Abrasive Blasting Honolulu HI

The simplest description of abrasive blasting is the operation of preparing or giving particular textures to surfaces or cleaning surfaces using the sheer force of streams of abrasive materials. This process is synonymous to shot blasting, soda blasting, sand carving, sandblasting and glass bead blasting. It is a common procedure in the automotive industry, shipbuilding and most of the industries that do surface preparation as a prerequisite for painting.

The broad classes of blasting material are sand, slag, metallic grit or shot, synthetic and other. The properties and cost of abrasive materials is dependent on their application. Sand is common in cases where reclamation is infeasible. A good example of this is unconfined blasting operations. The high breakdown rate associated with sand results in high dust generation. Silicosis is the consequence of this. For this reason, sand blasters are not commonplace in shipbuilding. Smelter slag and coal are more than able substitutes in this industry. Slag has the advantage of low silica content although a few studies indicate that it releases harmful contaminants into the air. Metallic abrasives like cast iron, grit/shot are durable and should be reclaimed for reuse.

The synthetic kind is growing in popularity. Abrasives under this class, like aluminum oxide and silicon carbide, produce little dust. Just like their metallic counterparts, reclamation and reuse reduces production costs. The blanket category of others covers materials like crushed glass, glass beads, cut plastic, nutshells and mineral abrasive like staurolite, olivine and garnet. Their greatest advantage is that they produce less dust as compared to slag and sand abrasives. The blasting method dictates the abrasive used. Sand, alumina, silicon carbide and metallic shot/grit are the best candidates for dry blasting. Wet blasting requires materials that will remain in suspension in a liquid environment. Glass beads and sand are good materials in this respect.

The blasting operation includes three vital components: blasting nozzles, a propeller, and an abrasive container. The exact specification depends on the actual application and the abrasive used. Projecting the abrasive onto the surface is possible in three ways: water pressure, centrifugal wheels or air pressure.

Air blasting makes the use of compressed air, propelling the abrasive via either the pressure-type or suction type process. The first process uses very high forces, transmitting the abrasive via a blast hose. The other type creates a vacuum in the blast gun of the system, which pulls the abrasive and directs it to the surface via a blast nozzle. In all cases, compressed air has to be free from traces of moisture and oil. The latter contaminates the abrasive and surface itself while the former causes pot clogging and flash rusting. It is important to ensure that the air supply suits the application at hand. Compressor characteristics, loss of pressure by the fittings and hoses and nozzle wear all demand attention.

The centrifugal option uses a rotating impeller that mechanically propels the material on to the surface. A combination of inertial forces and centrifugal forces does the trick. The water pressure method (sometimes referred to as the wet method) uses either air pressure or water pressure to propel abrasive slurry on to the surface.

Additional equipment is available to assist operators. Locating abrasive traps in the extraction duct facilitate the collection of reusable material. The reduction in wear of the collector filters and abrasive consumption are valuable bonuses. Dust collectors limit emission in to the air, maintaining a clean, safe environment. Setting the air separator to an optimum level has an equally important role to play. It removes contaminants and spent abrasive, as well as maintaining a constant mix by rejecting particles that fall under the adjusted value.