Keyway milling cutter is a kind of milling tool, and its edge diameter limit error is divided into E8 and D8. Keyway milling cutter has a small helix angle (20 degrees), groove depth, approximately straight back folding, and is similar to twist drill.
Tool setting device
Keyway milling cutter can not process plane, while end milling cutter can process plane.
Keyway milling cutter is mainly used for processing keyway and groove. Keyway milling cutter is good at keyway milling. For example, the end milling cutter of 6mm is easier to break than the keyway milling cutter of 6mm, and the keyway milling cutter can complete the task smoothly.
The cutting amount of the keyway milling cutter is larger than that of the end milling cutter.
The width of motor shaft extension keyway “F” (its tolerance is JZ) is generally not easy to guarantee. When machining keyway on end milling machine with standard straight shank keyway cutter, it is easy to exceed tolerance requirement from upper limit. Therefore, our factory uses the method of grinding the circular edge of the knife to meet the requirements of the processing keyway. The specific measures are as follows:
The milling cutter is installed on the end milling machine to adjust the longitudinal run out of the milling cutter edge to the spindle centerline to within 0.02mm.
Install a piece of cast iron (HT15-33) on the worktable, mill a cylindrical hole with depth of H + 3mm (H is the depth of keyway) on the cast iron with end milling cutter at the speed of 350-450 rpm, and then withdraw the milling cutter to remove the impurities in the hole.
Inject proper amount of kerosene and a little 200 mesh silicon carbide grinding material into the hole, adjust it into paste shape, and at the same time, apply a little grinding material on the circumference of the milling cutter.
The spindle of the milling cutter is reversed, the rotation speed is 200 rpm, and the depth of the milling cutter inserted into the hole is H + 2 mm.
Tool setting device
When machining the keyway with symmetry less than 0.1 on the shaft, the workpiece can be installed on the universal milling machine with three-jaw chuck and tail thimble. The tool setting device is accurate and fast.
The length of the cylindrical rod is the same as that of the workpiece to be processed. During the operation of the cylindrical rod, first polish it, then check the parallelism between the rod and the worktable, and then press the fixture, then press the vertical support against the rod, press the measuring head of the dial indicator on the highest edge of the milling cutter side, lock the locking screw and the base screw, record the reading of the dial indicator, and then move the tool setting device to the highest edge on the other side of the rod, Check whether the dial indicator reading is the same as above. If it is different, move the worktable until the readings on both sides are the same.
With the above method, as long as the movable gauge holder is swung to make the measuring head of the dial gauge press on the side of the keyway of the workpiece, the symmetry of the working keyway can also be directly measured. The practice in the past two years has proved that this method is effective.