YG 135 Hook Blocks are made of free block and hook, based on the practice of usage, the block is similar to current domestic product, the hook has a reasonable and integrity structure if compare to current domestic product.
Free block is made of a set of free wheels inside the horse-head to do reciprocating movement. It is formed by four rollers and connected with crown block by steel wire. The body of the hook is formed by the main hock and the lifting eye. The main hook is used to hang the swivel. The lifting eye is used to hang the lifting ring.
In case to decrease the concussion caused in hoisting and un-installation, the hook has machine buffering device, also has hydraulic pressure buffering device.
This device is mainly formed by hydraulic pressure spring set and piston. Inside the hydraulic pressure spring set, there are full of hydraulic oil. When the hook is loading, the charge is added to the hydraulic pressure spring set by friction ball, and make it down. At the same time, the capacity at the lower part of the hydraulic pressure spring set will increase, create a instant low pressure zone. Because of this, the fat liquor will flow toward the bottom of piston by through the gap at the exit line of piston and the inside holes of piston. This kind of flow has a very large resistance, the direction of the resistance and the movement of the hook are heading opposite direction. This creates damping to make the hook down, when uninstall the hook, the spring gets loosed, push the hydraulic pressure spring set upward.
At this time, the fat liquor at the lower part of the hydraulic pressure spring set gets pressed, will flow to the upper cavity only through the gap at the outside of piston. The resistance of liquor stream is directing downward, creates damp at the time un-installation. After the hock has this kind of buffering device, the bump has decreased at loading and downloading, and makes the operation even more stable.