When pulling and resetting, first carefully observe the damage of the vehicle and carry out necessary tests.
The deformation of car body, cab and engine room can be detected by diagonal measurement. According to the test results, it can be determined which part is the main deformation part and how much deformation. Which part is the secondary and subsidiary deformation part?
Because the position and direction of the external force on the car in collision are different, the force propagates differently in the car body and the deformation is also different. According to the deformation characteristics and degree, the pulling position and the applied force can be selected.
For small local deformation, the deformation can be recovered by applying a force in the opposite direction to the original force at the key position.
However, it is not appropriate to use a little support for the large area and multiple collisions of the car body. First of all, excessive tension may cause the plate to break. Secondly, although the deformed part has been temporarily corrected, the undeformed part will still be deformed or internal residual stress under the action of external force. Due to the relaxation of internal stress, the vehicle has new deformation in use. Therefore, special tools should be used for broaching, and external forces should be applied in multiple points, directions and differently, and the deformation can be recovered while measuring, so as to ensure that the undeformed part is not stressed, and timely heating and beating can make the deformation recovery just right.
For local collision and cab damage that does not affect the deformation of the skeleton, most of them can be corrected by knocking. If necessary, use some special tools, such as crane's beak hammer and special shaped pad iron. If the bone has been deformed by impact, the bone correction and shell correction should be combined and implemented simultaneously. If the housing is easy to disassemble, it can be calibrated separately. If the cab impact is very serious and cannot be corrected directly, it can be partially disassembled and corrected. Open the original solder joint with hand electric drill or hand grinding wheel, and then remove the outer layer with hacksaw or gas cutting. When the deformation range is large, the outer layer can be removed, corrected separately and assembled uniformly. During leveling, attention should be paid to the cooperation between components and the shrinkage and deformation of materials during welding to avoid difficulties in subsequent installation and configuration.