Patent ID: 8821213

Claim:
An abrasive jet system configured to remove at least a portion of a target material with an abrasive waterjet, the abrasive jet system comprising: a piercing device having a mixing tube having a first axial passage through which the abrasive waterjet travels, the abrasive waterjet including pressurized water and abrasives; a secondary tube having a second axial passage through which the abrasive waterjet travels, wherein the second axial passage is axially aligned with the first axial passage; an exit for the abrasive waterjet; a holding device positioning the mixing tube relative to the secondary tube; an opening in an outer surface of the holding device; and an air passage extending from the opening through at least a portion of the holding device to a location generally positioned between an outlet of the mixing tube and an inlet of the secondary tube, wherein the location is upstream of the exit and downstream of any mixing region in which the abrasive waterjet is formed by mixing the pressurized water with the abrasives, wherein the air passage is configured to allow air entering through the opening to flow into the abrasive waterjet.