Sandblasting

Tuesday, September 9, 2008

Sandblasting or bead blasting is a generic term for the process of smoothing, shaping and cleaning a hard surface by forcing solid particles across that surface at high speeds; the effect is similar to that of using sandpaper, but provides a more even finish with no problems at corners or crannies. Sandblasting can occur naturally, usually as a result of particles blown by wind causing eolian erosion, or artificially, using compressed air. An artificial sandblasting process was patented by Benjamin Chew Tilghman on October 18, 1870.

Historically, the material used for artificial sandblasting was sand that had been sieved to a uniform size. The silica dust produced in the sandblasting process caused silicosis after sustained inhalation of dust. Several countries and territories now regulate sandblasting such that it may only be performed in a controlled environment using ventilation, protective clothing and breathing air supply (as shown in the top image).

Other materials for sandblasting have been developed to be used instead of sand; for example, carborundum grit, steel shots, copper slag, powdered slag, glass beads (bead blasting), metal pellets, dry ice, garnet^[1], powdered abrasives of various grades, and even ground coconut shells, corncobs, walnut shells, and baking soda (sodablasting) have been used for specific applications and can produce distinct surface finishes. Some commercial grade blasters are specially designed to handle multiple blast abrasives. These blasters are commonly referred as multi-media blasters.

Sandblasting can also be used to produce three dimensional signage. This type of signage is considered to be a higher end product as compared to the flat signs. These signs often incorporate gold leaf overlay and sometimes crushed glass backgrounds which is called smalts.

Sandblasting can be used to refurbish buildings or create works of art (carved or frosted glass). Modern masks and resists facilitate this process, producing accurate results.

Sandblasting technique is used for cleaning boat hulls, bricks, and concrete work. Sandblasting which is also known as blast cleaning is used for cleaning industrial as well as commercial structures.