What are the problems with Cnc Machining? How to solve these problems? This is also a headache for CNC machining, but today I am here to solve this problem for everyone:
1. How to divide the machining process?
Answer: The classification of CNC machining process is generally as follows:
(1) Tool division process
This is the process of splitting the tools you use, using the same tools to process all the parts that can be done in the part. Use the second and third knives to complete the other parts that can be completed. This reduces the number of tool changes, reduces dead time, and reduces unnecessary positioning errors.
(2) Sorting method of machining different parts position
For parts with a lot of machining content, the processed parts can be divided into several parts according to the internal shape, shape, curved surface, plane and other structural characteristics. Generally, the plane, positioning surface, and back drilling are processed first. First deal with simple geometric figures, and then deal with complex geometric figures. One is machining low-precision parts, requiring high-precision parts.
(3) Rough machining and finishing methods are used for easily deformable parts.
Deformation is generally caused by the deformation that may occur after roughing, so it is generally necessary to separate roughing and finishing processes. Therefore, when dividing the process, it should be divided according to factors such as the structure and machinability of the parts, the function of the machine tool, the CNC machining volume of the parts, the number of installations, and the production organization. It is also recommended to adopt the principle of process concentration or process distribution. These principles need to be determined according to the actual situation, but they must be reasonable.
2. What principles should be followed for the placement of the machining sequence?
Answer: The machining sequence should be determined according to the structure of the part and the condition of the blank, as well as the needs of positioning and clamping. It is important that the rigidity of the work is not compromised. Generally speaking, the sorting should be based on the following principles:
- (1) The machining of the previous process cannot affect the positioning and clamping of the next process. In addition, intermediate machining needs to be considered.
- (2) First add the inner cavity, and then proceed to the outer molding step.
- (3) It is best to connect the same positioning, clamping method or the same tool to reduce the number of repeated positioning, tool change times and the number of movable plates.
- (4) For multiple processes running on the same equipment, the process of reducing the rigidity of the workpiece must be put in the first place.
3. What should be paid attention to when deciding how to clamp the workpiece?
A: When determining the positioning standard and clamping method, there are four points to keep in mind.
- (1) Strive to unify design, process and programming calculation benchmarks.
- (2) The number of clamping times can be reduced as much as possible, and all surfaces that have been positioned and processed at one time can be treated as much as possible.
- (3) Avoid using mechanical manual adjustment procedures.
- (4) The fixture must be opened smoothly, and its positioning and clamping mechanism will not affect machining (collision, etc.) during machining. When this happens, you can clamp the fixture with a vise or a base plate.
4. How to choose the machining route
The tool path is the path and direction of the tool to the workpiece in the indexing control process. The reasonable choice of machining path is very important, because it is closely related to the machining accuracy and surface quality of the parts. The main considerations for route determination are:
- (1) Ensure the machining accuracy requirements of the parts.
- (2) Convenient numerical calculation, reducing programming workload.
- (3) Find the shortest machining route, shorten machining time, and improve machining efficiency.
- (4) Minimize the number of blocks.
- (5) In order to ensure the roughness of the contour surface of the workpiece after machining, it is necessary to arrange the final contour so that the final contour is processed continuously.
- (6) In order to minimize the loss of the tool at the contour, the path of the tool forward and backward (cutting in and cutting out) should also be carefully considered (the rapid change of cutting force will cause elastic deformation. Reason). In addition, by cutting vertically on the contour, the workpiece will not be scratched.