How much do you know about the flywheel bearing?

Function of flywheel bearing
Flywheel bearing is the guide bearing of the first shaft of the transmission, which is used for positioning and guiding. The guide bearing is installed on the hole behind the crankshaft or in the center of the flywheel, which is used to guide and prevent the radial run-out of a shaft when the clutch is disengaged. The torque of the engine passes through the flywheel, clutch housing, pressure plate and clutch driven plate to reach a shaft.

When activated, the switching time of automatic racing gearbox is very short, and this flywheel bearing is allowed to be exposed to very high speed gradient. This also brings special requirements to bearings and bearing lubricants. Choosing the right bearing design, grease and even coating at this position is very important for the robustness and reliability of the solution.

Identification method of flywheel bearing damage
First, make a visual inspection, check whether the teeth of the ring gear are worn or dented, and check whether the flywheel end face has ablation, grooves, warpage and cracks, etc. If so, repair or replace the flywheel.

Check the bearing on the flywheel again. Turn theflywheel bearing by hand and apply force in the axial direction. If there is blockage or obvious clearance, replace the bearing.

Finally, check the circular runout of the flywheel end face. Install the dial indicator on the engine block, with the dial indicator needle against the outermost ring of the flywheel, rotate the flywheel, and measure the circular runout of the end face of the flywheel, which should be less than 0.1 mm.. If the end face runout exceeds the standard, the flywheel should be grinded or replaced.

The connecting bolts should be replaced every time the flywheel is removed. When the flywheel is installed on the crankshaft, it should be tightened diagonally by the specified torque.

After the flywheel bearing is damaged, there will be some noise and sound when starting. After a period of excessive wear, the noise will decrease or disappear, which will seriously affect the service life of the first shaft bearing of the gearbox, resulting in loose bearings for a week. In severe cases, the gearbox will have abnormal noise when it is in neutral and the noise will disappear when the clutch pedal is pressed. In view of this situation, it is necessary to replace it, that is, the gearbox assembly needs to be disassembled and the repair cost is very expensive.

During the installation of the flywheel bearing, the factors causing the sticking result include the following aspects:

1, The flywheel bearing itself processing and manufacturing factors;

2. Factors of machining and manufacturing the center hole of flywheel;

3. Factors that lead to material deformation due to bolt tightening torque;

4, the factors of the way and method of assembling the flywheel bearing, etc.

Solution:

1. During field operation, it is found that the flywheel bearing installation card is lagging behind, so the bearing is withdrawn, and the center hole of the flywheel is grinded by reamer or grinding wheel. Reinstall the flywheel bearing and check whether it is normal. When a large number of bearings are stuck, it brings a very difficult problem.

This measure has the following shortcomings: the grinding amount cannot be accurately controlled; When withdrawing from the bearing, it is easy to cause the bearing to be abnormal or even damaged; Increase of manual workload and decrease of work efficiency; The consistency of bearing assembly becomes worse.

2. Change the machining process requirements of the center hole of the flywheel. The tolerance requirement of the center hole of the flywheel is (0, -0.03)mm, the essence of which is to ensure that the flywheel bearing is an interference fit after installation. However, after the six bolt holes around the central hole are tightened, it causes deformation, which leads to the decrease of aperture and excessive interference. Coupled with the uneven deformation caused by the tightening torque, the flywheel bearing is stuck. The flywheel bearing has a bearing seat, which will not cause the clutch shaft to fall out when it expands and contracts.

After docking verification by all parties, in terms of technical requirements, the pilot hole is increased from φ Φ52M7 to φ Φ52H7, that is, it is increased by 0.03mm to offset the deformation of the central aperture. Not only ensure that interference fit, but also eliminate the sticking in the installation proces. Put an end to a series of adverse effects.

3. Actual improvement and innovative effect: After improving the machining process of the center hole of the flywheel, there has not been a case of sticking in the half-year period.

If you need any brand bearings or any models of bearings, please contact me!

Contact: Bella
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