Shot blasting rust remover is a method which mainly uses the high-speed operation of mechanical equipment, throws steel shots with a certain particle size through the centrifugal force of throwing the head, and the thrown steel shots collide violently with the components to achieve the purpose of removing rust on the steel surface. There are two kinds of steel shot used: cast iron shot and steel wire cut shot. Cast iron shot is an iron shot with a particle size of 0.8 ~ 5 mm formed by hot metal spraying and rapid cooling, and its surface is very round. It is relatively cheap, but it is not very durable. In the process of shot blasting, iron shot is broken by repeated impact and discharged as dust. Shot blasting cutting of steel wire is to cut the steel wire of waste steel wire rope into small pieces of 2mm, and its surface has sharp corners, so the derusting effect is relatively high, it is not easy to break, the service life is prolonged, but the price is increased. The latter's shot blasting surface is rougher.

Sand blasting derusting machine is a kind of derusting method which uses high-pressure air to take out quartz sand and spray it on the surface of components. The sources of quartz sand are: river sand, sea sand and artificial sand. Sand has low cost and wide sources, but it pollutes the environment. Derusting depends entirely on manual operation, and the surface roughness of the parts after derusting is small, so it is not easy to meet the requirements of friction coefficient. Sea sand should be desalted before use.

The above two rust removal methods require that the ambient humidity be less than 85%. Derusting grade standard of rust remover requires that the national standard GB 8923-88 "Steel Surface Modification Grade and Derusting Grade Before Painting" divides the derusting grade into three types: spraying or throwing derusting, manual and power derusting and flame derusting. Spray or projectile derusting, represented by the letter "Sa". There are four grades:

Sa 1 mild spray or projectile derusting. There is no visible grease or dirt on the steel surface, and there are no attachments such as scale, rust and paint coating that are not firmly attached.

Sa2 Thoroughly spray or rust. There should be no visible grease, dirt, scale, rust and other attachments on the steel surface, and the residue should be firmly attached. When the dents formed by shot peening are evenly distributed on the steel surface, the anti-skid coefficient is 0.35 ~ 0.45.

Sa2.5 Spray or spray rust very thoroughly. There should be no visible attachments on the steel surface, such as grease, dirt, scale, rust and paint coating, and any remaining traces can only be slight spots in spots or stripes. When the dents formed by shot peening are evenly distributed on the steel surface, the anti-skid coefficient is 0.45 ~ 0.5.

Sa3 spray or projectile derusting to clean the steel surface. The steel surface should be free of visible grease, dirt, scale, rust and paint, and the surface should present a uniform metallic luster.