Failure Analysis of End Face Seal of Floating Side Plate of Gear Pump

Melt gear pump adopts automatic compensation structure of axial clearance. The main failure form of end seal is serious wear of floating side plate, the clearance between side plate and gear end increases, and the volume efficiency of gear pump decreases. The sealing performance of the end face of the side plate depends on the following two points: 1. Compression ratio of the floating side plate; 2. Tilting moment of the floating side plate.

Through the analysis of the wear problem of floating side plate of melt gear pump, it is concluded that the overturning moment of side plate is the key factor that causes the local compression ratio of side plate to exceed the allowable value of material, and then causes serious local wear of side plate. In order to improve the sealing performance of floating side plate, the side plate structure should be designed asymmetrically to reduce the overturning moment.