Suction type
High pressure air is jetted toward a nozzle tip by an air jet nozzle. A ejector phenomenon occurs at the time.By power of absorption by ejector phenominon, breathe in abrasives in a nozzle through a blast hose and jets abrasives from a nozzle tip.
The diameter of the nozzle tip generally increases twice as much as the diameter of the air jet nozzle. As a result, the grinding material can be inhaled.
The high pressure air which was jetted by an air jet nozzle is in the nozzle tip while taking in the air of the circumference. The abrasives jetted by a nozzle tip tend to spread so that the high pressure air is jetted with abrasives. If the diameter of the nozzle tip becomes big by the abrasion of the nozzle tip,the jetted abrasives spread more, and ability for cut falls.
Alumina or boron calcium carbide is used for the materials of the nozzle tip because it is hard to be worn.
The structure of the suction type is simple and generally used.