F16K 3/085

Gate valves or sliding valves, i.e. cut-off apparatus with closing members having a sliding movement along the seat for opening and closing with flat sealing faces; Packings therefor with pivoted closure members in the form of closure plates arranged between supply and discharge passages with circular plates rotatable around their centres {the axis of supply passage and the axis of discharge passage being coaxial and parallel to the axis of rotation of the plates}