The overhead traveling crane hook block is the most commonly used acquisition device and consists mainly of a hook, a movable pulley, a pulley shaft and a bearing. Working with fixed pulleys and hook blocks, fixed on the structure, it is the composition of the pulley block.
There are many classifications of crane hook blocks, mainly including:
The details are as follows:
Ring: It has the same weight and light weight, but it is quick and convenient to use. It is mainly used in the tedious work of weighing from a large crane.
Plate type: single hook and double hook. Generally, a plurality of C3 and 16Mn steel plates are repeatedly riveted. The hook has a simple structure, reliable work and convenient maintenance. The single hook is mostly used on casting cranes, and the double hooks are used on general cranes of more than 100 tons. Their structural dimensions have been in series, and it could be directly selected without calculation.
Forging: Single hook eccentric force is not as good as double hook symmetrical force, so small and medium tonnage cranes with a capacity of less than 75 tons usually use single hooks, and large tonnage cranes with more than 75 tons usually use double hooks. This type of hook is widely used and has become a system. In general, it is not necessary to calculate, you can directly select according to the table. Safety hooks should be provided when there is a risk of decoupling the wire rope. Select single hook or double hook depending on the actual working environment.