Hydraulic double acting valve actuator

A modular hydraulic actuator comprising:

• a first modular actuator portion comprising:
• a hollow cylinder portion,
• a cylinder retainer portion located along an outside surface of the cylinder portion and at a first end of the cylinder portion, the cylinder retainer portion having a plurality of screw holes formed therein,
• a piston located in the cylinder portion, the piston being adapted to slidably fit in the cylinder portion, and the piston having a slotted portion formed therein,
• a cylinder head portion closing a second end of the cylinder portion,
• a locking screw extending through the cylinder head portion and threadedly coupled to the cylinder head portion, the locking screw being adapted to press against the piston with an end of the locking screw to displace the piston, and
• a piston retainer portion located at an interior surface of the cylinder portion and at the first end of the cylinder portion, wherein part of the piston retainer portion extends radially inward relative to the interior surface farther than a portion of the piston such that the piston cannot slide completely past the piston retainer portion;
• and
• a second modular actuator portion comprising:
• a bonnet portion having a central hole formed therethrough, the bonnet portion having a plurality of screw holes formed therein at one end of the bonnet portion, wherein the bonnet portion screw holes correspond to the cylinder retainer portion screw holes,
• an operating stem extending through the bonnet portion central hole, the operating stem having a first end removably coupled to the valve member, and the operating stem having a threaded second end,
• a nut having an exterior shape adapted to slidably interfit with the slotted piston portion, and the nut having a threaded hole formed therein where the nut is threadedly coupled with the threaded second end of the operating stem;
• wherein the first modular actuator portion is removably coupled to the second modular actuator portion with a plurality of fasteners via the cylinder retainer screw holes and the bonnet screw holes;
• and
• wherein the first modular actuator portion can be separated from the second modular actuator portion without disassembling the first modular portion.

A hydraulically actuated valve assembly, comprising:

• a valve component comprising:
• a valve body, the valve body having a plurality of screw holes formed therein, and
• a valve member located in the valve body and that slidably fits in the valve body;
• a modular hydraulic actuator comprising a first modular portion and a second modular portion;
• the first modular actuator portion of the actuator comprising:
• a hollow cylinder portion,
• a cylinder retainer portion located along an outside surface of the cylinder portion and at a first end of the cylinder portion, the cylinder retainer portion having a plurality of screw holes formed therein,
• a piston located in the cylinder portion, the piston being adapted to slidably fit in the cylinder portion, and the piston having a slotted portion formed therein,
• a cylinder head portion closing a second end of the cylinder portion,
• a locking screw extending through the cylinder head portion and threadedly coupled to the cylinder head portion, the locking screw being adapted to press against the piston with an end of the locking screw to displace the piston, and
• a piston retainer portion located at an interior surface of the cylinder portion and at the first end of the cylinder portion, wherein part of the piston retainer portion extends radially inward relative to the interior surface farther than a portion of the piston such that the piston cannot slide completely past the piston retainer portion;
• the second modular actuator portion comprising:
• a bonnet portion having a central hole formed therethrough, the bonnet portion having a first plurality of screw holes formed therein at a first end of the bonnet portion, wherein the first plurality of bonnet portion screw holes corresponds to the cylinder retainer portion screw holes, the bonnet portion also having a second plurality of screw holes formed therein at a second end of the bonnet portion, wherein the second plurality of bonnet portion screw holes corresponds to the valve body screw holes,
• an operating stem extending through the bonnet portion central hole, the operating stem having a first end removably coupled to the valve member, and the operating stem having a threaded second end,
• a nut having an exterior shape adapted to slidably interfit with the slotted piston portion, and the nut having a threaded hole formed therein where the nut is threadedly coupled with the threaded second end of the operating stem;
• wherein the first modular actuator portion is removably coupled to the second modular actuator portion with a first plurality of fasteners via the cylinder retainer screw holes and the first bonnet screw holes;
• wherein the first modular actuator portion can be separated from the second modular actuator portion without disassembling the first modular portion;
• and
• wherein the second modular actuator portion is removably coupled to the valve body with a second plurality of fasteners via the second bonnet screw holes and the valve body screw holes.

A method of disassembling a modular actuator component for accessing at least one seal in the modular actuator component, comprising the steps of:

• loosening a plurality of fasteners that hold a first modular portion of the actuator component and a second modular portion of the actuator component together;
• wherein the first modular actuator portion comprises:
• a hollow cylinder portion,
• a piston located in the cylinder portion, the piston being adapted to slidably fit in the cylinder portion, and the piston having a slotted portion formed therein,
• a piston retainer portion located at an interior surface of the cylinder portion and at a first end of the cylinder portion, wherein part of the piston retainer portion extends radially inward relative to the interior surface farther than a portion of the piston such that the piston cannot slide completely past the piston retainer portion,
• a cylinder head portion closing a second end of the cylinder portion, and
• a locking screw extending through the cylinder head portion and threadedly coupled to the cylinder head portion, the locking screw being adapted to press against the piston with a first end of the locking screw for displacing the piston;
• and
• wherein the second modular actuator portion comprises:
• a bonnet portion having a central hole formed therethrough,
• an operating stem extending through the bonnet portion central hole, the operating stem having a threaded end,
• a nut having an exterior shape that is slidably engaged with the slotted piston portion, and the nut having a threaded hole formed therein that threadedly interfits with the threaded operating stem end, and
• the at least one seal located about the operating stem;
• displacing the piston towards the first end of the first modular portion until the slotted piston portion extends outside of the first modular portion;
• preventing the piston from being completely slid out of the first modular portion through the first end of the cylinder portion with the piston retainer portion;
• sliding the nut out of engagement with the slotted piston portion;
• and
• separating the first modular portion from the second modular portion.