Grinding and polishing The manufacturer tells you how the polishing machine works and its characteristics:
The polishing wheel is generally made of materials such as felt, rubber, leather, cotton or pressed cardboard, and is a flexible wheel with a certain elasticity. The polishing paste is prepared from abrasives such as chrome oxide, iron oxide, etc., and oleic acid and soft fat.
Generally used abrasives are electric steel jade, yttrium oxide, mainly used for processing steel; silicon carbide, chromium oxide Mainly used for processing aluminum, hard aluminum and copper. Silicon carbide and iron oxide are mainly used to process cast iron parts.
When polishing, the part is pressed against the high-speed rotating polishing wheel, and the metal surface is produced by the polishing paste medium. A very thin layer of soft film that can be removed with a softer abrasive than the part material without leaving scratches on the part surface. In addition to the high-speed friction, the surface of the part is exposed to high temperature, and the surface material is squeezed to plastically flow, so as to fill the original microscopic unevenness of the surface, and obtain a very bright surface, such as a mirror surface.
One of the important conditions of a mechanical polishing machine is that it must have an axial reciprocating vibration with a very high frequency and a small stroke to be polished. On the device of the wheel, in order to constantly intersect the wear marks, thereby eliminating the marks formed on the machined surface. This movement is usually achieved by a special mechanism mounted on the main sleeve of the mechanical polishing machine, that is, a vibrator. When using a jig for mechanical polishing, an elastic gasket or spring device made of leather, rubber or the like should be placed at the workpiece.
Polishing features and applications
Polishing has the following characteristics:
1. Polishing The method is simple and the cost is low. The polishing generally does not require complicated and special equipment, and the processing method is simple and the cost is low.
2. Polishing the surface of the surface, because the elastic polishing wheel is pressed against the surface of the part, it can change with the surface of the part. That is, it is consistent with the melody, and it is easy to realize the surface polishing, which is convenient for finishing the mold cavity.
3. Polishing does not improve processing accuracy. Since there is no rigid motion connection between the polishing wheel and the part, the polishing wheel is elastic, so it cannot guarantee that the material is evenly removed from the surface of the part, but only the surface roughness value can be reduced, and the processing precision cannot be improved. Therefore, polishing only It is limited to the surface decoration of some products, or as a pre-processing before plating.
4. Polishing labor conditions are poor. Polishing is now mostly manual, heavy work and poor working conditions.
The effects of grinding, honing, super-lighting and polishing are different, polishing only improves the surface of the part The degree of lightness is not beneficial to the improvement of the roughness of the part. Super-light grinding can only reduce the surface roughness of the parts, but can not improve the size and shape accuracy. Grinding and honing can not only reduce the surface roughness of the parts, but also improve the size and shape accuracy to some extent.