Common fault diagnosis and troubleshooting methods of universal coupling

　　The common feature of universal joints is that the angular compensation is large, and the angle between the two axes of universal joints of different structure types is different, generally ≤5°-45°.The universal coupling utilizes the characteristics of its mechanism to make the two shafts not on the same axis, and when there is an angle between the axes, it can realize the continuous rotation of the connected two shafts, and reliably transmit torque and motion.The universal coupling is characterized by its large angular compensation capability, compact structure and high transmission efficiency.

　　Common fault diagnosis and troubleshooting methods of universal coupling
　　(1) First check whether the connecting bolts of the universal joint flange plate are loose, and tighten them as appropriate.
　　(2) If the fault is still eliminated, remove the drive shaft assembly and perform a balance test on a balancing machine. If the unbalance is very poor, balance compensation should be performed.
　　(3) If the abnormal noise and vibration are still eliminated, check whether the expansion joint is installed to the standard mark. If the installation is correct, support the car body and start the engine to run at low idle speed. If the universal coupling swings Large, it can be used to measure the deflection position, direction and amount of deflection with a scribing needle. If the two ends of the drive shaft are not straight or bent, a soft metal that matches the shaft tube should be cushioned on the pressure strip for cold pressure correction.
　　(4) If the noise is not caused by the above reasons, check whether the universal joint shaft tube has bumps and depressions, and whether the balance sheet is missing.Loss of the balance sheet requires re-welding the same balance sheet at the original solder joint position.If the universal joint shaft tube has obvious depressions and the universal joint itself loses balance, the spline shaft and universal joint fork should be cut off on the lathe, and an inner diameter of the shaft tube should be inserted into the shaft tube. The thin mandrel is repaired by hammering in the depression.Then cross-weld the cut spline shaft and universal coupling to the original position.In order to ensure the quality of repair, the shaft tube should be placed on a special bracket when welding, and the number of points should be welded symmetrically on the circumference, and then the deflection should be corrected, and then welded along the circumference after correction.After cooling down after welding.Check again, and re-welding should be done if the swing difference is too large.The process is more complicated.If the universal joint is dented and damaged in a large area, the drive shaft needs to be replaced.