Classification of Crane Hooks

The classification of crane hooks is very wide, generally including shackles, rings, piece hooks, forged hooks, rings, pear-shaped rings, combination rings, S-shape hooks, nose hooks, American hooks, horn hooks, eye-shaped sliding hook, ring screw with insurance card, chain shackle, etc. Now we will mainly introduce the following three types:

1. Chip hook

There are two types of piece hooks: single hook and double hook, which are generally riveted with multiple overlapping pieces of C3 and 16Mn steel plates. The hook has the advantages of simple structure, reliable operation and convenient maintenance. Single hooks are mostly used on foundry cranes, and double hooks are mostly used on general-purpose cranes over 100 tons.

2. Forged hook

Forged hooks are divided into two types: single hook and double hook. It is generally forged with 20, 20MnSi steel as a whole. Because the single hook is eccentric, the force is not as favorable as the symmetrical force of the double hook, so the small and medium tonnage cranes below 75 tons use a single hook, and the large tonnage cranes above 75 tons use a double hook.

This kind of hook is widely used and has formed a series. When the wire rope is in danger of decoupling, a safety hook is installed.

3. Flying Rings

The force of the ring is worse than that of the hook. When the lifting capacity is the same, its weight is lighter, but it is not as convenient to use as the hook, so the use of the ring is far less common than that of the hook. It is mainly used on cranes with frequent work and heavy lifting capacity. Its structure is divided into integral type and hinged type, the latter is used more.

Selection of crane hooks

In terms of manufacturing process, most of the hooks are currently required to be processed by forging technology. Since the strength and reliability of the hooks obtained by casting are not very good, they are basically no longer used. At present, many double-girder cranes have adopted the rotary hook group, which is more beneficial in realizing safe and automatic operation.

In addition, in order to make the hook of the double-girder crane more convenient, the selected hook should be able to rotate flexibly around the vertical axis. In other words, thrust rolling bearings should be installed between the nut at the end of the hook and the beam. In general, the hook of the double-girder crane can be selected according to our use needs. For specific details, it is best to consult the crane manufacturer to avoid the selected hook from being unable to use normally.

The Correct Use and Inspection Method of the Hook Group

In the process of using the hook set, professional operators are required to operate it. From installation to use, it needs to be carried out in accordance with the specifications. So how should the fully enclosed hook set be used correctly? The following content will be introduced in detail:

• Before using the hook set, it must be ensured that it is produced by a regular manufacturer and has a certificate of qualification. It cannot be put into use blindly, and its opening degree, weighing and other indicators should be carefully and more strictly inspected;
• Check the rated lifting capacity marked on the hook, which must not be less than the actual lifting capacity. If there is no mark or the marking of the lifting capacity is unclear, the rated lifting capacity shall be determined by recalculation and conformity test;
• The special hooks on the hoisting machinery have higher requirements on them, and the surface must be smooth without defects such as peeling, nicks, sharp angles, seams and cracks;
• Use kerosene to clean the three dangerous sections of the hook, and use a magnifying glass to see if there are any cracks. For plate hooks, check the wear of the bushing and pins;
• Pay attention to observation and inspection during the use of the hook set, check whether there are hidden dangers such as deformation, cracks, and cross-sections. It is best not to overweight, so as not to shorten the service life of the fully enclosed hook set.