Abstract: An electro-pneumatic controller adapted to use a non-inert fluid as a control fluid includes a base portion and a cap portion removeably secured to the base portion. A non-intrinsically-safe process may be disposed within an interior of the cap portion. A plurality of passageways may be disposed through the base portion. The electro-pneumatic controller may also include a flameproof barrier assembly which may include a plurality of flameproof joints each disposed within desired portion of the plurality of passageways. The plurality of flameproof joints cooperate to at least partially define a first zone, the flameproof joints adapted to prevent or to limit the spread of an open fire or explosion that might occur due to the ignition of the non-inert control fluid.

Abstract: A flame arrestor assembly configured to extinguish a flame propagating between a process control device and a combustible environment outside the process control device. The flame arrestor assembly includes a flame arrestor and a retaining element. The flame arrestor has a body adapted to be disposed within a fluid flow passageway of the process control device. The retaining element is adapted to be disposed within the fluid flow passageway of the process control device proximate to the flame arrestor, and is configured to securely retain the flame arrestor within the fluid flow passageway of the process control device.

Abstract: A tool for inserting a flame arrestor assembly into a process control device having a first passageway of a first depth and a second passageway of a second depth different from the first depth. The tool includes a head portion having a first diameter, and a tip portion having a second diameter less than the first diameter. The tip portion has a first portion, a second portion, and a third portion, the first and second portions being separated by a first notch, and the second and third portions being separated by a second notch. The first notch is arranged to indicate when the flame arrestor assembly is fully inserted into the first passageway, and the second notch is arranged to indicate when the flame arrestor assembly is fully inserted into the second passageway.

Abstract: An electro-pneumatic controller for use with a regulator. The electro-pneumatic controller includes a base having a body, a top surface, and a bore formed within the body. A locking mechanism is disposed within the bore of the body of the base, the locking mechanism having a top surface flush with the top surface of the base. A cover is coupled to the base and includes an open end with a rim, the rim contacting the top surface of the base and a portion of the top surface of the locking mechanism. The locking mechanism is rotated via a tool in a counter-clockwise direction after the cover contacts a portion of the top surface of the locking mechanism to lock the cover to the base.

Abstract: An electro-pneumatic controller includes a base portion having at least one lateral surface and a plurality of passageways disposed through the base portion. A bore extends through the lateral surface, and the bore has a counterbore portion and a threaded engagement portion. A standard NPT plug may be coupled to the base portion, and the plug has a head portion and an engagement portion that threadedly engages the engagement portion of the bore. A top surface of the head portion of the plug is coplanar with the lateral surface of the base portion or is disposed within the counterbore portion of the bore.