Metal milling – precise machining of blanks of different levels of complexity
Among all the methods of metal processing for a long time, the leading positions are milling. Its popularity is explained by the huge number of available operations and extensive opportunities for the use of cutting tools. The principle of milling is the effect of a rotating cutter on the workpiece when they are moving with respect to each other. Milling allows you to cut flat sheets from sheet metal, create profiled profiles, dimensional details, perform various holes, grooves, cut threads.
Milling Metal Technology
Any work with the workpiece begins with the selection of a cutting tool that is suitable for a certain type of metal /alloy and the type of processing. The first stage (draft) is to give the workpiece an approximate shape. It provides for the removal of a large amount of chips and does not differ in the high quality of the surface to be treated. To bring the product to the required configuration and dimensions, which correspond to the technical specification, it is possible at the stage of finishing milling. Performing this operation requires another tool and takes more time.
Variation of processing
Depending on the fastening of the spindle and the location of the workpiece on the working surface, milling is distinguished: horizontal, vertical and at an angle.
In the direction of rotation of the cutting tool, milling can be:
- Counter, in which the blade cutter moves toward the workpiece. It is used mainly for roughing works, because this method provides low accuracy and quality of processing, but it is characterized by high productivity.
- In parallel, when the direction of feed of the workpiece and the rotation of the milling cutter coincide. In this case the processed places turn out smooth and qualitative. However, it is undesirable to carry out considerable material removal in one pass with one-pass milling, so it is most often used for finishing.
Without combined milling (counter at the initial stage and passing for final finishing), you can not do with the processing of massive parts.
Types of tools used for metal milling
The variety of mills in size and shape allows you to work with almost all types of metals: black, color, alloys of different brands. Selection of the instrument is carried out depending on:
- properties of the material being processed;
- part geometry;
- accuracy metrics.
For the treatment of metal surfaces, tools are used that have increased characteristics of wear resistance, hardness, mechanical strength, heat resistance. It can be monolithic cutters made from extremely hard steel alloys, or with tungsten carbide inserts, mineral or ceramic, diamond … They also may have differences in the number of teeth and sharpening of the cutting edges.
A variety of forms of the cutting tool makes it possible to divide the workpieces into parts, produce cuts, mill flat and three-dimensional parts, process inclined surfaces, sample grooves, grooves, holes of various shapes. Thus, the end milling cutter can handle surfaces having a large area. The shaping of the profile on the workpiece is carried out with the help of shaped cutters, the profile contour of which is selected for the required profile. End mills are used for decorating grooves, contour dents, teeth, grooves, etc.
Improvement of quality of processing with development of technologies of metal milling
The development of computer technology has made positive changes in metal processing. The use of computer simulation of processing processes led to the milling of metals to a new level. Thanks to the numerical program control, it became possible to use 3D milling, the implementation of complex terrain. At the same time, the quality, accuracy and efficiency of milling of metals has significantly increased.