Abstract: The present invention relates to an improved immediate action chemical injection system for selectively adding a chemical solution to the high velocity water spray discharged by a high pressure water washer. A common supply conduit has an inlet end adaptable for engagement with a low pressure source of water and has a first outlet end attached to the inlet of the high pressure water delivery system of the washer and a second outlet end attached to a completely separate chemical injection system. The high pressure water delivery system emits a spray of highly pressurized water having a substantially fan-shaped pattern which is intersected by a spray of chemical solution emitted from the chemical injection system, with the result being a high velocity spray of water and chemical being provided for use against a work surface.

Abstract: A particulate spray nozzle is disclosed having an internal mixing chamber with a liquid spray orifice on one side and a liquid and particulate discharge bore opening the opposite side to ambience. A liquid supply passage upstream of the orifice contains a disc-like diffuser with the plane of the disc parallel to and aligned with the longitudinal axis of the orifice. The diffuser is spaced axially from the orifice and the orifice is spaced axially from the discharge bore for causing a high pressure liquid to be discharged from the orifice in the form of a narrow gradually diverging spray which picks up particulate material in the mixing chamber and propels it out of the discharge bore by uniformly engaging only the outer most portion of the discharge bore. The apparatus can function as an abrasive blasting assembly or a chemical foaming gun. A method of discharging particulate materials, which may be either solid or liquid, is also disclosed.

Abstract: A control apparatus for a sand blasting nozzle is shown having means to induce a suction in the sand delivery conduit associated with the nozzle. A sliding valve structure for controlling the induced vacuum in the sand delivery conduit is provided along with a valve for controlling flow of the fluid medium for impelling the sand. The system makes use of high velocity air or steam or high pressure water or similar fluid for inducing the required suction in the sand delivery line and for driving the sand against the object to be blasted. Handle means form part of the apparatus to control the direction of the stream of abrasive and carrier fluid blasted from the nozzle portion of the assembly.