When the chain hook of the group hoist electric hoist chain is broken (the use of long chains in the group hanging hoist is relatively rare, the group hanging hoist and hanging group hoist are upside down because of the compression spring to tension the chain long chain, so there are more cases) One chain of upside down group hoist is to be tensioned. If the chain is not tensioned, the chain is likely to hoard and cause a chain. When the chain weld is opened, the weld will not open when the chain is used normally, but if the chain length continues to be pulled diagonally and the chain is laterally stressed, the chain deformation causes the chain weld to break. (The force of a single chain of 7.5T electric hoist is 2.5T, the chain can be pulled 8T without quenching, the chain is not welded, and the quenching tension is above 2.5T) The main chain at the cruise ship: remove the nuts on both sides of the cruise ship and hook After the shaft is taken out, the chain can be moved later. After the chain is moved, install it, and then go to the hanger to tighten the spring and tighten it tightly until the spring is in a tight state. Then apply anti-rust oil on the chain to lubricate, so that the treatment will be no problem