| 摘要 |
<p>Gate valve comprising a valve body (1) with two coaxial openings (12, 13) equipped with means (14, 15) for connection to a pipe, an operating rod (2), a closure face (10) and an opposite closure face (11), characterised in that the closure face (10) comprises a recess (17), emerging on both sides of the closure face and equipped with a piston (18), which is moveable between on one side a single abutment (19) and on the other side a shoulder (20) of the recess, the pressure of the piston against said shoulder comprising sealing means (21), a return spring (23) pushing said piston towards said single abutment, said piston comprising, on the side nearest to said single abutment, means (24) for interaction with an inclined slope (26) on said operating rod (2) which, when the valve is closed, push the piston against said shoulder (20) of the recess. …<IMAGE>… </p> |
