Basic Knowledge of Grinding
What is grinding?
Grinding is a mechanical processing method that removes material. In a narrow sense, it refers to the processing method of removing excess material on the workpiece with an abrasive tool. Grinding wheels, superabrasive tools, grinding heads, mounted points, sand tiles, oilstones, abrasive belts, etc.
In a broad sense, it refers to the processing method of using abrasives and abrasive tools to remove excess material on the workpiece. Including grinding in a narrow sense, as well as grinding and polishing.
Grinding is a processing method that removes the excess layer on the surface of the workpiece by means of the cutting action of the abrasive tools so that the surface quality of the workpiece meets the predetermined requirements. Grinding is one of the more widely used material removal methods.
Grinding principle
The grinding of the surface of the workpiece using high-speed rotating grinding wheels and other abrasive tools. Grinding is used to process internal and external cylindrical, surface, centerless, profile, conical and flat surfaces of various workpieces, as well as special and complex forming surfaces such as threads, gears and splines. Due to the high hardness of the abrasive grains, the abrasives have self-sharpening properties. Grinding can be used to process various materials, including tungsten carbide, high speed steel, hardened steel, alloy steel, cermet, glass, ceramics, marble, quartz, silicon wafer and other high-hardness metals and non-metallic materials. metallic material. Grinding speed refers to the linear speed of the grinding wheel, which is generally 30 to 35 m/s. When it exceeds 45 m/s, it is called high-speed grinding.
Grinding is usually used for rough grinding, semi-finishing and finishing, and the accuracy can reach IT8~5 or even higher. The surface roughness is generally Ra1.25~0.16 microns for grinding, and Ra0.16~0.04 microns for precision grinding, ultra-precision grinding Cut to Ra0.04~0.01 micron, mirror grinding can reach Ra 0.01 micron or less
Significance of grinding
1. Grinding is the oldest processing method of mankind
Grinding is a processing method that uses a large number of pitted tools to make objects finer and thinner through grinding, squeezing, friction, etc., in order to achieve the purpose.
2. Grinding is a sign that distinguishes the New and Paleolithic ages
Paleolithic Age: The main symbol is to make stone tools; about 2.5 million years ago, to about 10,000 years ago.
Neolithic Age: The main symbol is polished stone tools; it began about 10,000 years ago and ended in 5000-2000.
3. Grinding is indispensable in daily life
For example, stone mills, water mills, ceramics, electric mills, cosmetics, kitchen knives, teeth grinding, etc. in our lives, and parts of various household appliances need to be ground
4. Modern industry cannot do without grinding
With the development of machine tool equipment industry and abrasives, grinding accuracy, grinding efficiency and economy have been significantly improved, and grinding processing has gradually expanded to all processing fields in the national economy. At present, grinding has been widely used in various industrial fields such as rail transit, aerospace, cutting tools, semiconductor, bearing, gear, precision ceramic, military industry, electronic communication, equipment manufacturing, medical energy and so on.