Patent ID: 7101266

Claim:
The device for the abrasive blasting comprising: (a) a nozzle gun ( 10 ), comprising: a cylindrical body ( 102 ) with an air-cooling chamber ( 104 ) formed by a sleeve ( 106 ) with a solid wall installed to form a maze, a combustion chamber ( 108 ) with a perforated wall ( 112 ) and a tubular element ( 114 ) for air/abrasive mixture feeding connected to a feeding tube ( 120 ) located concentrically and fastened to each other; a swirler ( 124 ) for the gaseous oxidant for preparing of the fuel blend, equipped with spiral grooves communicating with compressed air feeding pipe ( 116 ); orifices ( 162 ) connected with liquid fuel feeding pipe ( 118 ) located on the combustion chamber input between the latter's perforated wall and the tubular element; an output nozzle ( 128 ) equipped with a means for axial displacement and fastening to the cylindrical body communicating with the air cooling chamber; an ignition spark plug ( 132 ) located in the combustion chamber; (b) a tank ( 40 ) for the liquid fuel the output of which communicates to the liquid fuel feeding pipe to the nozzle gun combustion chamber; (c) an air/abrasive mixer comprising a vessel ( 20 ) for abrasive, the output tube of which is connected through a batcher ( 21 ) to an ejection-type mixer ( 22 ) communicating to the air/abrasive channel feeding pipe of the nozzle gun; (d) a receiver ( 30 ) with a feeding pipe for connection to the compressed air source communicating to said vessel ( 20 ) for abrasive and liquid fuel tank ( 40 ), with the ejector pipe of the mixer and with the compressed air channel feeding pipe of the nozzle gun, wherein the nozzle gun (a) ( 10 ) comprises a swirler ( 122 ) of the fuel blend, while the combustion chamber ( 108 ) at its perforated wall area ( 110 ) is embodied with variable cross-section and possesses at least one area ( 136 , 138 ) narrowing with respect to end cylindrical sections ( 140 , 142 ); the input part ( 146 ) of the tubular element ( 114 ) for air/abrasive mixture feeding is fastened to the body through two cylindrical spacers ( 148 , 150 ) located concentrically forming between them the annular cavity ( 152 ) for fuel feeding to the fuel blend swirler ( 122 ); the first said cylindrical element ( 148 ) possesses at one end a counterbore ( 154 ) for fastening of the flange of the tubular element input part, and on the other end, the through spiral grooves ( 164 ) on the external surface operating as the fuel blend swirler; the second said cylindrical element ( 150 ) possesses a lateral channel ( 158 ) connected to the liquid fuel feeding pipe ( 118 ) to said cavity, the external threaded part ( 194 ) for fastening of the body, the counterbore ( 161 ) for fastening the cooling chamber sleeve, and orifices ( 162 ) connecting said cavity ( 152 ) to the air cooling chamber ( 104 ).