy weight material or equipment, and in case of manufacturing industry for lifting purpose and movement of heavy loads from one place to another. All safety precautions always must be observed whenever lifting up or down and moving any heavy loads to ensure the crane mechanical and equipmental C.G stability.
Definition of Crane
The crane is generally fitted with a cylindrical type drum that can easily windup the metalic rope on it and chains or wire of ropes for holding up the heavy materials. The sheaves are also installed, which are basically used for the lifting up and lowering down of the heavy objects, and also for the horizontal movement at any direction. The Cranes actually create mechanical advantage by a suitable configuration automation mechanism. Then, the loads can be moved at any location and lifted up or down that otherwise it would not be within human capacity.
Stability of the Crane
Balancing stability of any crane is of main significance to ensure the life safety of humans and good materials. Although sufficient safety features and options are incorporated in crane mechanism by the manufacturer company, but the user always must be aware of the safety requirements and fatality risk that must be totally fulfilled to ensure worker life safety.
- The good stability of cranes can be scientifically achieved by ensuring that the total of balancing moments at the base of crane should be zero or null. In actual usage purpose, the toal permissible load to be lifted up , which is called the rated load of crane, is always less than the tipping crane load. This actually provides a margin of safety for the crane movement stability.
- Basically, As per recommendation of the crane safety standard the rated loads will be 75% to 85% of the tipping loads of crane. This safety features of crane are easily determined by keeping in view that the design features of the crane, the soil conditions and properties, the uniformity of ground level condition, and other relevant factors.
- Cranes are widely used on ships ant port have more strict safety margins due to the dynamic load movement situations. Whenever the cranes are used on a fixed base platform, the structural moment produced by the jib, boom portion, and load is opposed by the platform fixed base. The stress which is induced in the base must be lower than compared to the material yield stress value.