Fluid-actuated rotary drive

The drive has a cover (34) with opposite through passages (43a, 43b) fitted to the hood (33) so that through passages (42a, 42b) in the hood and those in the cover form two through passage pairs (53, 54) partly aligned with each other. A centering piece (56, 57) is fitted in each pair, by which the cover and hood are held together.