spherical lapping

例句：

1. 1.The engineer used a spherical lapping machine to smooth the surface of the metal.
   工程师使用球面磨光机来平滑金属的表面。
2. 2. The car was polished to a spherical lapping finish.
   汽车被打磨到球面抛光的完成度。
3. 3.The technician performed a spherical lapping operation on the gears.
   技术员对齿轮执行了球面磨光操作。