Before you start programming, you must analyze the design drawings and technical requirements in detail to get the best machining solution.
First, the original data required for the development of CNC machining process lines
1. Parts design drawings, technical materials, and assembly drawings of the products.
2, the production 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 prerequisites 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.
Second, the analysis of the condition of the blank
Most part design drawings only define the shape and size of the part when it is machined, and do not specify the data of the original blank material, including the type, size, shape, heat treatment and hardness of the wool. When programming, a deep understanding of wool is a prime start, and applying this raw information is beneficial to the NC program.
1. Assembly drawing and part drawing analysis of the product
For the analysis and research of assembly drawings, it is mainly to know the function, use and working premise of the products, to clarify the position and function of the parts in the product, to understand the basis of the technical premise on the parts drawing, and to find out the main technology. The crux of the problem lays the foundation for the development of the correct processing plan. Although ordinary parts are subjected to process analysis, analysis of assembly drawings may not be performed.
2, the process analysis of the parts drawing
The analysis and drilling of the parts drawing is mainly for the process review of the parts, such as checking the view of the design drawings, dimensioning, technical requirements, whether there are faults or omissions, especially for parts with poor structural craftsmanship, if possible The designer communicates or proposes changes, and the designer decides whether to make the necessary modifications and perfection.
(1) Completeness and correctness analysis of part drawing
The view of the part should conform to the request of the national standard, the position is accurate and the expression is clear; the relationship between the geometric elements (point, line, surface) should be accurate (such as tangency, intersection, parallel); the dimension should be complete and clear.
(2) Analysis of parts technology request
The technical requirements of the parts mainly include dimensional accuracy, shape accuracy, positional accuracy, surface roughness and heat treatment request. These technical requests should be the limit values that can guarantee the functional conditions of the parts. The analysis of parts technology requests is mainly to analyze the fairness and realization possibilities of these technical requests, focus on the processing accuracy and technical requirements of the primary surface and parts, and prepare for the formulation of a fair processing plan. At the same time, through analysis, it is too strict to affirm the technical request. Due to too high precision and too small surface roughness request, the process will become complicated and the processing difficulty will increase, adding unnecessary capital.
(3) Dimensioning method
The dimensioning method of the part drawing has a partial dispersion labeling method, a centralized labeling method, and a coordinate labeling method. For parts machined on CNC machine tools, the dimensions on the part drawing should be as large as possible or marked with the same reference (ie, coordinate coordinate size) under the condition that the function can be guaranteed, which facilitates the NC programming. It is also beneficial to the unification of design benchmarks, process benchmarks and programming origins.
(4) Analysis of parts and materials
Under the conditions of satisfying the function of the parts, cheap materials should be used. When selecting materials, they should be based on domestic products, and do not choose expensive and scarce materials.
(5) Structural process analysis of parts
The structural manufacturability of a part refers to the feasibility and economy of the designed part, which can be manufactured under the conditions that can satisfy the request of the function. Good structural processability will make parts easy to process, save cost and save materials; and poor structural manufacturability will make processing problems, increase costs, squander materials, and even impossible processing. Through the process of analyzing the structural features, precision requirements and complexity of the parts, it is possible to affirm the machining methods required for the parts and the types and specifications of the CNC machine tools.