1. Selection of cylindrical tools and cutting parameters
According to the characteristics and processing content of parts, cylindrical machining is divided into rough machining and finish machining. In order to match with the tool holder, a diamond blade is used. Cnm090408-pr and ccmt090404-pf blades are selected respectively. Slightly larger tip, high-strength tool and low sharpness tip are suitable for rough machining. Because of its small tool angle, low tool strength and high sharpness, it is suitable for finishing. Because the outer circle of the part is relatively large, the rough turning speed is 600 rpm to ensure that the linear speed will not be too large. According to the principle of removing excess materials as soon as possible in rough machining and in combination with Sandvik tool manual, the cutting depth is 2.5mm and the speed is 0.25 mm / R. in order to ensure the balance of finish turning surface roughness, the rotating speed is 600 R / min, the cutting depth is 2.5 mm and the feed speed is 0.25 mm / R.
2. Selection of inner hole turning tool and cutting parameters
Generally speaking, when turning inner holes, holes must be drilled on the bar first. The size of the pre hole should be as large as possible, * 3 ~ 4mm smaller than the smallest inner hole on the part drawing. However, the minimum hole diameter of the part is relatively large, which is limited by the machine tool. Installation * the drill bit is 40mm and can only drill 40mm holes. Therefore, the final pre hole diameter is 40mm. Select 20m-sclcr06 tool bar according to the pre hole diameter. The diameter of the cutting rod is relatively thick and relatively hard. The diameter of the inner hole is smaller than that of the outer circle, and the speed can be increased appropriately. When turning the inner hole, the cutting depth of the inner hole is less than that of the outer circle due to the poor cutting conditions and the tool bar of the inner hole tool is usually not as rigid as that of the outer circle tool. Therefore, when the inner hole of the part is rough, if the speed is 1500 rpm, the cutting depth is 2mm and the speed is 0.2mm/min; When the speed is 1800 rpm, the cutting depth is 0.3 mm and the speed is 0.1 mm / min.
3. Selection of counterbore machining tools and cutting parameters
Countersunk holes are used for bolt installation, and the accuracy requirements are not high. Therefore, after drilling, drill a 6mm through hole with r840-0500-30-a0a bit. Since the drill bit diameter is relatively small, please refer to Sandvik tool manual and use 1500 rpm, 6 mm cutting depth and 320 mm / min. Then select r216 32-15030-ac10p flat bottom drill drills 15mm countersunk hole, which can save milling time and improve processing efficiency. Due to the large diameter of the drill bit, according to the cutting parameter manual, the speed is 800 rpm and the speed is 80 mm / min.
4. Selection of groove machining tools and cutting parameters
When processing the U-shaped open groove, it can be processed directly with a knife with the same diameter as the U-shaped groove or with a knife with a width smaller than the groove. The advantages of direct machining with a tool with the same diameter as the U-shaped groove are high efficiency and convenient programming; The disadvantage is that the size is determined by the tool and cannot be adjusted by program. The advantage of using a knife smaller than the slot width is that the size can be determined by the program and it is convenient to adjust; The disadvantage is that the efficiency is relatively low. Considering that the tolerance of U-shaped groove is 0.1, in order to ensure the machining accuracy of U-shaped groove, 10mm end milling cutter cannot be machined directly, and a milling cutter less than 10mm is required to program the milling contour. At the same time, considering the rigidity and machining efficiency of the tool, 8mm and model r216 are adopted 32-08030-ac10p end mill, and refer to Sandvik tool manual to determine the rotating speed of 3200 R / min, the cutting depth of 2 mm and the feed rate of 800 mm / min.
5. Selection of cutting parameters and holes
When machining M6 thread, 5mm drill bit shall be used to drill the bottom of the well, and then M6 * 1 tap shall be selected for tapping. When tapping, it must be ensured that the feed rate = speed * pitch, so the speed is 1000 rpm.