Grinding is a material removal and surface generation process used to shape and finish components made of metals and other materials. The precision and surface finish obtained through grinding can be up to ten times better than with either turning or milling. Grinding employs an abrasive product, usually a rotating wheel brought into controlled contact with a work surface. The grinding wheel is composed of abrasive grains held together in a binder. These abrasive grains act as cutting tools, removing tiny chips of material from the work. As these abrasive grains wear and become dull, the added resistance leads to a worn out condition of the grinding wheel and it must then be replaced.
Grinding is a method of cutting, which utilizes an abrasive wheel for the purpose of efficiently and accurately cutting hard materials, such as aluminum, steel, and titanium. The abrasive wheel used in grinding is composed of abrasive grains that are held together by a binder. As these abrasive grains wear and become dull, the grinding action of the wheel is reduced due to the increased resistance encountered.
In grinding operations, the work piece is usually held in a fixture and then moved in continuous table strokes or oscillations. The feed and speed of the grinding wheel are both adjustable, which allows control of the cutting action. The feed rate is adjusted to allow removal of material and the wheel speed is adjusted to balance the removal rate. The wheel is usually connected to a motor and its speed is controlled.
The grinding process is composed of several steps. Initially, a wheel typically composed of a bonded abrasive or a combination of bonded and coated abrasives is used to remove material from the work surface. The grinding wheel is dressed with a vitrified or resin bond wheel dressing stick to remove abrasive grains from the wheel surface. This process is used to reset the wheel profile and expose new cutting edges. After the wheel is dressed, it is trued by rotating the wheel in a clockwise direction and moving it along the wheel face radially. This ensures that the wheel is symmetrically shaped and that the wheel is optimally performing its cutting action. The wheel will be used for grinding again once the wheel is trued and the wheel RPM is set.
Grinding is typically used for metal removal, deburring and finishing operations. Grinding processes can be characterized by the type of grinding wheel used. The majority of grinding wheels are vitrified, or ceramic bond, manufactured with abrasive grains generally selected according to the type of metal being ground and the required finish. Abrasive type, hardness, grain size and grade, and the bond type must all be considered when selecting the grinding wheel. Additionally, factors such as grinding environment, machine power, and material being worked must also be taken into account.
Grinding is one of the most important machining processes in modern manufacturing. It has high precision, rigidity and is suitable for processing hard objects, and for many years, it has been widely used to process high-precision mechanical parts. Grinding is a complex process, and the quality of the final product is largely determined by the grinding process. A good understanding of the principles of grinding can enable manufacturers to perfect the grinding process in order to achieve higher performance.
