Wet grinding method can be divided into research, research and semi-dry grind three categories. ① wet grind: grinding, also known as sand deposited, the continuous filling or depressed center cutting wheel coating liquid abrasive surface grinding, abrasive between the workpiece and the lap constantly sliding and rolling to form a cutting motion. Wet research generally used for rough grinding, abrasive powder used coarse granularity in W7. ② Dry RESEARCH: also known as embedded sand grinding, pressing the abrasive embedded in the uniform surface layer of the lap, the polishing lap only the auxiliary material coated with a small amount of fat stearate and the like. Research commonly used in dry fine grinding, fine grit size used in the W powder grinding machine. ③ semi Research: Research similar wet, the use of abrasive grinding paste is a paste. Either by hand polishing, polishing may be performed on the machine. Workpiece by other processing methods must first be obtained in a high precision before the pre-polishing, polishing the left margin is generally 5 to 30 microns.
Lap is shaping the workpiece grinding tools, but it is also the carrier of abrasive hardness should be less than the hardness of the workpiece, but also some wear, often made of gray cast iron. Wet grind lap ferrite microstructure dominated; dry grind lap uniform and fine pearlite places as the matrix. The following grinding M5 concrete cutting discs thread and small parts of complex shape, commonly mild steel lap. When grinding holes and soft metal materials, mostly made of brass, copper lap. Lap should be sufficiently rigid working surfaces have a high geometric precision. Lap grinding and cutting process is also subject to wear, such as operating properly, its accuracy can be improved, so that the processing accuracy of the workpiece can be higher than the lap of the original accuracy.
To correctly handle abrasive grinding trajectory is to improve the quality of an important condition. In surface grinding, the general requirements: ① workpiece relative to the movement of the lap, to try to ensure that similar grinding stroke length of each point on the workpiece; ② workpiece trajectory evenly throughout the surface of the lap, lap facilitate uniform wear; ③ sports changes in the curvature of the trajectory to be small in order to ensure smooth movement of the workpiece; ④ workpiece trajectory took a little premature to avoid repeated periodically. Pictured common plane grinding trajectory. In order to reduce the thermal cutting, grinding generally low under low pressure conditions. Coarse stainless steel cutting wheels grind pressure does not exceed 0.3 MPa, lapping pressure generally use 0.03 to 0.05 MPa. Coarse grind speed is generally 20 to 120 m / min, lapping speed generally take 10 to 30 m / min.
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