Sharpening method
1, people stand beside the grinder to prevent the grinding wheel from breaking and debris flying out to hurt people.
2. Let go of the distance of holding the knife with both hands, and clamp the waist with two elbows to reduce the jitter when sharpening the knife.
3. When sharpening the knife, the turning tool should be placed in the horizontal center of the grinding wheel, and the tip of the turning tool should be slightly inclined upward by about 3 ~ 8. After the turning tool contacts the grinding wheel, it should move horizontally from left to right. When the turning tool leaves the grinding wheel, the turning tool should be lifted upward to prevent the grinded blade from being damaged by the grinding wheel.
4. When grinding the cutter face, the tail of the cutter bar deviates to the left by a main deflection angle; When grinding the side of the tool pair, the tail of the tool bar is shifted to the right by an angle of the auxiliary offset angle.
5, grinding tool tip arc, usually with the left hand holding the front end of the turning tool as the fulcrum, the right hand turning the tail of the turning tool.
Extended data
Selection of grinding wheel
The characteristics of grinding wheel are determined by five factors: abrasive, particle size, hardness, binder and structure.
1, abrasives, commonly used abrasives are oxides, carbides and high hardness abrasives. Alumina grinding wheel and silicon carbide grinding wheel are commonly used in ships and factories. Alumina grinding wheel has low hardness (HV2000-HV2400) and high toughness, and is suitable for sharpening high-speed steel turning tools, of which white is called white corundum and taupe is called brown corundum.
The abrasive hardness of silicon carbide grinding wheel is higher than that of alumina grinding wheel (Hv2800 or above). Brittle and sharp, with good thermal and electrical conductivity, suitable for grinding cemented carbide. Among them, black and green silicon carbide grinding wheels are commonly used. Green silicon carbide grinding wheel is more suitable for sharpening cemented carbide turning tools.
2. Particle size: Particle size indicates the degree of abrasive particle size. This symbol is the number of holes through which abrasive particles can pass per inch. For example, a particle size of 60 means that abrasive particles have just passed through a screen with 60 holes per inch. Therefore, the larger the number, the finer the abrasive particles. The grinding wheel with small number of abrasive grains should be selected for rough turning tool, and the grinding wheel with large number of abrasive grains (i.e. fine abrasive grains) should be selected for fine turning tool. Medium soft or medium hard grinding wheels with grain size of 46-0 are commonly used on ships.
3. Hardness: The hardness of the grinding wheel reflects the difficulty of abrasive particles falling off the surface of the grinding wheel under the action of grinding force. The grinding wheel is hard, that is, the surface abrasive particles are not easy to fall off; The grinding wheel is soft, indicating that the abrasive particles are easy to fall off. Grinding wheel hardness and abrasive hardness are two different concepts, which must be clearly distinguished. When sharpening high-speed steel turning tools and cemented carbide turning tools, soft or medium-soft grinding wheels should be selected. In addition, the bonding agent and microstructure of grinding wheel should also be considered when selecting grinding wheel. Generally, ceramic binder (code A) and grinding wheel with medium structure are selected on ships and factories.
To sum up, the grinding wheel should be selected correctly according to the tool material. When sharpening high-speed steel turning tools, soft or medium-soft alumina grinding wheels with particle size of 46 ~ 60 should be selected. When sharpening carbide turning tools, you should choose soft or medium soft silicon carbide grinding wheels with particle size of 60 to 80, and you can't make a mistake between them.