Fail safe gate valves and actuators therefor

Patent · Tue Sep 08 04:00:00 EDT 1987

OSTI ID:5826253

Akkerman, N H; Vazquez, G

A fail safe valve is described comprising a body having a flowway therethrough and a closure member movable between positions opening and closing the flowway. There is an actuator having a stem including one portion connected to the closure member and mounted for reciprocation in opposite directions to move the closure member between the positions. The piston means are responsive to the supply of a control fluid for urging the one stem portion in one direction to move the closure member to one position and maintain it in that position as long as the control fluid is maintained at a predetermined pressure level. Means for yieldably urge the one stem portion in the other direction to move the closure member to its other position in the event the control fluid is not so maintained. Operating means mounted on the actuator and manipulatable from the exterior move another portion of the stem in the one direction to move the closure member to its one position. Means are provided for automatically responding to the failure of a predetermined environmental temperature condition for rendering the operating means inoperative to move the other portion of the stem in the one direction upon reestablishment of the control fluid to the piston means at the predetermined pressure level.

• Assignee: AVA International Corp., Houston, TX
• Patent Number(s): US 4691893
• OSTI ID: 5826253
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
420205* -- Engineering-- Transport & Storage Facilities-- (1980-)
ACTUATORS
AUTOMATION
CONTROL
CONTROL EQUIPMENT
DESIGN
EQUIPMENT
FAILURES
FLOW REGULATORS
FLUID FLOW
FLUIDS
LIQUID FLOW
OPERATION
ORIENTATION
PISTONS
POSITIONING
RELIEF VALVES
RODS
TEMPERATURE EFFECTS
VALVES
WORKING FLUIDS