Selection and maintenance of crane pulley block

Nowadays, the economy is developing faster and faster, which directly promotes the development of the construction industry.

Crane as one of the main equipment in engineering construction, the working strength is becoming more and more big, under the condition of the high strength work cycle for a long time, will cause certain damage to the crane itself and parts, this needs us to consider how to reduce the crane work dynamics, and the pulley is crane components shall be must consider one of the most important parts.

The main purpose of the pulley is to wear wire rope, change the movement direction of wire rope and achieve the purpose of saving power.

According to its effect, it can be divided into fixed pulley, movable pulley, pulley block, guide pulley, etc.

In the hoisting operation, if only the fixed pulley is used, the direction of the force can only be changed, which can not play a saving role.

The use of movable pulley can be a labor-saving function, but it cannot change the direction of the force.

In this way, the fixed pulley and the movable pulley must be connected together to form the pulley block to meet the crane operation requirements.

The pulley is divided into hot rolling pulleys, cast iron pulley, cast steel pulley, nylon pulley and aluminum alloy pulley.

Small weight and low working level can be used for cast iron pulley, nylon pulley and aluminum alloy pulley.

The high weight and high work grade choose cast steel pulley and hot rolled pulley.

The explosion-proof crane USES nylon pulley or aluminum alloy pulley.

The selection of pulley material can be considered in terms of weight, working level and explosion-proof requirements.

Binding in order to reduce the effect on the steel wire rope, rope groove on the new pulley diameter is slightly larger than the diameter of a new steel wire rope, the crane pulley on whether it is made of what materials are being worn.

The different forms of pulley wear are related to the use condition. The more frequent the use, the more serious the wear.

Because the condition of the pulley has a great influence on the whole life of the wire rope, the pulley should be inspected regularly, and the key of the inspection is the wear of the pulley groove.

Roller wear is caused by cut wire rope pulley, when the pulley rope groove too narrow, the pulley can reduce the service life of wire rope, and reduce the use of the newly installed wire rope performance, the new steel wire rope will come under strong pressure from the radial.

For high-performance rotation resistance wire rope breakage of the pulley is particularly destructive, pressure will cause breaking in a very short period of time or change in the structure of strand, cable, such as silk, ran out of the waves or deformation.

The damage of the high performance resistance rotating wire rope can be determined by the length of the core and the outer string. According to the requirements of ISO4309, the typical damage is up to the standard of scrap.

Crane owners can prevent this damage by replacing the new pulley or the grooves, and all the used pulleys should be tested before installing the new wire rope.

As long as the surface of the rope groove is smooth and the groove width is larger than the actual diameter of the wire rope, no modification is required.