1. The original data required for the formulation of CNC machining process lines
 
1. Parts design drawings, technical data, and product assembly drawings.
 
2. The production batch of parts.
 
3. Coherent technical standards required for CNC machining of parts, such as enterprise standards and process documents.
 
4. Quality standards for product acceptance.
 
5. Existing production conditions and materials. The manufacturing capacity of process equipment and special equipment, the specifications and functions of processing equipment and process equipment, and the technical level of workers.
 
2. Analysis of blank condition
 
Most part design drawings only define the shape and size of the part when it is machined, but do not specify the data of the original blank material, including the type, specification, shape, heat treatment condition and hardness of the blank. When programming, a deep understanding of the wool material is a primary start, and the application of this raw information is beneficial to CNC program planning.
 
1. Analysis of product assembly drawings and parts drawings
 
For the analysis and study of the assembly drawing, it is mainly to be familiar with the function, use and working conditions of the product, to clarify the mutual assembly position and function of the parts in the product, to understand the basis for the formulation of various technical conditions on the part drawing, and to find out its main technology The crux of the problem lays the foundation for formulating a correct processing plan. Of course, when the process analysis of ordinary parts is carried out, the analysis and study of the assembly drawing may not be carried out.
 
2. Process analysis of parts drawing
 
The analysis and study of the part drawings are mainly for the process review of the parts, such as checking the views, dimensions, and technical requirements of the design drawings for errors and omissions, especially for parts with poor structural craftsmanship. The designer communicates or proposes revisions, and the designer decides whether to make necessary revisions and perfection.
 
(1) Completeness and correctness analysis of part drawings
 
The view of the parts should meet the requirements of the national standard, the position should be accurate, and the expression should be clear; the relationship (such as tangent, intersecting, parallel) between geometric elements (points, lines, surfaces) should be accurate; the dimensioning should be complete and clear.
 
(2) Analysis of technical requests for parts
 
The technical requirements of the parts mainly include dimensional accuracy, shape accuracy, positional accuracy, surface roughness and heat treatment requirements, etc. These technical requirements should be the limit values ​​that can guarantee the performance of the parts. The analysis of the technical requirements of parts is mainly to analyze the rationality and possibility of realization of these technical requirements, focusing on the analysis of the machining accuracy and technical requirements of the main surfaces and parts, so as to prepare for the formulation of a reasonable processing plan. At the same time, through analysis to determine whether the technical requirements are too strict, because too high precision and too small surface roughness requirements will make the process more complicated, the processing difficulty will increase, and unnecessary costs will be added.
 
(3) Analysis of dimensioning methods
 
The dimensioning methods of part drawings include partial scattered labeling method, centralized labeling method and coordinate labeling method. For parts processed on CNC machine tools, the dimensions on the part drawing should be marked as concentrated or marked with the same datum (that is, marked with coordinate dimensions) as far as possible under the condition that the function can be guaranteed, which is convenient for the preparation of CNC programs. , and is beneficial to the unification of design benchmarks, process benchmarks and programming origins.
 
(4) Analysis of parts material
 
Under the condition that the function of the parts is satisfied, cheap materials should be selected, and materials should be selected based on the domestic market, and precious and scarce materials should not be easily selected.
 
(5) Structural manufacturability analysis of parts
 
The structural manufacturability of the parts refers to the feasibility and economy of the designed parts to be manufactured under the conditions that can meet the performance requirements of the use. Good structural manufacturability will make parts easy to process, save costs and materials; while poor structural manufacturability will make processing difficult, increase costs, waste materials, and even fail to process. Through the process of analyzing the structural characteristics, accuracy requirements and complexity of the part, the processing method required for the part and the type and specification of the CNC machine tool can be determined.