1) There are following mechanical metal cleaning methods.

1. Wiping
   Manually or mechanically wipe off with cloth or buff material
2. Grinding and Machining
   Grind with buffs or belts made of cloth or paper with abrasives. Mill surfaces of cast products.
3. Blasting
   Silica sand, steel grits and glass beads are air sprayed or projected with rotating wheels (Centrifugal projection)
4. Hydro blasting
   Alumina and silicon carbide particles mixed in water are sprayed ([Fig.1])
5. Other, Tumbling barrels, rotary wire brush, etc.

2) Applicable areas

1. Scales from high temp. processes
2. Rust and sand removal from cast surfaces
3. Removal of high temp. baked paints
4. Various burrs and contaminants on casting molds and dies
5. Removal of rust and paints from repaired parts
6. Preparations for painting, thermal spraying and Teflon coating, decorative surface roughing
7. Partial repairs of other surface finishing processes

3) Characteristics

This method is characterized by its ability to: completely process, wide applicability, partially applicable, and fast processing speed. Other than cleaning, the process can also be applied to removal of surface defects and decorative processes.