The workpiece is rotated, and the diamond lathe is machined in a straight line or curve. Turning is usually carried out on a lathe, which is used to process the surface of the workpiece, cylinder, end face, cone face, forming surface and thread, etc. When the turning surface is cylindrical, the lathe tool moves in the direction parallel to the rotating axis of the workpiece. When turning the end face or the workpiece, the turning point of the cutter is moving horizontally along the axis perpendicular to the workpiece. If the motion track of the lathe and the rotating axis of the workpiece become a bevel, the cone surface can be machined. The shape of the anti-rotating body can be used to select the forming tool method or the tip rail method. During turning, the workpiece is rotated by the spindle stock of the machine tool. A tool holder is placed on the tool holder for movement. The cutting speed v is the linear velocity (m/min) of the rotating workpiece surface and the contact point of the lathe tool. Is cutting depth of each cutting and machining for the trip between appearance and finished appearance of vertical distance (mm), but when block and form turning is't vertical to the direction of the tool and workpiece contact length (mm). The amount of feed indicates the displacement of the tool in the direction of each turn of the workpiece (mm/RPM), and the amount of feed per minute (mm/min) is also available. The cutting speed is usually 25~ 60m/min, and the hard alloy diamond tool can reach 80~200 m/min. The maximum cutting speed can be up to 300 m/min with coated hard alloy turning tool.
Turning is usually divided into coarse and fine cars (including semi - fine cars). The coarse vehicle tries to improve the turning power by using large cutting depth and large feed amount without reducing the cutting speed, but the machining accuracy can only reach IT11, and the roughness of the surface is R, 20~10 micron. The semi-fine car and the fine car choose the high speed and small amount of feed and cutting depth as far as possible. The machining accuracy can reach IT10~7, and the roughness of the surface is R, 10~0.16 micron. In the high precision lathe, the precision of the diamond lathe tool, the non-ferrous metal parts, can make the machining precision reach IT7~5, and the surface roughness is R, 0.04~0.01 micrometer, which is called mirror turning. If on the cutting edge of diamond turning tool practice of 0.1 ~ 0.2 microns concave, convex, are turning slightly and put neat appearance will happen is concave and convex stripes, under the influence of diffraction of light appeared the burnish like brocade, can be used as decorative appearance, this kind of cutting is called rainbow face turning.
Turning processing, if the workpiece rotate together, tool also with the corresponding rotational speed ratio (tool rotation speed is usually several times of workpiece speed) and the workpiece rotation direction, can change the relative motion of the cutting tool and workpiece, processing out of the cross section of polygon (triangle, square, rhombus and hexagon, etc.) of the workpiece. If the diamond tool longitudinal feed together, and every turn, relative to the workpiece to rest with the addition of a periodic radial reciprocating motion, can processing CAM or other noncircular cross section appearance. The diamond tool manufacturer is introduced in the shovel tooth lathe, according to similar working principle can process certain multi-tooth cutter (such as form milling cutter, gear hob) the back knife face of knife tooth, it is called shoveling back.
