Common troubleshooting methods for automobile front axle

?????Through more than 20 years of experience in the production and processing of axles, the three guarantee service experts of Fusai Axle Co., Ltd. have summarized the following common faults and solutions: 1. Technical standard of front wheel brake drum; ? Answer: The brake drum should be free of cracks and deformation. The inner diameter of the left and right brake drums on the same shaft should be no more than 1mm. The inner diameter of the brake drum after honing should not exceed 4 ~ 6mm. ? Cylindricity deviation should not be greater than 0.05mm, and the radial circle runout of the bearing bore axis should not be greater than 0.10mm. ? 2. Technical standards for the installation of kingpins and knuckles; ? Answer: The knuckle and knuckle arm should be inspected for flaws and no cracks. ? The cooperation clearance between the knuckle kingpin and the bush is 0.025 ~ 0.077mm, and ensure that the axis coaxiality deviation of the upper and lower holes is not more than 0.02mm, and the thread damage of the knuckle end should be no more than 2 teeth. The clearance between the end face of the hole and the upper end of the front shaft should not exceed 0.10mm. The main pin bearing hole wears more than 0.05mm, it should be repaired according to the graded repair size, and replace the corresponding knuckle king pin. ? 3. The gap between brake drum and brake shoe and how to adjust; ? Answer: The gap between brake drum and brake shoe is 0.15 ~ 0.30mm. ? After the brake drum is reinstalled, first adjust to prevent the brake drum from rotating, then adjust the roundness, and finally adjust the brake shoe to make the clearance between the brake drum and the brake drum appropriate. Big. ? 4. The percentage of the contact area between the brake drum and the brake shoe and the contact position; ? Answer: The contact area between the brake drum and the brake shoe should be more than 70%, and keep both ends in contact. ? 5. The method of adjusting the axial clearance of the hub; ? Answer: After installing the brake drum and the hub, when tightening the adjusting nut, the hub should be turned left and right to make the bearing in the correct position. When the adjustment nut is tightened and it is difficult to turn the hub, exit about 1/4 turn. And align the boss on the nut with the safety hole on the shaft and tighten the lock nut. At this time, there should be no sense of axial movement when pushing and pulling the hub with both hands, and the hub rotates flexibly and does not block. Finally, open the insurance film to get a good insurance.