The hook is the main component of the lifting machinery, is the most common kind of spreader in the lifting machinery. The hook is often suspended from the wire rope of the lifting mechanism with the help of components such as the pulley set The hook set is made up of several simple parts such as hooks, nuts, thrust bearings, beams and pulleys. Hooks are divided into single hooks and double hooks according to the shape, single hooks as the name implies is a hook to lift goods hook, it can only lift lighter lifting goods, double hooks lifting lifting goods is relatively heavy. The hook classification is extremely wide and generally includes: shackles, rings, round rings, pear rings, long rings, combined rings, S hooks, nose hooks, American hooks, ram's horn hooks, eye-shaped hooks, with insurance card ring screws, chain shackles.It with unique, novel, high quality and safety features.
But when it comes to lifting goods by hook, it is impossible not to think of those who have fallen goods due to unexpected failures, thus causing major personal injuries or property safety. Therefore the quality requirements for the hook are quite strict, and to achieve the safety performance of the hook, it is necessary to start from the structural design, material configuration, manufacturing methods and other aspects of the hook, and in the manufacturing and use of the process to strengthen the inspection and maintenance, found any unreasonable situation, must be timely scrapped and renewed.
Materials for crane hooks
Questions about the material of the hook. Lifting hook in addition to bearing the weight of the item, from the crane itself in the lifting mechanism in the moment of starting and stopping the impact load energy, is not to be underestimated, because the hook in the process of operation often subject to impact, so the hook must have a high mechanical strength and good impact toughness, and general high-carbon steel material brittle, usually sensitive to stress concentration and crack defects, are used to better quality of low carbon ballast steel or low carbon alloy steel manufacturing and so on.
In addition, some hooks are cold-formed, hot-forged and welded, in order to eliminate cold stress, thermal stress and welding stress, but also must be appropriate heat treatment, such as tempering treatment.
Production process of crane hooks
Hooks are divided into single hooks and double hooks according to shape; forged hooks and laminated hooks according to manufacturing methods.
Among them, the forged hook is a whole manufacturing, manufacturing simple, easy to use, so the application is more widespread, single hook is mostly used in the lifting capacity of 80 tons or less work occasions. However, the force is not good, once the forged hook is damaged, it can also be said to be all scrapped.
When the lifting capacity is large, a double hook with symmetrical forces is often used. Stacked hooks are made of several pieces of cut and formed steel plates riveted together, with a cushioning pressure plate in the middle, which can cushion the energy brought about by the pressure, so that the whole hook will not be damaged when cracks appear in individual plates.