What Is Shot Blasting?

Shot blasting is both the name of a mechanical surface treatment process and a name for acrobatic activities.

[po wán]

Shot blasting is both a mechanical aspect

(po wán) English name: shot blast

Acrobatic one. Tossing multiple projectiles on both hands does not land.

Shot blasting is also the name of a mechanical surface treatment process. Similar processes include sand blasting and shot blasting. Shot blasting is a cold treatment process, which is divided into shot blast cleaning and shot peening. As the name suggests, shot blasting is to remove impurities such as surface oxide scale and improve appearance quality. Shot peening is the use of high-speed moving projectile (60-110m / s) flow Continuous impact is strengthened on the surface of the workpiece, forcing the target surface and surface layer (0.10-0.85mm) to undergo the following changes during the cyclic deformation process: 1. the microstructure is modified; 2. non-uniform plastic deformation, the outer surface introduces residuals Compressive stress, residual tensile stress occurs on the inner surface layer; 3. the outer surface roughness changes (Ra Rz). Impact: It can improve the fatigue fracture resistance of materials / parts, prevent fatigue failure, plastic deformation and brittle fracture, and improve fatigue life.

Shot blasting principle

The double discs in the shot blaster are riveted together to form an impeller body. The impeller body is equipped with eight blades, and the impeller body and the dividing wheel located in the center of the shot blasting wheel

Shot blaster

Together mounted on a spindle driven by a motor. The cover is lined with a protective plate, and the cover is equipped with a directional sleeve and a pill feeding tube. During work, the projectile flows into the shot blaster from the shot tube. The dividing wheel which rotates synchronously with the blades enables the projectile to obtain the initial velocity. The projectile flew out through the window of the directional sleeve and was thrown on the high-speed rotating blade outside the directional sleeve. After being further accelerated by the blade, it was projected on the surface of the workpiece to be cleaned. The synchronous rotation of the dividing wheel and the blade ensures the vibration-free transmission of the projectile to the blade, thereby reducing the wear on the blade.

The principle of shot blasting is to use an electric motor to drive the impeller to rotate (directly driven or driven by a V-belt), and rely on the action of centrifugal force to make the projectile with a diameter of about 0.2 to 3.0 (the cast steel shot, wire cut shot, stainless steel shot, etc. different Type) Throw it on the surface of the workpiece to make the surface of the workpiece reach a certain roughness and make the workpiece beautiful, or change the welding tensile stress of the workpiece to compressive stress to increase the service life of the workpiece. By improving the surface finish of the workpiece, the paint film adhesion of subsequent painting of the workpiece is also improved. Shot blasting is used in almost all areas of machinery, such as shipbuilding, automobile parts, aircraft parts, gun and tank surfaces, bridges, steel structures, glass, steel profiles, anti-corrosion of inner and outer walls of pipes, and even road surfaces. .

Shot blasting machine adjustment

Before using the new shot blasting machine, the position of the directional sleeve window must be adjusted correctly, so that as many projectiles are thrown as possible on the surface of the workpiece to be cleaned to ensure the cleaning effect and reduce the wear on the wear-resistant parts of the cleaning chamber. The position of the directional sleeve window can be adjusted by referring to the manual.

Shot blasting material

Common shot blasting materials are steel shot, aluminum shot, ceramic powder, steel sand, walnut sand, corn cob, glass beads, resin sand, plastic sand, etc.