Processing method of double side grinder:
1. Dry grinding: only a small amount of lubricating additive is applied on the surface of lapping tool during grinding. In the grinding process, the sand particles are basically fixed on the lapping tool, and its grinding function is mainly sliding grinding. The productivity of this method is not high, but it can achieve high machining accuracy and small surface roughness (ra0.02 ~ 0.01 μ m).
2. Wet grinding: in the grinding process, the abrasive is coated on the lapping tool, and the dispersed sand particles are used for grinding. In addition to sand, there are kerosene, engine oil, oleic acid, stearic acid and other substances in the abrasive. During the grinding process, some sand particles exist between the lapping tool and the workpiece, as shown in Fig. 8-12b. At this time, the sand grain is mainly used for rolling grinding with high productivity, and the surface roughness is ra0.04-0.02 μ m, which is generally used for rough machining, but the surface is generally dull.
3. Soft abrasive grinding
In the grinding process, chromium oxide is used as the abrasive to coat the working surface of the lapping tool. Because the abrasive is softer than the lapping tool and the workpiece, the abrasive is suspended between the workpiece and the lapping tool during the grinding process. The chemical interaction between the abrasive and the workpiece surface is mainly used to produce a very soft oxide film, and the film at the convex point is easily abraded by the abrasive.