Overhaul of Transmission Shaft Parts

Overhaul of transmission shaft tube, spline shaft and spline sleeve

(1) Repair of shaft tube. Shafts are often damaged by bending, dents, and weld cracking. Normally, the drive shaft shaft tube is supported on two "V" shaped blocks to rotate, and checked with a dial indicator.

 

Repair of spline shaft. Spline shafts often suffer from spline wear, key teeth with lateral cracks and other damage. Spline shaft key tooth crack, its size does not exceed the root circle 1. At a depth of 5 mm, it can also be repaired by vibrating surfacing. When the spline shaft (or universal joint fork) is worn or cracked seriously, it should be replaced. Check on the lathe that the swing of the shaft of the drive shaft assembly cannot be greater than 1. 5 mm. The total length of the measurement shall not be less than the nominal size of 10 mm, and those with conditions shall carry out a dynamic balance test.

 

Overhaul of cross shaft

Cross shaft journal wear is a common form of damage. When the vehicle is traveling, the direction of torque transmission is constant, so the wear on the bearing seat hole of the cross axle journal and the universal joint mainly occurs on the side of the bearing surface. When the cross axle journal equipped with needle roller bearings is severely worn, grooves are generated, which are loose and loud. The reasons for this phenomenon are as follows:

 

①According to the original design requirements, the needle bearing should be lubricated with gear oil, and the grease should be changed during use. Due to the high viscosity of the grease, the needle of the bearing is not easy to rotate, and the role of the rolling bearing is lost, so that the groove on the journal surface is generated.

 

②The deformation of the bearing sleeve (steel bowl shell) makes the needle roller difficult to rotate. During assembly, the nut on the tile cover was not tightened to the specified torque of 45 to 50 N · m. If the tightening torque is too large, the bearing sleeve is clamped and deformed, the needle roller is not easy to rotate, and the groove appears after long-term use. Some agricultural vehicle drive shaft bearing housing holes are integral. During the maintenance and assembly process, the bearing sleeve and the seat hole are too tight (the interference amount is greater than 0.01 mm), and even hit the outside of the universal yoke bearing seat hole to shrink the seat hole. If the shrinkage of the seat hole is uneven, the bearing sleeve will be deformed, affecting the rotation of the needle roller, and the cross shaft journal will be ground out of the groove.

 

③The needles of the needle roller bearings are messed up during assembly, the diameter of the needle rollers is different, the length is not the same, or the needle rollers are grooved at the bottom of the bearing sleeve, etc. Which will affect the normal rotation of the needle rollers and increase the wear of the cross shaft journal .

 

Overhaul of intermediate support of transmission shaft

The intermediate support of the transmission shaft often has problems such as journal and bearing wear, oil seal damage, and bearing bracket gasket aging. The coordination of the shaft journal of the drive shaft and the intermediate support bearing is generally -0.020 to +0.020 mm. If the fit clearance exceeds 0.04 mm and the journal wear at the contact with the oil seal exceeds 0.25 mm, surfacing, bushing, chrome or iron plating should be used for repair. After repair, check the coaxiality, the swing difference should not exceed 0. 20 mm. The roughness of the journal surface of the oil seal contact should not be less than 0.8 μm. The rubber gasket of the bearing bracket should be replaced when it is aging, and the new one should be replaced if the bearing is seriously worn.

 

The above is the repair part of the transmission shaft parts. Mastering the above points can help you solve some problems of the transmission shaft in advance.