Abstract: A pressure switch has a housing with an interior bore extending from one end to the other. A rod slidable within the bore and operated by external fluid pressure extends between a piston at one end of the housing and a mechanically operated electrical switch at the other end of the housing. A spring is disposed about the rod between a first stop on the rod and a second stop on the housing. The spring provides resistance against movement of the rod under external pressure. The resistance of the spring to movement is adjusted by a sleeve engaging the spring, with the sleeve threaded into the bore of the housing for movement longitudinally within the housing. The sleeve includes plural radially extending slots disposed around the sleeve. A port in the housing allows access to the sleeve and a cover is provided for the port. The cover includes a ring disposed around the housing and threaded onto the housing over the port.

Abstract: A pressure responsive pilot control valve has a spool which is movable by a metal diaphragm sensing the pressure in a flowline. The spool includes two poppet seal rings mounted thereon, the poppet seal rings having concentric axes and which are used for opening and closing fluid ports. The fluid ports are opened and closed for the purpose of sending a signal to a latching relay valve to bleed off a shut in valve actuator which will terminate flow in the flowline. The poppet seal rings of the pilot move responsive to a high or a low pressure condition. A low pressure spring is provided for measuring a low pressure condition and a high pressure spring is provided for measuring a high pressure condition.

Abstract: A latching trip valve for opening and closing a safety device. The trip valve is operable manually and from the pressure of a pilot circuit which monitors the operating conditions of a pipeline. A floating seat is movable under the influence of a longitudinal movable poppet and its included seal means. The floating seat and seal means forms a closed passage until the pressure of the pilot circuit decreases whereas the passage is opened.

Abstract: An emergency shut down device for a gate valve utilizes a pre-assembled spring cartridge assembly which includes a container and a compression spring pre-loaded therein. Suitable openings are provided in the end plates of the cartridge to permit the remaining components, including a ram cup, a piston and cylinder arrangement, a base mounting member and a stem for connection to the valve gate, to be assembled within the cartridge without fear of a spring-initiated explosion of parts as the spring is safely contained within the container before final assembly begins. The device is operable to rapidly close a gate valve when there is a loss of fluid pressure within the device.

Abstract: A sampling device for sampling fluids such as those carried in an oil pipeline comprises two valve means and a sampling chamber located on the fluid passageway in the sampler housing. Fluid is admitted to the probe of the sampling device when the first valve means allows the passageway to be opened and the fluid is admitted or drawn into the sampling chamber. After the first valve means is closed, the second valve means is opened and the fluid exits from the sampling chamber under the action of the plunger. Provision is made to easily clean the buildup of deposits in the fluid passageway without disassembly of the sampling device.