How to maintain manual chain hoists?

Manual chain hoist, also known as inverted chain or hanging chain, is a lifting machine used in conjunction with three wooden frames or herringbone frames. His lifting capacity is between 0.5-20 tons, and according to the lifting capacity, it can be 0.5, 1.0, 1.5, 2.0, 3.0, 5.0, 10 and 20 tons. The lifting height is determined by the chain length and the height of the herringbone, generally within 5 meters. In addition, the manual hoist can also be used to tighten the wind rope of the mast and the rope of the binding member during the transportation of the member.

The structure of the hand chain hoist includes gear transmission and worm transmission, etc. The gear transmission is the most commonly used and has higher efficiency. Its specifications include SH type and WA type. Figure 2-10 is a chain chain hoist with a planetary gear reduction mechanism, which can lift and move heavy objects within a short distance, as well as tighten the components to control the direction. It can be used in vertical, horizontal and oblique directions. When lifting, hang the hook at a fixed height, first hand the chain back in hand, loosen the lifting chain, so that the number has the largest lifting distance, and then slowly tighten it to lift the heavy object. Figure 2-11 is a worm type manual chain hoist. When lifting, the chain is tightened by hand, and the worm is driven by the sprocket to rotate, and the worm drives the worm to roll up the chain and make the movable block rise.