Cryogen shot blast deflashing system

A cryogen shot blast apparatus for deflashing work pieces, said apparatus comprising:

• a treatment chamber for the work pieces;
• a throwing wheel adapted to propel particulate media into the treatment chamber to impact the work pieces in the treatment chamber;
• a cryogen supply system for introducing a flow of cryogen into the treatment chamber for embrittling at least selected portions of the work pieces in the treatment chamber;
• a recirculation system including a separator unit in communication with the treatment chamber, a withdrawal conduit in communication with said treatment chamber, a supply conduit connecting said withdrawal conduit and said throwing wheel to return pressurized cryogen gas to said throwing wheel, and a main blower connected to said withdrawal conduit for withdrawing cryogen gas from the treatment chamber and connected to said supply conduit for returning pressurized cryogen gas to said throwing wheel;
• a drop chute connecting said treatment chamber and said recirculation system to direct particulate from said treatment chamber to said separator unit, said drop chute having a downwardly sloped upper surface toward said separator unit and a plurality of spaced-apart openings along said upper surface for introducing streams of pressurized gas to assist movement of particulate through said drop chute from said treatment chamber to said recirculation system;
• and
• a particulate media supply system for introducing a metered flow of particulate media into flowing cryogen gas in said supply conduit to transport particulate media to said throwing wheel.

A cryogen shot blast apparatus for deflashing work pieces, said apparatus comprising:

• a cryogenic chamber;
• a barrel supported within said cryogenic chamber and defining a treatment chamber for the work pieces, said barrel being rotatable about a longitudinal axis and pivotable to a dumping position wherein work pieces in said barrel are dumped from said barrel through an open end of said barrel;
• a throwing wheel adapted to propel particulate media into the treatment chamber to impact the work pieces in the treatment chamber;
• a cryogen supply system for introducing a flow of cryogen into the treatment chamber for embrittling at least selected portions of the work pieces in the treatment chamber;
• a recirculation system including a separator unit in communication with the treatment chamber, a withdrawal conduit in communication with said treatment chamber, a supply conduit connecting said withdrawal conduit and said throwing wheel to return pressurized cryogen gas to said throwing wheel, and a main blower connected to said withdrawal conduit for withdrawing cryogen gas from the treatment chamber and connected to said supply conduit for returning pressurized cryogen gas to said throwing wheel;
• a drop chute connecting said cryogenic chamber and said recirculation system to direct particulate from said treatment chamber to said separator unit, said drop chute having a downwardly sloped upper surface toward said separator unit;
• a spacer located above said drop chute;
• wherein said spacer includes a main rod having a central portion spaced from said upper surface and a plurality of spaced apart fingers extending between said upper surface and said main rod;
• and
• a particulate media supply system for introducing a metered flow of particulate media into flowing cryogen gas in said supply conduit to transport particulate media to said throwing wheel.