The scroll wrap is the main movement part of compressor, only have the tooth, have no abrasion, thus the life is longer, so this is free maintenance compressor.
涡旋压缩机主要运动件涡盘只有啮合没有磨损，因而寿命更长，被誉为免维修压缩机。
2
On the other hand, a hard-bristled brush, coupled with vigorous brushing can result in recession of the gums and the abrasion of tooth enamel and exposed root surfaces.
另一方面，硬毛牙刷刷，刷的积极可能导致经济衰退的牙龈和牙齿的珐琅质磨损，暴露根耦合表面。
3
Wedge-shaped defect is an abrasion that caused by long-term abrasion in tooth cervical.