a cleaning operation applicable to large castings, in which a high-velocity air blast is used to carry the metallic shot, the latter being the effective abrasive. The method is especially useful where burnt-on sand or scale is to be removed. The "shot" consist of angular chilled iron and steel and these have replaced silica as the abrasive used in blasting work. The air pressure varies ..., dependent on the type of metal treated ...
cleaning and descaling metal by shot peening or by means of a stream of abrasive powder blown through a nozzle under air pressure in the range 30-150 pounds per square inch
