1, Directly find the centering clamp
This is a method of clamping the position of the workpiece directly on the machine tool using a dial gauge, a scribing disk or a visual inspection.
2, Scribing to find the centering clamp
In this method, the center line, the symmetry line and the machining line of each surface to be processed are drawn on the blank according to the part drawing, and then the workpiece is mounted on the machine tool, and the clamping position of the workpiece on the machine tool is corrected according to the line.
This type of clamping method has low productivity, low precision, and high technical requirements for workers. It is generally used for machining complex and cumbersome parts in single-piece small batch production, or where the blanks have large dimensional tolerances and cannot be directly clamped by clamps.
3, Clamping fixture
The fixture is specially designed according to the requirements of the machining process. The positioning component on the fixture enables the workpiece to quickly occupy the correct position relative to the machine and the tool. The positioning accuracy of the workpiece can be ensured without correction, and the productivity of the fixture is high. The positioning accuracy is high, but special fixtures need to be designed and manufactured, which are widely used in batch and mass production.
Precautions for clamping in machining:
1. All the clips are horizontally long and short.
2. Vise clamping: The clamping height should not be lower than 10 mm. The height of the clamping and the processing height must be specified when machining the workpiece. The processing height should be about 5 mm above the plane of the vise, in order to ensure the firmness without damaging the vise. This type of clamping is a general clamping, and the clamping height is also related to the size of the workpiece. The larger the workpiece, the higher the clamping height.
3. Plywood clamping: The pallet is coded on the workbench, and the workpiece is screwed on the clamping plate. This clamping is suitable for workpieces with insufficient clamping height and large processing force. Generally, medium and large workpieces have better effect.
4. Code iron clamping: When the workpiece is large, the clamping height is not enough, and the bottom wire is not allowed to lock, the code iron is used for clamping. This kind of clamping needs to be double-mounted, first code the four corners, process the other parts, and then code the four sides to process the four corners. When the secondary clamping is done, do not let the workpiece loose, first loosen the code. You can also code both sides and process the other two sides.
5, The clamping of the cutter: the diameter of 10mm or more, the clamping length is not less than 30mm; the diameter of 10mm or less, the clamping length is not less than 20mm. The tool should be clamped firmly to prevent the knife from being inserted directly into the workpiece.