Grinding is what? Process technology

Sanding is one of the most common operations, based on the principles of abrasive processing. The removal of a rough surface on fragile and hard substrates is required in various areas, including the organization of floor coverings in construction or the bringing of production structures to a state that meets the standards. In the traditional sense, grinding is the elimination of the outer layer of the surface in order to give it a more aesthetic appearance. In addition, this operation is associated with sweeping and leveling, which is also quite fair.

The technology of the operation

All methods of grinding in one form or another assume the use of abrasive. It is a material whose structure is represented by grains of fine sand or rock particles that are prominent from the main grain surface. During the grinding process, the rough surface acts on the target area, thereby relieving it of unevenness and contamination. In general, the grinding process can be represented as a mechanical action on the work area due to abrasive, resulting in the surface acquiring new qualities. This can be cleaning the material, leveling its surface or eliminating the whole layer. In its simplest form, grinding is represented by the function of sandpaper, which can be used to smooth the edges of a wood block. In this case, the technology is implemented manually, but there are mechanized machines and devices that automatically provide the effect of abrasive action.

Differences from polishing

On some parameters of the working operation, grinding and polishing intersect, but the principal tasks for them are slightly different. The fact is that polishing is realized with the aim of obtaining a decorative effect. This is what determines the peculiarity of the technical organization of the process. Polishing measures suggest a more accurate and gentle impact on the material. In this case, a high degree of rigidity can be maintained in the processing of metal or stone, which allows deforming the outer layers at the depth of the microns. Another thing is that we are talking about a minimal invasion of the surface structure, which often excludes even damage to the protective layer. In turn, grinding is often a rough removal of the upper layer, which is provided by abrasives of a coarse fraction. Another difference is the use of special abrasive pastes and mastics in the polishing process. They help to more effectively realize the mechanical effect on the structure of the material, preventing the risk of excessive damage to the workpiece.

Varieties of grinding

There are several classifications, according to which grinding technologies are distinguished. First of all, this division concerns manual and machine operations. The same treatment with sandpaper or stone abrasive bars refers to manual methods. Machine impact on the surface is more productive and efficient. In this group of methods, tape, disc and flat grinding methods are distinguished, which differ in the characteristics of the working tooling and in the way in which the force action is organized. For example, tape machines operate at the expense of an electric motor, and the functional equipment is represented by belts, on the surface of which there are abrasive particles. Disc and flat abrasive elements are also integrated into the tooling of machines with electric drive and independently carry out surface modification. From the user it is only necessary to set the parameters of the abrasive action in advance and to direct the unit during operation.

Features of centreless grinding

Traditionally, the organization of grinding involves a central fixation of the workpiece without the possibility of changing its position. But there is also a method of centerless machining, in which the article is given a spin. This approach justifies itself in cases where it is necessary to perform the processing of metal parts with high accuracy. As a matter of fact, grinding is a technology of dynamic abrasive decoration of workpiece surfaces. Typically, several circles are used to implement this method, fixed on the functional tooling of the machine. Of course, centerless processing is applicable only in conditions of a full-fledged production process, where operators have the opportunity to provide not only a reliable position of the workpiece, but also to give it a spin.

Tools for grinding

The grinding tool includes manual devices in the form of files and abrasive stones, and mechanized equipment. The segment of mechanized means deserves the greatest attention. They differ in design, method of influence and scope. In the construction industry, for example, floor machines are common, thanks to which wooden surfaces are treated. This technique provides for different grinding modes, each of which sets a special set of operating parameters. In particular, the intensity of the abrasive action, the depth of cut and the speed of movement of the working tool can be adjusted. Simpler devices of manual type, but with electrical stuffing, are more often used for processing individual structures and parts. Such grinding machines find their place in workshops and at certain stages of production cycles where automation of the technological process is impossible.

Materials for grinding

Virtually all grinding operations, regardless of the tool used, involve the use of abrasive. This is a single piece or surface, which is characterized by roughness and granularity. In practice, this element can represent both a grinding head in the machine, and a separate homogeneous bar that projects both the handle and the machining surface simultaneously. In this case, there are materials of natural and artificial origin, which should be considered separately.

Natural and synthetic abrasives

Today, the characteristics of diamond abrasives that are of natural origin are highly valued. The crumb of this mineral is used in manufacturing processing circles of varying degrees of hardness. With the help of such equipment, grinding of metal and stone is realized. Also a segment of natural abrasives is pumice, garnet, quartz and corundum.

Artificial or synthetic abrasive materials also do not work without the use of natural particles in the structure, but they are subjected to multi-stage processing. To date, grinding technology of this type involves the use of various alloys, blends and mineral slag. Often, in order to save the production process, technologists include in the blend of abrasives and certain types of industrial waste.

Finishing Grinding

If the treatment is performed to achieve a certain aesthetic effect, then after the basic cleaning and alignment, a finishing step may be required. Its task is to provide the surface with optimal roughness indices. Again, unlike polishing, grinding is the way to get a smooth and even surface with a tolerance of haze. Finishing of this type is realized by surfaces, the abrasive of which is designed for an average depth removal of 0.15-0.02 μm. And this task can be performed by universal grinding machines, the capabilities of which also allow coping with rough cleaning. Again, for different operations, the appropriate modes of operation of the equipment are applied.

Conclusion

Grinding operations are used in various areas, but equipment developers focus on the surface finishing function. This can be a classic parquet, and wall materials in the form of plaster, as well as metal and plastic decking. Of course, the grinding of the surface of a single part is included in the range of production operations. The technology for performing this type of work is more precise and flexible in management. Manual labor in this area is practically not involved, and in the first place machines with programmable control and control are increasingly coming out.