Sand belt grinding is a new process that uses sand belts to gradually remove or smooth the excess material on the machined surface of the workpiece by contacting the high-speed running sand belt with the workpiece surface in a corresponding way and under a certain pressure, according to the requirements of the workpiece to be machined on a certain mechanical device. During the relative motion between the abrasive particles and the workpiece surface, there is a certain degree of interference between the abrasive particles and the workpiece surface. According to the degree of interference, it can be divided into three different processes.
(1) Sliding friction actually begins to contact the workpiece at this point, with little interference. The abrasive particles only rub against the surface of the workpiece, playing a "sliding friction" role. At this time, the abrasive particles slide on the workpiece, actually producing elastic and plastic deformation of the material being cut off.
(2) With the feed of the machine tool and the increase of cutting thickness, the interference of the plow increases. At this time, the abrasive particles plow "grooves" on the surface of the workpiece, which is called the "plow". At this time, the workpiece material undergoes plastic flow, and the material undergoes a squeezing motion, squeezing out from the front and both sides in the direction below the abrasive grain, while cutting off a small amount of material.
(3) Under a certain pressure, when there is sufficient interference and accompanied by a certain cutting temperature, true "cutting" begins. At this time, fractures occur in front of the sliding abrasive particles, forming chips with a relatively fast cutting rate. The numerous abrasive particles on the sanding belt, at the moment of contact with the workpiece, some of the abrasive particles perform cutting, others plow out grooves, and some only play a sliding role. Even different parts of the same abrasive particle and the same part play different roles at different processing times. In addition, the rotational motion of the sand belt also plays a role in wiping away the chips, removing the chips in front of the advancing abrasive particles.