What is the difference between shot blasting steel shot and sand blasting steel shot?

　　Shot blasting - using a motor to drive the impeller to rotate, relying on the centrifugal force, the diameter of 0.2~3.0 steel shot and steel sand (including alloy shot, wire cut shot, stainless steel shot, steel shot and steel sand, etc.) is thrown onto the surface of the workpiece, so that the surface of the workpiece reaches a certain roughness, making the workpiece beautiful, or changing the welding tensile stress of the workpiece to compressive stress, and improving the service life of the workpiece. It is used in almost most fields of machinery, shipbuilding, automobile parts, aircraft parts, gun and tank surfaces, bridges, steel structures, glass, steel plates, pipelines, etc. Sand blasting (shot) - using compressed air as a power to spray steel sand with a diameter of 40~120 mesh or steel shot of about 0.1~2.0 onto the surface of the workpiece, so that the workpiece achieves the same effect. The size of the steel shot is different, and the treatment effect achieved is different. It is emphasized that shot blasting can also play a role in strengthening. Now the domestic equipment has entered a misunderstanding, thinking that only shot blasting can achieve the purpose of strengthening. American and Japanese companies use both shot blasting and shot blasting for strengthening. Each has its own advantages. For example, for workpieces like gears, the shot angle of shot blasting cannot be changed, and the initial speed can only be changed by frequency conversion. However, it processes a large amount and a fast speed, while shot peening is just the opposite, and the effect of shot blasting is not as good as that of shot peening. Sandblasting is a method of cleaning the surface of parts by blowing quartz sand out at high speed with compressed air. It is also called sand blowing in the factory. It not only removes rust, but also removes oil, which is very useful for painting. It is often used to remove rust on the surface of parts; in steel structures, the use of high-strength bolts for connection is a relatively advanced method. Since high-strength connections use friction between the bonding surfaces to transmit force, the quality requirements of the bonding surfaces are very high. At this time, the bonding surfaces must be treated with sandblasting.