Common Accidents and Precautions in the Removal and Installation of Tower CRANE
1. Common accidents
1 The accident in the overhead cylinder operation has been introduced before, and is repeated here.
2 When lifting the heavy arm, the suspension point is not allowed, and the choice of the hanging rope is wrong, causing the lifting arm to be unstable, causing the hanging rope to leave the hook to cause a fall injury.
3 The wire rope binding method is not correct, resulting in the steel wire rope hanging to the pull rod connection pin during the process of decentralized drawing rod. Due to the sudden weightlessness of the neutral effect of the pull rod, the large swing width of the tower crane caused a collapse accident.
4 When installing a tower cap or balance arm, the crane does not bend up or down according to regulations, causing the tower to lean back and cause an accident.
5 Dismantling: The focus is on demolition methods, procedures, auxiliary machinery tools, organization and deployment of labor force, environmental conditions and the disintegration of protection and components, transportation, exit, etc.
Demolition and installation programmes are prepared in accordance with their requirements and must be specified.
Do not strictly follow the demolition and assembly procedures, especially when removing weight, first remove the heavy arm and later remove the weight, causing the tower suspension center to move backwards and capsize.
2. Preventive Measures and Methods
Before removing the connection between the heavy arm root and the over-joint of the tower body, use a steel wire rope of 12.5 mm or 25 mm to tighten the tower body and the forearm root, and when the heavy arm is smoothly separated from the back of the tower, In order to remove the wire body or put down the lifting arm(the balance arm is the same).
The spacing L of the lifting point should be satisfied: 8M ≤ L ≤ 15mm, the angle of the wire rope is generally not more than 90O, and when installed, Make the lifting point position in the lifting arm and balance state and make a permanent standard position
2 The wire rope is generally bound by the <UNK> 22.5 mm long 9 ~ 11 M "walking horse" method so that when the pull rod is decentralized, the wire rope can slide naturally to the specified position along the pull rod.
When installing the tower cap or balance arm, work strictly according to the angle of upturn or downswing specified in the manual.
Before removing the counterweight Heqi's heavy arm balance arm, the rotary support must be connected to the standard joint with a bolt or pin shaft before the operation can be carried out.
It is strictly forbidden to remove the lifting arm without removing the weight. Keep a piece of the corresponding weight in strict accordance with the specifications. In addition, lifting arm removal is not allowed to allow the balance arm to be suspended overnight.
