People in the industry and our friends in the cutting production industry should know that grinding wheel grinding is a method of cutting workpiece with grinding wheel as cutting tool on grinder. Moreover, there are many skills and characteristics of this method. I don't know how much you have mastered. Now let's learn about the application of grinding wheel in stone grinding!
1) Because the abrasive grains of the grinding wheel have high hardness and heat resistance, materials with high hardness can be processed by grinding, such as quenched steel, cemented carbide, etc.
2) The characteristics of grinding wheel and grinder determine that the grinding technology system can carry out uniform micro cutting, because the hydraulic driver is adopted, the general AP = 0.001 ~ 0.005mm; The grinding speed is high. Generally, the grinder with v = 30 ~ 50M / s has good rigidity; Therefore, grinding can obtain economically high machining accuracy (IT6 ~ it5) and small surface roughness Ra = 0.8 ~ 0.2m. Grinding is one of the main methods of parts finishing.
3) Due to intense friction, the temperature in the grinding area is very high. In this way, the workpiece may produce stress and deformation, which may affect the surface of the workpiece. Therefore, a large amount of coolant needs to be injected to reduce the grinding temperature. The coolant also plays the role of chip removal and lubrication.
4) The radial force of grinding wheel is very large. This will cause the elastic avoidance of the machine tool grinding disc workpiece system, resulting in the actual cutting depth being less than the nominal cutting depth. Therefore, at the end of grinding, it is necessary to carry out light grinding without a knife to eliminate errors.
5) After the abrasive particles become blunt, the grinding force is also increased, the abrasive particles are broken or fall off, and the sharp tip appears again. This characteristic is called "self sharpening". The sharpness can be grinded normally within a certain time, but after a certain working time, it needs to be repaired manually to avoid vibration, noise and damage to the surface quality of the workpiece caused by the increase of grinding force.
The grinding wheel has high hardness and toughness. Commonly used abrasives are alumina (also known as corundum) and silicon carbide. It is a porous object formed by bonding a large number of fine and hard abrasive particles and adhesives. The abrasive directly undertakes the cutting work and should be sharp. The alumina based abrasive has high hardness and good toughness, which is suitable for steel grinding. Silicon carbide based abrasive has high hardness, sharpness and good thermal conductivity, but it is very brittle. It is suitable for grinding cast iron and cemented carbide.
For the same abrasive tools, the coarse abrasive particles are used for rough grinding, and the fine abrasive particles are suitable for fine grinding. According to their thickness, the surface roughness and processing efficiency of the workpiece after processing are also different. The coarser the abrasive particle, the smaller the particle size.
The adhesive of grinding wheel plays the role of bonding abrasive. Ceramic adhesives are commonly used, followed by resin adhesives. According to the choice of adhesive, the corrosion resistance, strength, heat resistance and toughness of grinding wheel are affected. Wear resistant electrode
The more firmly the abrasive grains of the grinding wheel are bonded, the more difficult it is to fall off the grinding wheel, which is called the hardness of the grinding wheel. In other words, the hardness of the grinding wheel refers to the degree that the abrasive particles on the surface of the grinding wheel are not easy to fall off due to external force. Things that fall off easily are called soft, and vice versa. The hardness of grinding wheel and abrasive are two different concepts. The grinding time of the soft edge of the workpiece can be prolonged after grinding. In other words, the grinding wheel with firm adhesion (grinding wheel with high hardness) can be selected. On the contrary, it shall be checked before installation to ensure that there are no cracks and other defects; In order to make the grinding wheel work stably, the grinding wheel with low hardness is suitable for grinding workpieces with high hardness. The grinding wheel works at high speed. In order to ensure safety, the action balance test shall be carried out before use.
After the grinding wheel has been working for a certain time, it needs to be trimmed to restore the cutting ability and correct geometry. The gap on the surface will be blocked by chips, the acute angle of the abrasive will become blunt, and the original geometric shape will be deformed. The grinding wheel needs to be trimmed with a diamond pen.
The above introduction is the application method of grinding wheel in stone grinding. If you need to know more, you can contact us at any time!