As a type of grinding wheel, cutting discs are mainly made of ordinary abrasives bonded into a certain shape (mostly round with a through hole in the center) by a binder, and have a certain strength. Due to different manufacturing processes, the characteristics of cutting wheels vary greatly.
Five factors affecting the characteristics of cutting discs
The characteristics of the cutting wheel are determined by factors such as abrasive, particle size, hardness, structure, shape and size.
1. Abrasive
Abrasive is the main raw material for manufacturing cutting discs, which is responsible for grinding. Therefore, the abrasive must be sharp and have high hardness, good heat resistance and certain toughness.
2. Granularity
Particle size refers to the size of abrasive particles. Particle size is divided into two categories: abrasive grains and micro powders. Abrasives with a particle size greater than 40um are called abrasive grains. When grading by screening, the particle size number is expressed by the number of holes per inch on the sieve through which the abrasive grains pass.
3. Hardness
Hardness refers to the difficulty of the abrasive grains on the surface of the cut off disc to fall off under the action of grinding force. The softer the hardness of the cut off disc, the easier it is for the abrasive grains to fall off; the harder the hardness of the cutting wheel, the harder it is for the abrasive grains to fall off. The same abrasive can be made into cut off discs of different hardness, which is mainly determined by the performance and quantity of the binder and the manufacturing process.
4. Organization
Organization refers to the volume ratio of the abrasive grains, binder and pores that make up the cutting disc. It is usually graded by the percentage of the abrasive grains in the grinding wheel volume. The smaller the organization number, the greater the proportion of abrasive grains and the tighter the grinding wheel; conversely, the larger the organization number, the smaller the proportion of abrasive grains and the looser the cutting wheel.
5. Shape and size
Cutting discs can be made into various shapes and sizes. The outer diameter of the cutting wheel should be selected as large as possible to increase the peripheral speed of the cutting disc, which is beneficial to improving the grinding productivity and surface roughness. Using a wider cutting wheel can improve productivity and reduce the roughness, while avoiding burns and cracks on the workpiece surface.
