e the flow duct 25 is formed by a first cylindrical bore portion 26 in the interior of the cylindrical housing projection 30 a second bore portion 31 of the flow duct 25 is formed said bore portion having a diameter which is greater than that of the first cylindrical bore portion 26 between the second cylindrical bore portion 31 and the third bore portion 18 of the flow duct 25 in the region of the cylindrical central portion 29 of the valve housing 1 a cylindrical inner chamber is formed the diameter thereof being markedly greater than that of the second bore portion 31 the fluid outlet opening a is provided in a second end face cover part 28 on the side of the valve housing 1 remote from the first end face cover part between the first end face cover part 27 and the second end face cover part 28 extends a cylindrical central portion 29 of the valve housing 1 the two cover parts 27 28 are for example screwed to the cylindrical central portion 29 in the flow duct 25 a tubular valve sleeve 2 is arranged coaxially with the flow duct 25 between the second bore portion 31 and the fluid outlet opening a the valve sleeve 2 is configured to be of annular cross section and may be moved.