xiehe model

1. About the machining process of parts

The main content of the machining process of parts In modern society, the machining of parts is generally processed by numerical control. Therefore, when machining parts, it is necessary to understand the relevant processing technology, formulate suitable machining plans, and process the parts. In-depth discussion and analysis of CNC machining technology. First of all, when CNC machining of parts, it is necessary to choose a suitable CNC machine tool, work on the CNC machine tool, and determine what the processing process is.

Then formulate a suitable machining plan for CNC machining of parts, analyze the drawings of the parts to be machined, analyze the content of the parts and adopt suitable machining techniques. In the machining of parts, the most important thing is to design the process of machining the parts, which is related to the quality of the parts. We need to distinguish the steps of the machining procedure of the parts, the selection of benchmarks, the selection of processing tools, the selection of fixtures, and the installation and processing. Affirmation of strategy and process parameters to formulate the most suitable processing technology. In addition, we need to compile and inspect the CNC programming program for parts machining, control programming errors, and improve programming quality and efficiency.

The characteristics of the machining process of parts The machining of parts is generally carried out by numerical control, so it is inevitable to have the characteristics of numerical control machining, and also has its own characteristics.

(1) CNC machining of parts requires the content of the processing technology to be meticulous. When CNC machining the parts, the CNC machining plan will be formulated in advance, and then operated on the CNC machine tool, including the machining program, the selected tool, the machining method and the corresponding machining parameters, etc. These require the machining of the parts. It is necessary to have a detailed and meticulous plan, analyze the plan, and finally constitute the machining program of the part.

(2) The mechanical CNC machining process of parts is required to be strict and precise. The machining process of the parts is in the form of CNC machining, which makes the machining of the parts more precise and quality, and does not require too many people during the machining process, saving manpower, but on the other hand, the reduction of human intervention , so that the parts cannot be artificially adjusted if there is a problem in the processing process, so the mechanical numerical control processing technology of the parts is set relatively closely and accurately on the level, and there can be no small errors, because the existence of errors is likely to cause machining The process does not meet the specifications and the parts are discarded, resulting in mechanical accidents.

(3) When performing mechanical numerical control processing on parts, mathematical calculations should be performed on the graphics of the parts and the set values of the programmed dimensions. Since the machining of parts is in the form of numerical control, programming and design must be carried out before machining, the geometric form of the size of the part, and the mathematical calculation of the size of the part to be machined, so it is necessary to comprehensively consider all aspects when programming. to optimize the design of the part.

2. Analysis of the principles of machining process design of parts

The principle of positioning datum selection The positioning datum refers to the appearance of the relative position of the part to the machine tool and the tool when the part is machined. It is the rough datum. If the positioning datum that has been processed is used after the original processing, this is the fine datum. Then when machining parts, what kind of appearance should be selected as the positioning reference, which needs to be cautious when machining parts. What kind of positioning datum is selected will affect the quality of parts processing and the complexity of the structure of the machine tool fixture. So what are the principles for choosing rough benchmarks and fine benchmarks?

The principle to follow when selecting the rough datum When selecting the rough datum to process the part, it is necessary to ensure that the material is sufficient, the machining surface has sufficient allowance, and the size and position of the machined surface on the unmachined side of the part must conform to the processing drawings requirements. If a rough datum is selected, it is necessary to ensure that the surface of the part is easy to locate, easy to clamp and process, and the selected fixture should be as simple as possible.

When choosing the rough datum, be sure to determine the machined surface and the unmachined surface, and have an accurate position selection. Generally, the unmachined surface is used as the rough datum. When selecting the rough datum, it is generally to satisfy the important appearance that the roughing allowance is small and average. When selecting the unmachined surface, the position error of the rough datum can be evenly distributed on the unmachined surface, and the rough datum surface is as large as possible. It may be flat and intact, without gaps, which is conducive to setting the position.

When selecting the fine datum according to the principle of selecting the fine datum, first check whether the fine datum surface can be easily positioned and clamped, and if a certain surface is selected as the fine datum, the selected surface can be uniformly used when selecting other surfaces. The positioning method is used to improve the processing efficiency, so be careful when positioning the precise surface. The fine datum adopts the principle of precise coincidence, that is, the positioning and finishing of other surfaces are carried out with a unified positioning principle.

The principle of selecting the surface processing method of parts For different parts surface and different parts processing requirements, parts structure characteristics, material properties, etc., it is necessary to choose the corresponding processing method to process the parts surface. When confirming the part processing method, first confirm the final processing method of the part, and then from the back to the front, deduce and confirm the processing method of the previous process.

(1) The principle of economic applicability

When processing parts, first analyze the processing economy of the processing method, that is, select and analyze the equipment, technology, skilled workers, and processing time, that is, to determine the applicability of processing, the accuracy range of processing, and the accuracy range. It should be adapted to the accuracy requirements and surface roughness requirements of the surface processing of the parts, so as to ensure that the processed parts meet the requirements.

(2) The principle of adaptation of production types

Different types of production to choose different processing methods, mass production, often use high-efficiency machine tools and advanced processing methods, and on the small batch production of parts, the general use of ordinary machine tools and conventional processing methods.

(3) The principle of matching of processing methods

The machining method selected for machining the parts should match the shape accuracy and position accuracy of the machined surface, be compatible with the parts data, and be compatible with the existing equipment conditions and the technical level of workers. The problem should be analyzed in detail, and the processing should be carried out according to the processing requirements and existing materials, and do not blindly match, resulting in processing failure.