The production process and technology of the mechanical processing process

Is the production process from raw materials, Or semi-finished products) All the process made products. For machines including transportation and storage of raw materials, production preparation, blank manufacturing, parts machining and heat treatment, product assembly and debugging, paint and packaging, etc. Modern enterprise with the content of the production process is very extensive, the principle and method of system engineering organization and guide the production, the production process as a production systems with input and output. Can make the enterprise scientific management, make the enterprise more resilience and competitiveness. In the process of production, directly change the raw materials ( Or blank) Shape, size and performance, and make it into a finished product, the process of the called process. It is the main part of the production process. For example, the blank casting, forging and welding; Change the material performance of heat treatment; Parts of machinery processing, etc. , all belong to the technological process. The technological process is composed of one or several of order process. Process is the basic component of unit process. Process refers to the work in a place, to one or a set piece for completion of that part of the process. Constitute the main characteristics of a process is not changing processing objects, equipment and operator, and the content of the process is completed in a row. The process can be divided into the following two processes: step 1: cylindrical, surfacing on lathes, boring and inner hole chamfer; Step 2: six drill holes on the drilling machine. In the same process, the workpiece is likely to be installed after a couple of times. In a clamping workpiece has done that part of the process, known as the installation. In step 1, there are two installation. Installation: for the first time in three jaw chuck clamp cylindrical, surfacing C, boring and inner hole, inner hole chamfer, outside circle. The second installation: switching with three jaw plate clamped cylindrical, and facing A and B, inner hole chamfer. Second, the production type production type is usually divided into three categories. Single production make a single parts, rarely repeated production. Batch production in batch production of manufacturing the same parts. Mass production when the production quantity is very big, most of the work place is often repeated for the production of a part of a process. For parts of the process, due to the different parts of the production, and adopted by the method, machine tool equipment, measuring tool, blank and technical requirements of workers, etc. , have very big difference. Three, the machining allowance in order to work out qualified parts, must be cut off from the blank that the thickness of the metal layer, called the machining allowance. Machining allowance and allowance can be divided into the process and the total allowance. A process for removal of the layer thickness of metal, known as the process of machining allowance. From the blank to the finished product, it will be altogether resection margin, is called the total surplus, is equal to the corresponding surface allowance of each process. On the workpiece for machining allowance is for the purpose of removal procedure to stay on the processing error and surface defects, such as chilled casting surface layer, porosity, sand inclusion, the oxide coating on the surface of the forging, the decarburization layer, surface crack, surface roughness and machining of internal stress after layer, etc. To improve the precision of the workpiece and the surface roughness. The size of the machining allowance have significant influence on the processing quality and production efficiency. Machining allowance is too big, not only increased machining the amount of labor, reduces the productivity, and increased the materials, tools, and power consumption, improve the processing cost. If machining allowance is too small, it can not eliminate all the defects and working procedure in the error, and clamping can't compensate the machining error, cause waste. Its selection principle is on the premise of guarantee quality, make allowance for as little as possible. Generally speaking, the more refined, the smaller process allowance. Four, the benchmark is made up of several surface mechanical parts, studies the relative relations on the surface of the parts, must determine a benchmark, the benchmark is used to determine other parts of dot, line, the position is based on dot, line, face. According to the different function of the benchmark, the benchmark can be divided into two categories, design datum and technology datum. Design base on the part drawing is used to locate other dot, line, face the benchmark, known as design basis. Shaft sleeve parts, the outer circle and inner hole design datum is part of axis, the design of the end face is B, C datum, the axis of the bore is the benchmark external circular radial runout. Process benchmarking parts used in the process of processing and assembling of benchmark, known as benchmark process. Process benchmarking is divided into different according to the use assembly datum, measurement datum and position datum. ( 1) Assembly benchmark to determine when the assembly parts in parts or products in the position of the benchmark, known as assembly benchmark. ( 2) Measurement benchmark to test finished surface size and position of the benchmark, referred to as the measuring datum. Axis, the inner hole is cylindrical radial runout measurement benchmark; ( 3) When locating datum processing workpiece positioning the benchmark, known as locating datum. As the surface of the locating datum ( Or line and point) , only the first step in choosing raw surface of the blank, the positioning surface of said crude benchmark. In each working procedure has been machined surface can be adopted as a locating datum, the positioning surface of the said fine benchmark.