Abstract: A pair of expansion links each having a rotary jet nozzle are respectively expanded in the opposite two directions in synchronism with each other within a tank. With these link mechanisms capable of expansion and contraction, the link arms forming the links can be closed until the link arms are parallely adjoined to one another. The link mechanisms are driven by a driving shaft from outside the tank. The inner surface of the tank is scanned with streams of water sprayed from the nozzles along with the expansion of the expansion links thereby cleaning the inner surface of the tank.

Abstract: A roller burnishing device for sizing and/or finishing the external surface of a workpiece having a circular sectional contour by causing a relative rotation between the workpiece and a plurality of truncated conical rollers arranged within a head having a truncated conical inner surface. In this device, the head is made nonrotatable and instead a hollow cylindrical cage supporting the rollers within the head is driven in rotation to rotate the rollers at a high speed and the rollers are caused to orbit by driving the cage in low speed rotation thereby causing the rollers to make a planetary motion within the head.

Abstract: A superhigh pressure fluid injection apparatus causes a fine jet streamline flow of superhigh pressure fluid to make a circular motion by utilizing a part of the supplied high pressure fluid. The apparatus includes an eccentric rotary member (3) for eccentrically rotating a nozzle (5), and a hydraulic motor (2) for driving the rotary member (3) into rotation by utilizing a part of the supplied high pressure fluid to the nozzle (5).