Fluid pipeline non-return valve damper - has cylindrical sliding guide piece supporting damper piston and with variable throttle openings

摘要

The damper is for a non-return valve in a pipe handling fluid, having a plug moved by the fluid flow and bearing against a seat when shut. A damping piston engages positively with the plug shortly before this shuts, and is of hollow cylindrical section. At the ends (12, 13) of the piston (11) are cylindrical chambers, separated from the inner chamber through which the fluid flows by a hollow cylindrical guide piece (10), movable axially and supporting the piston. The variable cross-section throttle openings (16, 17) connecting the chambers together are formed in the guide piece. The axial position of these throttle openings can be such that when the damping piston is in the end position with the valve shut only part of the cross-section of openings (17) is in line with the respective chamber (15).