Grooving: Metal chips or other foreign material in the system lead to axial cuts on the dynamic side of the seal.Expanded air bubbles (cavitation) can cause also this phenomenon.

• 沟槽:在系统中的金属屑或外部的材料在密封的运动面轴向切断；空气气泡的膨胀(气蚀)也能引起这个现象.