The name of each part of the turning tool and its function introduction

　　The turning tool is a single-edge tool. There are many types due to the different shapes of the turning work, but the names and functions of its parts are the same. A good turning tool must have a rigid handle and a sharp blade. The blade angle of the turning tool directly affects the turning effect. The material of the turning tool and the workpiece material, and the angle of the blade are also different. Turning tools for lathes have four important angles, namely front clearance angle, side clearance angle, back bevel angle and side bevel angle.

　　1 Front clearance angle

　　The angle inclined downward from the nose to the inside of the tool is the front clearance angle. Because of the front clearance angle, a space is formed under the working surface and the nose, so that the cutting action is concentrated on the nose. If the angle is too small, the tool will rub on the surface, and a rough surface will be produced. If the angle is too large, the tool is prone to tremor and the nose is broken and cannot be polished. When installing a turning tool with a tilted middle handle to grind the front clearance angle, the tilt angle of the handle needs to be considered. The angle of high-speed steel turning tool is about 8~10 degrees, and that of carbide turning tool is 6-8 degrees.

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　　 2 side clearance angle

　　The angle at which the side of the cutter inclines from the cutting edge to the inside of the cutter is the edge clearance angle. The edge clearance angle creates a space between the work surface and the knife side, so that the cutting action is concentrated on the cutting edge to improve cutting efficiency. The angle of high speed steel turning tool is about 10~12 degrees.

　　3 rear bevel

　　The angle from the nose of the knife to the handle of the knife from the top of the knife is the back bevel. This angle is mainly to guide chip removal and reduce chip removal resistance. For cutting general metals, high-speed steel turning tools are generally 8 to 16 degrees, while carbide turning tools are negative or zero degrees.

　　 4-sided bevel

　　 is inclined from the cutting edge to the other side from the top surface of the tool. The angle formed by the inclined surface and the horizontal plane is the side bevel. This angle is the angle at which the chips can be separated from the work, so that chip removal is easy and effective turning is obtained. For cutting general metals, the angle of the high-speed steel turning tool is about 10~14 degrees, and the carbide turning tool can be positive or negative.

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　　 5 knife end angle

　　 The angle between the front end of the blade and the handle perpendicular to it. The function of this angle is to maintain a gap between the front end of the blade and the workpiece to avoid friction between the blade and the workpiece or scratch the processed surface.

　　 6 cut corners

　　 The angle between the front end of the blade and the shank perpendicular to it, and its function is to change the thickness of the cutting layer. At the same time, the cutting edge angle can also change the force direction of the turning tool, reduce the feed resistance and increase the tool life. Therefore, in general rough turning, a turning tool with a larger trimming angle should be used to reduce the feed resistance and increase the cutting speed.

　　7 nose radius

　　Improvement and development of tool materials is one of the important issues in the development of metal processing today, because good tool materials can effectively and quickly complete the cutting work and maintain a good tool life.

　　 The arc radius of the highest point of the blade. The nose radius is large and strong, and it is used for large cutting depth, but it is prone to high frequency vibration.