Abstract: A DC power plant generating DC power from a variety of engines including a Stirling cycle engine. The DC power plant includes a relatively small start-up power source that is discontinued after the engine is running. A method for producing DC power for a load including starting up an engine using power supplied by a relatively small power supply supplemented by a capacitor bank, providing output from the engine to a generator, producing alternating current (AC) power by the generator, converting the AC power to direct current (DC) power, disabling output of the DC power during a first set of pre-selected conditions, limiting a rate of change of current of the DC power during a second set of pre-selected conditions, reducing conducted and radiated emissions of the DC power, disconnecting the DC power from the load under a third set of pre-selected conditions, and providing the DC power to the load.

Abstract: Disclosed are passive reflector radio communications systems, such as for UHF frequencies or greater than UHF frequencies, and related deployment systems and devices that provide underground communications. Embodiments of the system include reflector elements to provide passive radio communications, structural frameworks to support and orient the reflector elements, methods for calculating reflector size, shape, and position corresponding to a desired wavelength, and deployment methods and devices to install the communication system at a desired location. The passive reflectors can be placed in a folded or otherwise compact mode, for transport into underground tunnels. Once at the desired installation location, the system can be installed, with the reflectors positioned appropriately for the radio frequencies used at the location.

Abstract: A transmitter manifold with integral transducer for measuring the differential pressure of a fluid conveying pipeline is provided. Interface modules are provided to provide for adaptability to a variety of user requirements. A sealing arrangement for the interface modules is also provided. In preferred form, the interface module includes a body having a flange portion and a neck portion extending outwardly from the flange portion, with the flange portion including holes for engagement with bolts threaded into the transmitter manifold.

Abstract: A transmitter/manifold with integral transducer for measuring the differential pressure of a fluid conveying pipeline is provided. Valves are arranged to provide automatic sequencing for service functions. Means for heating the transmitter/manifold is provided. Interface modules are provided to provide for adaptability to a variety of user requirements. A sealing arrangement for interface modules is also disclosed.

Abstract: An improved differential pressure transducer is provided having static overpressure protection means. The overpressure protection means includes spring-loaded element being shiftable in response to an overpressure condition.

Abstract: The valve is particularly designed compatible for use with toxic or highly flammable fluids. It has a hard valve stem tip, such as tungsten carbide which is pushed longitudinally against the valve seat and not rotated into sealing position. The valve is provided with a backseat threaded to the valve body so that if the bonnet or packing nut is very seriously abused by the operator even to the extent of twisting or breaking, the valve will not blow out toxic or flammable fluid. Most of the parts of the valve are made of stainless steel and provisions are made for lubricating the working parts of the valve. Notches in the valve stem and packing nut provide for a safe clean break of these parts in the event they are over stressed.

Abstract: A ball check valve connects to a duct leading from a process pipe to a flow transmitter, pressure gauge or sampling analyzer. A unique check valve is connected to the distal end of the straight-through duct. A cleaning rod impales a packing gland which is connected onto the check valve when cleaning is initiated. The cleaning rod is inserted through the check valve and into the duct to clean debris without the loss of any fluid while maintaining full process pressure.

Abstract: A valve connects the duct leading from a process pipe to a flow transmitter, pressure gauge or sampling analyzer. The valve stem of the valve is hollow and aligned with the duct through the connection to process fluid. A cleaning rod is telescoped within the hollow stem so that it may be forced through the duct to clean debris from the duct. Also the valve handle has capstan holes therein for mechanical advantage. Furthermore, a bonnet valve seat is used so that the bonnet packing may be removed while the equipment is pressurized.