First, the reason for the damage of the hanger bearing is that the lack of lubricating oil in the bearing leads to the increase of bearing wear or ablation, or the rubber ring around the bearing seat is in disrepair, fracture or fall off, which leads to the loosening of the outer diameter of the bearing and the seat hole rotation, which leads to the pulsation of the transmission shaft of the fuse frame, and leads to the fracture of the lower part of the frame, bolt fracture, bolt joint fracture and so on. Bearing damage is caused by insufficient lubricating oil in the bearing, which leads to increased bearing wear or ablation, or the outer diameter of the bearing and the valve seat hole due to disrepair, fracture or fall off, which causes the fusion frame drive shaft pulsation, resulting in the lower part of the frame fracture, bolt fracture, bolt joint fracture and so on.

2. The transmission shaft parts are damaged because of the deformation of the front and rear transmission shaft, the uranium fork of the universal joint, the convex fork of the universal joint and the key channel shaft of the expansion joint, which leads to the swing deviation of the complete set of transmission axis of the transmission shaft, or the excessive wear and loose wear of the field type universal joint due to insufficient lubricating oil; Or sliding keyway and expansion joint between the grooves loosening wear aggravation. Results The overall clearance of the drive shaft increased, axial shimmy appeared, the central hanger was impacted for a long time, and the lower part of the hanger was fractured.

Three, truck drive shaft center hander since the 1940s in the car in the beam to maintain the bearing punch (tile frame) type towel core bracket, material using section cast iron (Ma steel) casting. The pylon of this structure is only suitable for small weight reduction vehicles (some modern drive shaft center supports are made of steel plate seam welding and assembled on the middle beam, which is relatively safe). Fracture layer is easy to be produced in casting hanger due to improper technology, loose metal or porosity, brittleness of materials and other reasons. During the warranty installation of the central hanger, the improper bolt fastening method resulted in the unbalanced and uneven installation of the hanger or the assembly of the hanger cover, leading to the warping of the hanger or the hanger cover, resulting in the stress concentration fracture at a certain point, and the hanger was fractured.

As long as there is one of several factors leading to the transmission shaft center hanger damage, it will cause incalculable losses to the vehicle. For this reason, the transmission components should be checked and adjusted during the regular maintenance or warranty period of the vehicle.