How to extend the service life of drive shaft bearings

The series of loaders in my country are similar in structure. The two drive shafts of the variable speed pump, steering pump and working pump are generally driven by gears connected to the pump wheel of the torque converter. Due to the high position of the drive shaft bearing, the splash lubrication conditions are very bad, and the service life of the bearing is far from reaching the design requirements. So how can we increase the service life of the loader drive shaft bearing?

1. The oil level in the gearbox must be checked frequently during use to ensure that the oil level is close to the upper limit position, that is, the oil level should be more than less than the upper limit. If the oil level is too low, the splashing force of the oil will be greatly reduced. At the same time, the volumetric efficiency of the variable speed pump will be reduced accordingly, so that the amount of splashing oil for lubrication and cooling will also be reduced, and the lubrication of the bearing will be further deteriorated. Since the oil seal of the output shaft of the gearbox is prone to leakage, many operators often wait until the oil level of the gearbox drops to the point where it is difficult to shift gears. This is not correct, and care should be taken to avoid this.

2. The wear of the drive shaft bearing of the hydraulic pump and the damage of the flat key or spline connection of the hydraulic pump are mutually cause and effect, that is, the wear of the bearing causes the flat key and the flat keyway to produce fretting wear, and the additional load of fretting wear accelerates the bearing Abrasion, or even vibration in severe cases, will loosen the installation bolts of the hydraulic pump, which will bring great trouble to maintenance. If 2 to 3 flat key grooves are machined in the inner hole of the drive shaft of the hydraulic pump, it will be helpful for maintenance.

3. Regularly check the system pressure of each hydraulic pump and the effective speed of the governor of the fuel injection pump assembly of the diesel engine. There have been cases in which bearings and hydraulic pumps were damaged prematurely due to excessively high system pressure or excessively high operating speed of the governor.

4. In the structural design, if the splash lubrication of the drive shaft bearing is changed to fixed-point lubrication, the reliability of lubrication and the life of the bearing can be greatly improved.