Patent ID: 9103465
Filing Date: 2015-08-11
Classification: F16K

Abstract:
1. A gate valve actuator, comprising: a housing; a first piston movably disposed in the housing, wherein the first piston comprises an outer shoulder formed on an outer diameter of the first piston that is configured to engage an inner shoulder formed on an inner diameter of the housing to limit movement of the first piston in a first direction; a second piston movably disposed in a bore of the first piston, wherein the second piston is movable in the first direction after engagement between with the outer shoulder of the first piston and the inner shoulder of the housing; a biasing member disposed in the housing and configured to bias the first and second pistons in a second direction that is opposite the first direction; a retaining plate disposed in the housing and configured to retain one end of the biasing member; and a retaining nut disposed in the housing and coupled to the retaining plate, wherein the second piston is moveable into engagement with the retaining nut to compress the biasing member via the retaining plate.