Machining of metal: types and methods. Machining of metal

Unlike other types of processing metal machining does not affect the internal structure of the metal or alloy, but only changes its size and configuration. The essence of machining is the fitting of a hardened part to the required dimensions specified in the drawing. For mechanical processing of metal, cutting tools, metal-cutting machines and welding are used.
The parts obtained after such processing have an ideal shape, exact dimensions and a flat surface, strictly corresponding to the drawing. By the way, finished metal parts that have undergone mechanical processing can be viewed at the Metalloobrabotka international exhibition, which will be held at the Expocentre Fairgrounds. They will also demonstrate the equipment itself, with the help of which it is possible to carry out mechanical processing, including new modernized metal-cutting machines.

How is the sizing done?

Mechanical restoration metal can be carried out using various metal-cutting tools and, depending on it, several types of mechanical impact on the part can be distinguished:

  • Machining;

  • Processing with plastic deformation;

  • Processing using the deforming cutting method;

  • Electrical processing.

Metal cutting

Cutting is most often used to obtain machine parts. The essence of this method is that after cutting a new metal surface is obtained. This is due to the deformation of the surface layer of the part with the help of metal-cutting machines and tools and the subsequent removal of these layers. This process is accompanied by the appearance of shavings of the upper layer of metal. Chips, that is, the residual material after processing, is called the allowance. In other words, it is redundant material. Its size should be minimal to reduce labor intensity and processing costs, but sufficient to obtain a high-quality part with the required set of properties.

Depending on the tool used for metal machining, there are several types of cutting:

  • turning;

  • Milling;

  • drilling;

  • Planing;

  • chiselling;

  • grinding;

  • Stretching.

There are many more auxiliary types of cutting, they are used depending on the external indicators of the part itself - for processing the outer and inner cylindrical surfaces or planes.

Metal processing by plastic deformation and electrophysical processing

Plastic deformation of metal is used to change the shape, configuration, dimensions and physical and mechanical properties of the prepared part. This includes forging, pressing, stamping, thread rolling.

Electrophysical processing is characterized by the use of various phenomena of electric current:

  • EDM;

  • Electrochemical processing;

  • Electric arc welding.

To achieve the most productive result of metal processing in production, a wide range of machining tools is used, the most common types of equipment include:

  • Lathes;

  • Drilling and boring machines;

  • grinding machines;

  • Milling and broaching machines;

  • Press.

Quite often, metal after 100-ton pressing or forging is treated by an electrochemical method - various coatings are applied. For example, metal can be brass-plated, nickel-plated, tin-plated, and so on.

Metrological studies and measurements help to determine the minimum material costs, the lowest allowances and the conditions necessary for high-quality machining of metal.

Depending on the type of machining chosen, it is possible to obtain a mass of parts with different levels of surface roughness and coating, size and holes. With such a wide range of machining tools in production, small parts (nuts, threaded screws, common household parts such as doorknobs) and larger machine parts - engines, construction equipment and more complex mechanisms - are obtained.

Such a seemingly simple metalworking contains many nuances, missing one of which, it will be impossible to achieve the desired result.

Most machine parts are made by machining. The blanks of such parts are rolled products, castings, forgings, stampings, etc.

The process of machining parts by cutting is based on the formation of new surfaces by deformation and subsequent separation of the surface layers of the material with the formation of chips. The part of the metal that is removed during processing is called the allowance. Or, in other words, the allowance is an excess (in excess of the drawing size) layer of the workpiece left for removal by a cutting tool during cutting operations.

After removing the allowance on metal-cutting machines, the workpiece acquires the shape and dimensions corresponding to the working drawing of the part. To reduce the labor intensity and cost of manufacturing the part, as well as for the sake of saving metal, the size of the allowance should be minimal, but at the same time sufficient to obtain a good quality part and with the necessary surface roughness.

In modern mechanical engineering, there is a tendency to reduce the volume of metal cutting by increasing the accuracy of the original workpieces.

Basic methods of metal cutting. Depending on the nature of the work performed and the type of cutting tool, the following metal cutting methods are distinguished: turning, milling, drilling, countersinking, slotting, broaching, reaming, etc. (Fig. 12).

Turning- the operation of processing bodies of revolution, helical and spiral surfaces by cutting with cutters on machines of the turning group. When turning (Fig. 12.1), the workpiece is given a rotational movement (main movement), and the cutting tool (cutter) is given a slow translational movement in the longitudinal or transverse direction (feed movement).

Milling- a high-performance and widespread process of processing materials by cutting, performed on milling machines. The cutter receives the main (rotational) movement, and the workpiece receives the feed movement in the longitudinal direction (Fig. 12.2).

drilling- the operation of processing the material by cutting to obtain a hole. The cutting tool is a drill that performs a rotational movement (main movement) of cutting and an axial movement of the feed. Drilling is carried out on drilling machines (Fig. 12.3).

Planing- a method of machining planes or ruled surfaces. The main movement (rectilinear reciprocating) is performed by a curved planer, and the feed movement (rectilinear, perpendicular to the main movement, intermittent) is the workpiece. Planing is carried out on planing machines (Fig. 12.4).

chiselling- a method of processing planes or shaped surfaces with a cutter. The main movement (rectilinear reciprocating) is performed by the cutter, and the feed movement (rectilinear, perpendicular to the main movement, intermittent) is performed by the workpiece. Slotting is carried out on slotting machines (Fig. 12.5).

grinding- the process of finishing and finishing of machine parts and tools by removing a thin layer of metal from their surface with grinding wheels, on the surface of which abrasive grains are located.

Rice. 12

The main movement is rotational, which is carried out by a grinding wheel. With circular grinding (Fig. 12.6), the workpiece rotates at the same time. With flat grinding, the longitudinal feed is usually carried out by a workpiece, and the transverse feed is carried out by a grinding wheel or a workpiece (Fig. 12.7).

Stretching- a process, the productivity of which is several times greater than that of planing and even milling. The main movement is rectilinear and less often rotational (Fig. 12.8).

In many areas of industry, a process such as mechanical processing of metals is indispensable. Machines, machine tools and tools are constantly being improved, operations are carried out faster and faster from year to year. On the manufacturing enterprises work machines specialized and general purpose. With the help of such machines, it is easy to cut blanks of sheet, profile or other types. Methods for separating the material are also widely used: with a cutter, a band saw, and others.

Technological processes of mechanical processing of metals

Machining of metals is a rather complex process, which results in parts of certain sizes and given shapes. There are two ways of mechanical action on the material. The first method is expressed in the removal of the top layer from the working surface. In this case, the depth can be different depending on the requirements for the dimensions of the part. In the second method, the material is not damaged in any way during the initial impact, it can only be pressed, stamped, forged, rolled. As a rule, this method of influence is followed by the stage of further work on the part.

The complex of technological operations for giving a certain size and shape to parts provides for various types of mechanical processing of metals. The main ones are turning, milling, planing, grinding and drilling. Now all operations are carried out on modern multifunctional machines. So, the same machine can perform successively different functions. To do this, you just need to install the programs correctly and apply them in time. the right tools. Many names of tools speak of their purpose: a drill for drilling, a milling cutter for milling, and so on.


All types of mechanical processing of metals are diverse, they have their own differences and nuances. The most modern way that meets high-tech requirements is processing on lathe. They are automatic, semi-automatic and CNC. As a rule, milling is used to process shaped or flat surfaces. different types: end, end or shaped.

Now many modern industries offer metal machining services. There are also a lot of machines for carrying out these works, but time dictates its own conditions, so the machines are constantly being improved. So, primitive machines have almost everywhere been replaced by automatic lines. Dynamically developing enterprises are trying to expand production as much as possible with the help of high-tech equipment. Thus, with a high degree of probability it is possible to guarantee high quality products and minimum order processing times. Any production wins if it prioritizes a good production of quality products, regardless of the volume of the order and its complexity.

Equipment for mechanical processing of metals

As a rule, metal machining services are performed quickly and in full compliance with all standards when qualified personnel take over the work. In addition, each promising enterprise provides for work optimal conditions: sufficient availability of production space, necessary equipment. It should be noted that in order to successfully and quickly complete the order, the staff needs to provide machine tools, welding and technological equipment.


So, to perform the work, you should choose the right equipment for the mechanical processing of metals. Of course, for the main work - chip removal, the turning and milling direction is responsible. The most common equipment in this area is CNC turning centers and centers. Modern models make it possible to manufacture parts that meet the highest requirements regarding the geometric parameters of the product and the roughness of its surface. The advantages of new models of machines are: accuracy, speed, improved parameters of working areas.

The equipment for mechanical processing of metals is currently presented in a wide range. Among the variety of models, there are both the most popular and quite rare (relatively frequent applications). For example, a carousel machine that can process a part with a diameter of up to nine meters. Such a machine is not used often and not everywhere. Quite in demand are jig boring machines that provide high-quality boring at any angle and boring machines with rotary tables. Each enterprise, whose field of activity is metal machining, tries to have milling, gear-hobbing, radial, horizontal and vertical drilling machines available.

NZMK Group produces metal products, metal products, and provides services such as machining of metal parts.

Metal machining services. Plant Capabilities

Machining does not directly or indirectly affect the change in the internal structure of the material, providing only a change in its configuration and geometric dimensions.

Customers have the option of placing processing orders with us through:

  • cutting workpiece;
  • Plastic deformation:
    • o Forging;
    • o Stamping;
    • o Pressing;
    • o Thread rolling;
  • Deformation cutting;
  • Electrophysical processing:
    • o Electroerosive;
    • o Electrochemical;
    • o Electric welding (arc);
  • Electrical processing.

Machining of metal cutting is most often in demand. At the Novomoskovsk Steel Structures Plant, cutting is performed by the following types:

  • Turning - is performed in cases where the workpiece almost matches the size of the desired part. Required by the customer metal machining performed on machines for various purposes:
    • o Turning;
    • o Broaching and milling;
    • o Drilling and boring, etc.
  • drilling;
  • chiselling;
  • Stretching;
  • Milling - carried out on special machines;
  • Planing - is performed on machines and transverse planing equipment;
  • Grinding - performed on grinders

Metal machining services are provided using a number of auxiliary types of said processing.

Stages of machining of metal parts according to customer drawings

Having received a set of working documentation from the customer, NZMK Group of Companies technologists determine:

  • whether it is possible to manufacture parts corresponding to the TOR on the existing equipment;
  • what machines are required for this;
  • what modes should be processed, etc.

Quite often, after that, a decision is made to machine the workpiece by cutting. During this operation, the excess metal layer (allowance) is removed. After that, the part corresponds to the dimensions specified by the customer's drawing.

The decision to turn the workpiece is made in those cases when, in terms of its geometric characteristics, it differs slightly from those that the finished part should have.

Mechanical restoration drilling allows you to make the necessary holes in the structure. And chiselling or milling is to give the product the required geometric parameters.

In some cases, blanks are processed by pressure. For example, mechanical processing of metals(non-ferrous) often involves the use of hot forging. In this case, forging can be performed by one of the following options:

  • free;
  • using a blacksmith's stamp.

An alternative processing option can be pressing technology. There are several presses of various capacities and purposes at the Novomoskovsk Steel Structures Plant.

Similar posts