1、 It is the main technical document to guide production
The production planning and scheduling of machining workshop, the operation of workers, the processing quality inspection of parts, and the accounting of processing cost are all based on the process specification. To deal with the problems in production, the process specification is often taken as the common basis. If dealing with quality accidents, the responsibilities of relevant units and personnel shall be determined according to the process procedures. <br>
2、 It is the main basis of production preparation
When the workshop wants to produce new parts, it is necessary to first formulate the machining process specification of the parts, and then make production preparation according to the process specification. For example: the analysis and research of the key process in the new parts processing technology. Prepare the required knives, clamps and measuring tools. Purchase or manufacture of raw materials and blanks. The purchase of new equipment or the modification of old equipment must be carried out according to the process. <br>
First of all, we know that non-standard parts are relative to standard parts, so before we understand non-standard parts, we need to know what is called standard parts. Standard parts refer to the common parts, such as threaded parts, rolling bearings and so on, which have been completely standardized in structure, size, drawing, marking and other aspects and are produced by professional factories. Generalized includes standardized fasteners, connectors, transmission parts, seals, hydraulic components, pneumatic components, bearings, springs and other mechanical parts. The narrow sense only includes standardized fasteners. The commonly known standard part in China is the abbreviation of standard fastener, which is a narrow concept, but the existence of a broad concept cannot be ruled out. In addition, there are industry standard parts, such as automobile standard parts, mold standard parts, etc., which also belong to generalized standard parts. <br>
1. Benchmarking first
That is to say, the datum plane should be machined first. In the machining process, the exterior surface as the positioning datum should be machined first, so as to provide the precise datum for the subsequent process as soon as possible. <br>
2. The processing stages were divided < br > into three stages
Machining quality requirements of high appearance, are divided into processing stages, generally can be divided into rough machining, semi finishing and finishing three stages. The main purpose is to ensure the processing quality, facilitate the scientific application of equipment, facilitate the arrangement of heat treatment process, and facilitate the detection of blank defects. <br>
3. Face first and then hole < br > 2
For parts such as box, bracket and connecting rod, the plane should be machined first and then the hole should be machined. In this way, the hole can be machined by plane positioning, the position accuracy of the plane and the hole can be ensured, and the machining of the hole on the plane is convenient