The car clutch pressure plate is a metal disc. In a normal state, it is closely combined with the car clutch plate as a whole, rotates with the engine and transmits the power to the gearbox. When the clutch pedal is pressed, the clutch pressure plate is separated from the clutch plate, which cuts off the power output of the engine and gears can be shifted. When the clutch pedal is lifted, and the clutch pressure plate is combined with the clutch plate again to transmit power.
There are generally two types of clutch pressure plate components: with coil spring and with diaphragm spring. The difference is that they press the pressure plate and leave the clutch-driven plate in different ways.
It is to press the clutch driven plate onto the flywheel with sufficient force, so as to effectively transmit the engine torque, and the driven plate stops rotating when it is separated from the clutch.
The shape of the clutch pressure plate is complex, which requires good heat transfer, high friction coefficient and wear resistance. Therefore, it is usually cast from gray cast iron HT200. The metallographic structure is pearlite structure, and the hardness is HB170 ~ 227. In addition, a small number of metal elements (such as nickel, iron, manganese alloy, etc.) can be added to enhance its mechanical strength.
1. Inspection of end face runout of the pressure plate
Fix the pressure plate on the mandrel and check its end face runout with a dial indicator. The service limit is 0.2mm. If the riveting contact of the pressure plate is damaged or doesn't rivet, the pressure plate shall be replaced.
2. Check of diaphragm spring height
If the diaphragm spring height changes, it indicates that the diaphragm spring has insufficient elasticity and must be replaced. The height of the diaphragm spring can be checked with a caliper, and the difference from the standard height shall not be greater than 0.5mm.
3. Inspection of wear of diaphragm spring small end
Check the contact wear trace between the small end of the diaphragm spring on the clutch pressure plate and release bearing with a caliper, and the depth shall not be greater than 0.6mm.