Abstract: A blast wheel having a rotatable shaft with discs carrying blades for propelling abrasive material against a surface to be blast-cleaned. Each one of the blades has a striking portion and a dovetail base member. Each one of the discs has a number of circumferential dovetail slots for receiving the base members of the blades. Keeper plates, lock washers and keeper bolts are used to retain each end of each blade in place. Each disc has several sound-abating holes to reduce the rotational noise of the blast wheel.

Abstract: A hand-held blast cleaning machine having a motor which serves as a handle. The machine includes a blast assembly for propelling abrasive material against a surface and a hopper for supplying abrasive material to the blast assembly. The blast assembly has a blast corridor, a rebound corridor, a blast opening, a blast wheel and a motor. The motor drives the rotation of the blast wheel and serves as a handle. The hopper has a return corridor, a collection area, a feed area and a vacuum conduit. The vacuum conduit is connected to a vacuum source to collect dust and debris from the blast cleaning operation. In one embodiment, an side-blast hopper, a down-blast hopper, an up-blast hopper and a side-feed hopper are all interchangeably attachable to the same blast assembly. A shut-off handle is attached to the blast assembly to provide automatic shut-off abrasive material to the blast wheel and to function as a second handle. In another embodiment, the motor serves as the only handle.

Abstract: A blast cleaning machine which gravity feeds abrasive material when blasting at positions from angularly upward to angularly downward. The machine includes a housing, a blast assembly, a motor for rotatably driving the blast assembly and a hopper. The housing has a blast corridor, a return corridor and a blast opening communicating with the blast corridor and the return corridor. The blast assembly receives abrasive material from the hopper and propels the abrasive material through the blast corridor and blast opening against the surface to be blast cleaned. The hopper has straight walls which are substantially parallel with the blast opening for gravity feeding abrasive material straight into the blast assembly. The walls of the hopper provide effective gravity feeding of abrasive material to the blast assembly when the machine is blasting anywhere between a 45-degree angle upward and a 45-degree downward.

Abstract: An apparatus for cleaning a surface comprises a truck with a hydraulic system and a trailer with a blast assembly, dust collector and electric power generator. The apparatus is configurable into an operating mode and a transport mode. In the operating mode, the apparatus is driven by means of the hydraulic system, the blast assembly is lowered to the surface by a hydraulic cylinder and the blast assembly extends beyond the width of the trailer to clean a wide area. Abrasive material is propelled against the surface by a plurality of motor-driven centrifugal blast wheels and is returned for reuse by a return auger and an elevator. Air flow created by the dust collector facilitates return of spent abrasive material for reuse. In another preferred embodiment, a recapture assembly is attached to the blast assembly to capture abrasive material escaping between the blast assembly and the surface to be cleaned.