Abstract: Apparatus for treating a workpiece has first and second regions at least partially enclosed by a casing and in communication via a passage, and support means for a carrier holding the workpiece in the first region for treatment. Pressure difference between the regions forces the workpiece toward the carrier and guides a flow of media from the first to the second region through the passage, at least partly, to create said pressure difference. Method for treating at least one workpiece holds the workpiece by forcing it toward the carrier with a created pressure difference between two regions. Holding also guides a flow of media from the first region to the second region through the passage in order to, at least partly, create said pressure difference. The treatment may comprise blasting, rinsing or drying. The workpiece may comprise cutting inserts, electronic components, small sized machined or formed components or parts.

Abstract: A wet-blast machine (1) with a closed-cycle re-use system (2) incorporates apparatus (3) for conveying loose particulate (abrasive) wet-blast material (4) present in a body of water (5). The apparatus (3) comprises a longitudinally extending trough (6), for containing the water (5) and particulate material (4), a support structure (7) movable in a reciprocating manner within the trough (6), and a row of longitudinally spaced flap members (8) attached to and depending from the support structure (7). When the support structure (7) is reciprocated, wave motions are created in the water (5), which move the loose particulate material (4) in a predetermined direction along the trough (6), namely toward a collection point provided by a chute (10).

Abstract: A centrifugal pump for pumping a mixture of abrasive particles in a liquid has a casing affording a cylindrical pumping chamber with an inlet and outlet, and an impeller of circular form disposed in the chamber for rotation about the longitudinal axis thereof, with radially extending vanes for drawing the mixture into the chamber through the inlet and expelling it via the outlet, the dimensions of the impeller and pumping chamber being such that the clearances between the impeller and chamber wall are small. The inside wall of the chamber, and the impeller carry an outer layer of rubber or like abrasive-resistant material.