Abstract: According to the invention, a press roller device (1) for molding a grooved structure inside a tubular workpiece (7) has several press rollers (4,5,6), said press rollers rotating around a form tool (2) and being staggered axially in relation to one another. At least two of the press rollers (4,5) are driven in opposite directions to each other. This arrangement prevents the workpiece from twisting to a large extent.

Abstract: The invention relates to a flowturning device (1; 101) for producing an internal geared wheel (17) with inner toothing, one set of which is slanted. The workpiece (9) is held by a retaining member (16; 116) during shaping of the first inner toothing. The workpiece (9) is held by the first toothing on the first shaping toot (2; 102) during shaping of the second inner toothing. Once the internal geared wheel (17) has been finished, the rotational coupling between both shaping tools (2, 4; 102, 104) is detached. The internal geared wheel (17) is detached from the slanted toothing(s) by means of a stripping member (18).

Abstract: A method for producing press-rolled tubes (3) with a press mandrel (1) and one or more pressure rollers (2), with the tube (3) being arranged between the press mandrel (1) and the pressure rollers (2) and being plastically deformed by means of force loading of the pressure rollers (2). To produce tubes with end wall thickenings, in a first working operation, a first press mandrel (1a) with a tailstock-end shoulder (4) is used. The pressure rollers (2) begin their transforming work at the tailstock-end shoulder (4) and work in the direction of the machine spindle. The half-finished tube (3a) is taken from the first press mandrel (1a), and, in a second working operation, the half-finished tube (3a) is clamped at the end with the wall thickening (5) which has already produced into a lathe chuck (6) (tensioning spindle or similar) mounted in the press-rolling machine, and a second press mandrel (1b), fastened on the tailstock end and having an outer diameter (d.sub.

Abstract: A prefabricated aeration block for silo bases in which at least two aeration blocks are mounted on the top side of a flat plate and shaped, hollow support sections are fixed on the bottom side of the plate, defining air channels for distribution of air to the aeration blocks.