国产老熟女伦老熟妇露脸-四川少妇大战4黑人-又色又爽又高潮免费观看-精品一区heyzo在线播放-亚洲精品久久久久成人2007

Optical curve grinder is used to grind precision and complex surfaces, including straight lines, arcs, and curves. During the grinding process, the workpiece and grinding wheel can be magnified 50 times by an optical system and projected onto a screen. During work, the operator can observe the grinding wheel processing along the workpiece surface on the screen at any time. The movement of the workpiece can be manually operated or controlled by a DC motor to achieve the purpose of processing the surface.