Reversed actuator with minimal leak potential

A valve assembly, comprising:

• a valve body having an inlet port, an outlet port, and a flow passage therebetween;
• a valve element movably disposed within the valve body flow passage;
• and
• an actuator assembly configured to move the valve element, the actuator assembly comprising:
• an actuator housing;
• a piston disposed within the actuator housing, the piston configured to couple to the valve element and including an inner cylindrical section and an outer cylindrical section, the outer cylindrical section spaced apart from the inner cylindrical section to define a recess, the piston further configured to move within the actuator housing in a first direction and a second direction, to thereby move the valve element toward an open position and a closed position, respectively, the piston including a first side at least partially defining a pressurized closing chamber and a second side at least partially defining a pressurized opening chamber;
• a regulator coupled between the pressurized closing chamber and the pressurized opening chamber and configured to regulate pressure in the pressurized opening chamber by bleeding off air;
• a dynamic seal in series with the regulator and disposed between the pressurized closing chamber and the actuator housing;
• and
• a spring disposed within the actuator housing and configured to supply a bias force that urges the piston to move in the first direction, the spring at least partially disposed within the recess and at least partially surrounding the inner cylindrical section.

A valve actuator assembly, comprising:

• an actuator housing;
• an actuator housing cover at least partially surrounding the actuator housing;
• a piston, having a first side and a second side, the piston disposed within the actuator housing, the piston configured to couple to a valve element and including an inner cylindrical section and an outer cylindrical section, the outer cylindrical section spaced apart from the inner cylindrical section to define a recess, the piston further configured to move within the actuator housing in a first direction and a second direction, to thereby move the valve element toward an open position and a closed position, respectively, and wherein the piston defines a pressurized closing chamber between the piston first side and the actuator housing and a pressurized opening chamber between the piston side and the actuator cover, the pressurized closing chamber and the pressurized opening chamber having respective pressure levels that are each greater than a pressure level surrounding the actuator housing;
• a regulator coupled between the pressurized closing chamber and the pressurized opening chamber and configured to regulate pressure in the pressurized opening chamber by bleeding off air;
• and
• a spring disposed within the actuator housing and configured to supply a bias force that urges the piston to move in the first direction, the spring at least partially disposed within the recess and at least partially surrounding the inner cylindrical section.