Non-return valve with flexible collar - has ribs in valve bore to support collar in valve open position

摘要

A non-return valve has a body (1) with a bolted on inlet flange (2) which supports a streamlined core (3) by means of radial ribs. a flexible collar (5) is clamped between the body (1) and the outlet flange (2). The thin outer end of the flexible collar (5) is normally in contact with the core (3) by is expanded by the flow of fluid and pressed against ribs (6), which are spaced around the bore of the body (1). If the upstream pressure falls, flow reversal is prevented by the pressure in the spaces between the ribs (6) pressing the collar (5) against the core (3).