Views:85 Author:Site Editor Publish Time: 2019-08-27 Origin:Site
Lifting chain is an essential and important lifting device for cranes. The length of the chain can be adjusted according to the lifting height of the lifting weight, which plays an important role in improving the operating efficiency of cranes and expanding the operating range of cranes.
Lifting chains can be divided into four types according to different uses: Transmission chain is mainly used to transfer power; Transport chain is mainly used to transport materials; The towing chain is mainly used for towing and lifting; Special special chain is mainly used for special mechanical device, with special function and structure.
Crane chain in use should pay attention to its maintenance. The sprocket wheel should be installed on the shaft without skew and swing. In the same driving component, the end faces of two sprockets should be located in the same plane. When the center distance of sprockets is less than 0.5 meters, the allowable deviation is 1 mm; Sprocket center distance in 0.5 meters above, the allowable deviation of 2 mm. But it is not allowed to have friction sprocket tooth side phenomenon, if the two wheel braided too large easy to produce detaching and accelerated wear. The offset must be checked and adjusted when the sprocket wheel is replaced. The tightness of lifting chain should be appropriate. if too tight, it will increase the power consumption and bearing will be easy to wear; When it is too loose, the chain is easy to jump and detach. Lift or press down from the middle of the chain, the center distance of the two sprockets should be about 2%-3%.
The following items should be paid attention to when lifting chain hook is used. When the Angle of lifting lug is large, shackle pin should be inserted from outside to inside. Hook up personnel should hook up in order of operation. When the position of lifting lug is not in good condition, more than 2 persons shall hook. The hook personnel shall check the shackles, lifting lugs and welding status after the hook is completed, and shall use "lifting lugs OK" to carry out inter-index difference.
The first step of hook operation is to judge the lifting weight according to the drawing. Then decide the hook method and select the spreader. Try not to use a wire rope to lift things. When the wire rope contacts the Angle of the object, it should be protected by soft cushion. When the wire rope has to be wound around the pipe or other object for hoisting, the wire rope must be wound around the object once and connected with shackles, and it is a two-point hoisting.
In the end, we will list the comparison of lifting chain and lifting chain hook. Compared to the lifting chain hook, lifting chain is more flexible, can use smaller diameter sprocket and reel. And transmission ratio is small. The size of the transmission mechanism is also small. In addition, it is resistant to corrosion. The disadvantage of lifting chain is not safe and reliable, and it can not resist impact. Besides it can't be used for high speed. The chain often produces slippage and friction in the movement, so it is easy to wear.