Sand blasting is a metal surface mechanical treatment technology widely used in rubber production. The basic principle of sand blasting is to use sand, steel balls, glass beads, etc., with compressed air of 0.5~0.6MPa, and spray it onto the surface of the workpiece to be treated, and use high-speed jets of sand, steel balls or glass beads to remove the surface of the workpiece. Rust, oxide and other contaminants make the bond between the rubber grommets and the metal stronger.
The purpose of sand blasting is as follows:
- remove rust spots, welding slag, carbon deposits and other contaminants on the surface of the skeleton;
- Make the surface of the skeleton rougher and increase the bonding area with the rubber grommets.
- removing the oxide layer on the surface of the skeleton;
- to remove the burrs and directional marks (such as tensile marks, scratch marks, etc.) formed during the processing of the skeleton;
- Commercially decorated the surface of the outer skeleton by sandblasting.
Sandblasting requirements: After the sandblasted metal skeleton, there shall be no rust marks or burrs on the surface; the treated skeleton shall not be deformed; the surface roughness shall conform to the process requirements; after sandblasting, the skeleton shall be The diameter dimensions, especially the aluminum alloy casing of the shock absorber, shall not exceed the tolerances required by the drawings.
Sand blasting is divided into dry blasting and wet blasting. Sandblasting the skeleton is mainly done by dry blasting. The methods of sand blasting include injection type, pressure feed type, projectile type (also called centrifugal sand blasting method), and dust-free blasting type.
The metal skeleton after sandblasting should be bonded to the rubber product as soon as possible to avoid secondary oxidation and contamination of the surface.