1. Unstable tipping
Theoretically, the fundamental reason for tipping is that the torque on the truck crane is unbalanced, and the overturning torque exceeds the stabilizing torque. Look from actual condition, there are a variety of factors that will cause overturning torque, in addition to overload and misoperation, there are also the inertia force of wind, improper working speed, leg support infrastructure degradation, the deformation of the end of arm frame, or some other random and uncertain factors, various factors are often intertwined. The influence of these non-weight overloads causes the increase of the complexity of the actual operation of the crane, which makes it difficult to judge correctly.
2. Arm frame failure
Arm frame is one of the main bearing metal structures of a truck crane. When lifting, under pressure and the joint effects of bending, the failure of strength, stiffness and stability can cause arm frame structure being damaged. The failure of the amplitude mechanism can also cause the arm frame to fall, and the severity of its consequences is equivalent to objects falling.
3. Get an electric shock
When a truck crane is working near a power line, it can cause electric shock when it touches a charged body or is too close to it.
Due to limited job site conditions, the space between truck crane and other equipment or between crane and other architectural structure lack of enough safety distance. When rotary, the metal structure, counterweight, or hanging load of the rotating parts will squeeze each other and cause damage to personnel.