Abstract: Sandblasting apparatus and valve apparatus therefor, and methods for performing sandblasting operations, wherein an abrasive-filled pressure vessel is pressured by sandblast air when an air control valve is opened, and wherein automatic blowdown of the pressure within the pressure vessel is required when the air control valve is closed, a dual valve structure being provided in which the air control valve and blowdown control valve are combined and in which the two valves operate in tandem, one valve being open when the other is closed.

Abstract: A blast room floor construction is disclosed, and the preferred and illustrated embodiment incorporates an overhead grate of substantial strength to enable a workman and work materials to be located thereon. The blast cleaning procedure forms a cloud of dust and residue which falls through the grate. Therebelow, multiple pieces are utilized to construct sloping, parallel sidewalls which form valleys. In each valley, there is located a hollow, rectangular vacuum tube. Vacuum is pulled through the tube. It has a number of holes formed in the tube which enable the sand and blast residue to flow through the holes into the tube, which are carried away for reuse. The valley is defined by adjacent sides of angle plate material. In addition, a diamond shaped sheet is folded across a diameter to define a pair of funnel surfaces where the diamond shape having notches formed in opposite corners to fit over the tube to carry the granular materials toward the hole in the tube.

Abstract: Valve apparatus for controlling flow of particulate material, such as sand or other abrasive material, from a tank or hopper. The valve has a unitary plunger which is movable axially with respect to a lateral particulate material inlet between positions closing and opening the inlet, the plunger being moved by rotation of a threaded portion of the plunger through an internally threaded cap or bonnet opening. The valve body passage through which the plunger is disposed, and the plunger itself, are formed to have abrasion-resistant surfaces. A lateral air pipe nipple sealed to the valve body receives the abrasive material flowing through the valve for use in sand blasting operations.