How to make our shot blasting machine use the right projectile

　　The particle size of the projectile

　　To put it simply: crater depth and crater density are two key factors that affect the quality of cleaning, and the particle size of the projectile is the root of these two factors.

　　In detail: Although the impact force and coverage area of the larger particle size projectile are very important for the cleaning speed. However, on the premise of satisfying the cleaning quality, smaller particle size projectiles should be selected as much as possible to achieve a more efficient and high-quality surface cleaning effect.

　　projectile consumption

　　The consumption of the projectile is the weight of the unqualified projectile size discharged by the equipment, not the weight of each time the projectile is added. It measures whether the equipment design is reasonable and whether the adjustment is appropriate.

　　Projectile particle size selection method: It is best to estimate the smallest particle size with actual, and then attach the necessary larger projectiles until a suitable particle size range is found.

　　hardness of the projectile

　　The hardness of the projectile is a prerequisite for the bombardment force and rebound force, which directly affects the cleaning speed, the smoothness of the workpiece, and the quality of reinforcement.

　　Hardness is by definition a resistance to deformation, the harder the projectile, the greater the resistance to deformation and the more thorough the energy transfer.

　　In order to find the right strike force and prevent the workpiece from being damaged, it can be controlled by the following two points:

　　1. Select the appropriate projectile speed: different workpieces and processes require different speeds

　　2. Select the appropriate projectile hardness: Generally, the hardness of the projectile is 5-10HRC higher than that of the workpiece.

　　The ratio of projectiles

　　The ratio of projectiles is a mixture of projectiles of different sizes and shapes.

　　A high-efficiency pellet mix should contain large, medium, and small pellets.

　　①Large projectiles do loose work with high energy

　　② Thinner projectiles are used for lighter cleaning after loosening

　　③The fine projectile has high-density coverage for simple and quick surface refinement work

　　The choice of projectile size is determined by the state of the surface being cleaned

　　Although shot blasting can produce a more precise surface, it cannot make a rough surface into a more precise surface. The surface quality of the workpiece after shot blasting is restricted by the original surface condition before shot blasting. The quality of the cleaned surface (roughness grade) can usually be improved by one level. Reason: Using a relatively fine projectile to hit the surface of a relatively coarse part can turn one peak on the original surface into two smaller peaks and harden the surface; when the second time is thrown again, the surface becomes hard due to the It is not easy to hit the smaller peaks, and therefore does not provide precision.

　　The material of the projectile:

　　The material of the projectile is determined according to the material of the workpiece and the cleaning requirements, and is divided into hard projectiles and soft projectiles according to the surface treatment requirements. Hard projectiles are used for sand (shell), cleaning, strengthening, forming and other processes, and soft projectiles are used for surface degreasing, soot, paint and surface coating special processes.