GB1040062A - Improvements in and relating to abrasive guns - Google Patents

Abstract

1,040,062. Blasting. ABRASIVE DEVELOPMENTS Ltd. Jan. 10, 1964 [Jan. 31, 1963], No. 3960/63. Heading B3D. An abrading device comprises a gun for delivering a blast of a mixture of abrasive, liquid and gas and comprising a feed chamber for receiving a slurry of the abrasive and liquid, the feed chamber having an entry for the slurry, a tubular mixing chamber, an inlet connection at one end of the mixing chamber outside the feed chamber, an outlet at the other end of the mixing chamber, the outlet constituting, or being arranged to be connected to, an outlet nozzle, and at least one aperture in the tubular wall of the mixing chamber opening into the feed chamber for the passage of slurry from the feed chamber to the mixing chamber, slurry supply means connected to said entry, and means for connecting said connection to a pressurized source of the gas. A slurry feed chamber 11 formed in the gun body 10 has an entry 12 continued as a bore 13 in a handle portion 14 coupled at its outer end to a supply pipe from a source of supply of slurry under pressure. A casehardened tube 16 extending through the end walls of the chamber 11 has an inlet connection 17 for coupling to an air supply pipe. The tube 16 is removably retained by a nut 22; gaskets 19, 23 are provided. The tube 16 has two apertures 25, 25, communicating with the chamber 11. The outlet end of the tube 16 is extended by a replaceable nozzle 26 either of low wearresistant metal or of high wear-resistant metal, retained by a flange 29 on the nut 22 and a rubber or like sealing bush 30. The slurry is fed by a pump at 70-75 p.s.i. The air pressure is higher than the slurry pressure but not more than 25% above it.