In the process of preparation of metallographic sample, pre grinding, polishing and grinding are the indispensable procedures. This machine YMP-2A four speed polishing and grinding machine is produced with PPC sewage collection plate and cover and is the latest product with a new and beautiful appearance. The machine is durable, and very convenient for maintenance,the motor is DC brushless motor,when using, only need to replace the grinding disc or Polishing disc, can perform a variety of sample for the coarse grinding, fine grinding, dry grinding and wet grinding, and polishing, and so on various process. To increase the production of different sample request, the diameter of the machine's grinding and polishing disc are larger than domestic similar products, can have more different line speed choices in work face, can increase the effective work face 20%- 30%, at the same time, can improve the quality of grinding and polishing of the sample, and the sample preparation efficiency. And the machine steady running, low noise, it is a very ideal and perfect function kind of metallographic sample preparation equipment. Main parameters Diameter of the polishing and grinding disc: 230mm Diameter of the abrasive paper: 230mm Rotational speed: Low speed 300/500, High speed 600/1000 Motor:YSD802-8/4, 0.25/0.37KW, 380V External dimension: 757x623x320mm Net weight:58kg