Matters needing attention in large-scale machining and quality requirements

There are many problems that need to be paid attention to when machining large-scale machining. Therefore, the machining staff should fully understand these problems that need attention before operating their workpieces, so as to better shorten the machine. Processing time, reduce the problems encountered in the machining process, and improve the quality of the workpiece.
Problems needing attention in large-scale machining
1. When the workpiece is too high, you should use knives of different lengths for roughing, and then use a knife to remove the remaining material.
2. Flat-bottomed knives should be used when processing the plane, which can effectively reduce the processing time. If there is an inclination and it is an integer, you should use an inclination knife for processing.
3. For large-scale machining materials with high hardness, up-milling should be selected; for materials with low hardness, down-milling should be selected; for finishing, up-milling should be used, and for finishing, down-milling should be used.
4. Large-scale machining tools have good toughness, low hardness, and are suitable for rough machining; tools have poor toughness and high hardness, and are suitable for finishing.
Issues that need attention in the selection of large-scale machining parts and fixtures
1. The clamping method of mechanical parts processing should reasonably choose the positioning datum and clamping plan. When we choose
When setting our benchmarks, we should follow the two principles of 'unification of benchmarks' and 'coincidence of benchmarks'.
2. In large-scale machining, all surface processing can be completed in one positioning and clamping as much as possible. Therefore, it is necessary to choose a positioning method that can be easily processed on each surface of the workpiece.
3. When determining the position of the workpiece on the worktable, the influence of the processing at each position, the length of the tool and the stiffness of the tool on the processing quality must be considered.
4. Fixtures used in machining should be assembled from common parts as much as possible, and can be adjusted, which can effectively shorten the production preparation cycle.
Problems to pay attention to when arranging large-scale machining sequence
(1) To arrange the machining sequence, the basic principles of 'face first, hole second' and 'rough first then fine' must be followed.
(2) Determine the tool point and tool change point. Once determined, it is not suitable for replacement.
(3) Processing according to the centralized process of the tool can better avoid the repeated use of the same tool and reduce the number and time of tool replacement.
(4) For the hole system with very high coaxiality requirements, all the holes in the hole system should be processed after one positioning, and then the hole system in other coordinate positions can be processed, which can effectively eliminate the error caused by repeated positioning , Improve the coaxiality of the hole system.