The overall planning of the production and processing process flow refers to the entire process technology, and cannot be distinguished by the characteristics of a certain process flow and the production and processing of a certain surface layer. For example, there are some precise positioning reference points that need to be produced and processed very well in the semi deep processing stage and even in the initial processing stage. Sometimes, in order to better prevent dimension chain calculation, some semi deep processing of primary and secondary surfaces can also be allocated in the deep processing process. After confirming the production method and production process of the surface layer of the part, the production and processing of each surface layer in the same production process can be combined into multiple processes.

1. The method of dividing the production and processing process flow

The parts produced and processed on CNC lathes are generally divided into standardized process flows according to centralized steps, and the methods for division are as follows:

(1) Zoning by applied CNC blades

The entire process of using the same CNC blade as a technical process can be used as a differentiation method for situations where there are many surfaces to be produced and processed for product workpieces. CNC machining centers often use these methods.

(2) Zoning by product workpiece installation frequency

The entire process of technology that can be carried out by clamping parts in one go is taken as a process flow. This type of method is applicable to parts with very little production and processing content, and all production and processing content can be carried out in one clamping process while ensuring the quality of part processing.

(3) Dividing by rough and deep processing

Make the entire process of the initial processing part of the machining process one process flow, and the entire process of the deep processing part of the machining process another process flow. This type of differentiation method is applicable to parts with hardness and strength regulations, which require heat treatment processes or parts with high precision requirements. It is necessary to reasonably remove thermal stress, and parts with large deformation after processing must be processed according to rough and deep processing stages.

(4) Zoning by production and processing location

Make the entire process of processing the same surface part as a single process flow. For parts with multiple and complex production and processing surfaces, the order of CNC lathe processing, heat treatment process, and auxiliary process flow should be scientifically arranged, and the connection problems between process flows should be well handled.

2. Standards for production and processing process flow zoning

The part is produced by several surface layers, which have their own accuracy regulations, and there are corresponding accuracy regulations in the middle of each surface layer. In order to better achieve the precision regulations of the design scheme for parts, the allocation of production and processing sequences should follow certain standards.

(1) The standard of coarsening before refining

The production and processing sequence of each surface layer is carried out in the order of initial processing, semi deep processing, deep processing, and finishing production processing, with the aim of significantly improving the accuracy and quality of the surface layer processed by the parts.

If all the surface layers of the parts are produced and processed by CNC lathes, the process flow allocation is generally carried out in the order of initial processing, semi deep processing, and deep processing, that is, after all the initial processing is completed, semi deep processing and deep processing are carried out. During the initial processing, the vast majority of the remaining amount can be quickly removed, and then each surface layer can be deeply processed in sequence, which can improve productivity and ensure the machining accuracy and surface roughness of the parts. This method is applicable to production and processing surfaces with high precision standards.

This is not certain. For example, for some production and processing surface layers with high specification precision standards, the Bending stiffness, deformation and overall dimension precision of the parts should be fully considered. It can also be considered that the production and processing surface layers should be processed in the order of initial processing, semi deep processing, and deep processing.

For production and processing surfaces with high precision standards, in the middle of the rough and deep processing process, the parts are left idle for a period of time, allowing for the complete release of ground stress on the surface of the parts after initial processing, reducing the level of ground stress deformation on the surface of the parts, which helps to improve the machining accuracy of the parts.

(2) Benchmark production and processing standards

At the beginning of production and processing, the surface that serves as the standard for deep processing has always been produced and processed. Due to the precision of the surface positioning standard, the clamping deviation is small. Therefore, the production process of all parts always starts with processing and semi deep processing towards the precise positioning reference point, and when necessary, deep processing is also required. For example, shaft parts always process and semi deep processing towards the precise positioning reference point before completing deep processing. For example, axis parts have always been CNC machined with center holes, and then produced with core hole surfaces and precision positioning holes as precision standards for machining hole systems and other surface layers. If there is more than one precision reference point, it is necessary to allocate the production processing of the reference point according to the order of standard transformation and the standards that significantly improve the machining accuracy.

(3) Face to hole standard

For components such as shells, support frames, and human bodies, the shape specifications of the plan are relatively large, and the precise positioning and reliability of the plan are reliable. Therefore, the plan should be produced and processed first, followed by the production and processing of holes. That way, not only does it provide a stable and reliable surface as a precise positioning reference point for subsequent production and processing, but it also makes it easier to produce and process holes on a neat surface, which also helps to improve the accuracy of hole processing. Generally, the process flow can be divided according to the production and processing location of the parts. Generally, the simple Solid geometry can be produced first, and the complicated Solid geometry can be produced later; First process the positions with lower accuracy, and then process the positions with higher accuracy; Mr. A produces a processing plan, and later produces processing holes.

(4) First in, then out standard

For high-precision sleeve specifications, in addition, there is a high demand for parallelism between the circle and the hole. Generally, the standard of first hole and then inner hole is selected, which is to use the outer circle as the precision positioning standard to produce and process the hole, and then use the high-precision hole as the precision positioning standard to produce and process the inner hole. This can also ensure that the inner hole and the middle of the hole have a high parallelism regulation, and the structure of the fixture used is also very simple.

(5) Standard for reducing tool change frequency

In the processing of CNC lathes, the production and processing sequence should be assigned as much as possible according to the order in which the CNC blades enter the production and processing parts.