Machining of metal parts

The production of a part is a time-consuming process, involving a huge number of different types of processing. As a rule, it begins with the compilation of route technology and the execution of the drawing. This documentation contains all the necessary data for the manufacture of the part. Machining is quite an important stage, including a huge number of different operations. Let us consider them in more detail.

Material

Depending on the required part, the metal material is also selected. Upon its subsequent processing, the finished product is obtained. In other words, metal material is a workpiece. It can be of several types: stamping, forging, rolling, cermet. Each type of blank is different in the way it is made. If forging is used, for example, forging hammers are used in small-scale production, then metal powders are pressed in molds at a pressure of 100-600 MPa to produce a metal-ceramic material.

Processing of flat and cylindrical surfaces

Flat surfaces are processed by milling, planing, pulling. Typically, such blanks include sheet metal and cermets.

Planing is carried out on cross-machine and planing machines. When machining on the first, the main movement is performed by the cutter, and the feed motion is performed by the machine table. On the planing machine - the opposite is true. In addition, such machining is considered to be unproductive, because it has too low cutting speed. The working tool loses a lot of time to reverse idling. Advantages of such processing are the provision of straightness and direct proportionality.

Milling

One of the most highly productive methods of processing both flat and cylindrical surfaces is milling. This is due to the fact that it is carried out simultaneously by several teeth of the mill. The machining can be carried out in a sequential, parallel, sequential-parallel and continuous manner. The surfaces with roughness Rz = 0.8-0.63 μm can be processed by milling and this treatment will be called thin.

Stretching

In this way, the parts are processed in mass and large-scale production. In some cases, pulling can be replaced by grinding and chiselling. This machining has very high accuracy. Stretching can be done both in the vertical direction and in the horizontal direction. This processing is used for operations involving increased accuracy, and the cutting tool operates under conditions of enormous loads such as compression, bending, stretching.

For example, stretching is used when processing holes in firearms, for cutting keyways and splines. Broaches are used as a cutting tool, both solid and prefabricated. They are made of high-speed and medium-alloy tool steels.

Machining of holes and threads

Mechanical machining of parts can not do without such important tools as drills, countersinks, taps, sweeps. In order to drill a hole of the required diameter, calculation of the cutting regime for this process is mandatory. As a rule, the hole is drilled to the required diameter, taking into account the allowance for subsequent processing. In order to ensure the best accuracy, a reamer is used, and a countersink can be used for semi-finished processing.

Mechanical machining of parts can also be performed with a tap. This tool is designed for threading in existing holes. There are taps for blind and through holes. To cut the external thread using cutters and dies. Before using them, it is necessary to slightly protrude the workpiece. In order to create a high-quality and efficient approach to the cutting tool, a chamfer at the end of the product is removed before the operation begins. It should have the same height as the thread profile.

In the rare case, the machining of metal parts and threading is performed using screw heads. They are fastened in the shank by a shank. It can have prismatic, radial or round combs. They do not contact the threaded thread in the reverse stroke, because at the end of the process they disperse in the automatic mode.

Mechanical processing of metal on machines and lines is studied in many colleges and universities. The specialty has the code 36-01-54 and is subdivided into such directions: the milling machine, the turner, the grinder, the controller of locksmith and machine works, the operator of automatic (AL) and semi-automatic lines. As modern technologies do not stand still, it is very important to study the mechanical treatment of metals on CNC machines and on AL.

Such equipment greatly facilitates the work of operators. Their main task is to control, adjust and load-unload parts and blanks. All operations of automatic lines are carried out with the help of special computer programs and practically do not require the intervention of operators. The use of AL makes it possible to significantly reduce the cost of processing and the time of manufacturing the parts.