Sand blasting is a method to clean 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 can not only remove rust, but also remove oil. It is very useful for coating. It is often used for rust removal on the surface of parts; Finish the surface of parts (this is the use of small wet sand blasting machine sold in the market. The sand is usually corundum and the medium is water); Dalian sandblasting and shot blasting in steel construction, using high-strength bolts for connection is a relatively progressive method. Because high-strength connection uses the friction between joint surfaces to transfer force, it has high requirements for the quality of joint surface. At this time, sandblasting must be used to treat the joint surface.