The frame is the foundation of a car. In addition to the requirements of the straightness and parallelism error, the dimensions of various installation holes on it are required to be accurate to ensure that the axis of each assembly from the engine to the drive bridge is the same; and the axis of the installation holes of the parts of the left and right sides should be the same axis and the axis of the frame is kept vertical. Directly, it can make the car run in a straight line when the machine parts are in normal state. Because of improper use and maintenance, the frame of the heavy truck parts in Baotou is prone to bending and twisting, loosening or even breaking of rivets, so that the installation position of the machine parts is abnormal, resulting in a variety of faults.

(1) the main cause of bending deformation of Baotou Bei Ben heavy truck fittings frame.

1) bending deformation occurs mainly in the middle part of the longitudinal beam between the front axle and the rear axle. As a result of overloading or high speed, the additional impact load is caused by the additional impact load over the fatigue strength of the longitudinal beam, and the result of the length action will break up.

2) the distortion often occurs when the road is uneven, the vehicle wobble and wobble around the car. If the load is not evenly distributed in the car, or the part of the steel plate spring in the north of Baotou is invalid, it makes the body skew and distorts the frame.

3) the frame was deformed due to collision and accident.

(2) the inspection and repair of the deformation of the frame.