Sandblasting with pellets of material capable of sublimation
Particle-blast cleaning apparatus and method
Method and apparatus for producing carbon dioxide units
Method and apparatus for the treatment of work pieces by shot blasting
Particle blast cleaning apparatus
Phase change injection nozzle
Noise attenuating supersonic nozzle
Method for deflashing articles
Particulate delivery system
ApplicationNo. 007518 filed on 01/22/1993
US Classes:451/7, Controlling temperature451/39, With nonsiliceous abradant451/40, With nonatmospheric fluid carrier451/75, Sandblast451/90Having hand-directed sandblast nozzle
ExaminersPrimary: Kisliuk, Bruce M.
Assistant: Morgan, Eileen P.
Attorney, Agent or Firm
International ClassesB24B 049/14
AbstractA system and method for cleaning or removing coatings, such as paint, from a surface with a stream of particles. A carbon dioxide (CO2) pelletizer forms carbon dioxide pellets, which are delivered by a delivery system against a surface to be cleaned. The delivery system includes a hopper for containing the pellets and a high pressure air supply. A feeder introduces the pellets from the hopper into the high pressure air. The combined high pressure air and pellets are directed along a delivery hose to a nozzle, which directs the air and pellets against a surface to be cleaned. Temperature sensors are provided to monitor the temperature of the pressurized air at various points in the delivery system. Signals from the temperature sensor are provided in a feedback control manner to a control valve. The control valve controls the introduction of liquid nitrogen (N2) into the air stream at a mixing chamber in the delivery system. In accordance with the invention, the temperature sensors and feedback controls permit maintenance of the temperature of the high pressure air below the sublimation temperature of the pellets as the pellets are delivered by the delivery system, thereby prolonging the life of the pellets and reducing sublimation prior to ejection from the nozzle.