Abstract: An improved main shaft for a coal pulverizer having a selected portion of the main shaft provided with an intervening material such as a thermally sprayed ceramic coating.

Abstract: An EMAT apparatus which non-destructively tests spot welds between two sheets of metal. The apparatus includes a first EMAT coil on one sheet that acts as a transmitter for generating and transmitting an acoustic wave signal toward the spot weld, and a second EMAT coil on the other sheet for receiving the acoustic wave signal and converting the received acoustic wave signal to an electronic signal having a waveform. Electronics and a PC are used to measure at least one parameter of the waveform which is indicative of a characteristic of the spot weld.

Abstract: A heat pipe has an elliptical cross-section. Heat exchange fins are mounted to the heat pipe at the condenser end. The fins are galvanized on the heat pipe. Spacer pins can be used to support and space the heat exchange fins from each other. Internal spacers can be provided within the heat pipe to add support to the heat pipe structure for longer heat pipes.

Abstract: A composition which is densifiable at low temperatures in an air atmosphere suitable for use as an interconnect layer in a solid oxide fuel cell. Binary alloying of SrO and CaO with LaCrO3 is used to form a compound having the general formula La(1−x)(Sr,Ca)xCrO3 which is a stabilized form of LaCrO3 and has the desirable properties for a fuel cell interconnect layer.

Abstract: Ceramic composites containing weak interfacial boundaries included for the purposes of providing avenues for crack deflection with a resulting toughening of a ceramic body. Weak interfacial boundaries are created between constituents of the composite, such as matrix phases and any continuous and/or particulate reinforcements, and tungstate, molybdate, tantalate, and niobate compounds of the general formula ABO4. For tungstate and molybdate compounds of the general formula ABO4, B represents tungsten or molybdenum, and A represents a divalent cation. For tantalate and niobate compounds of the general formula ABO4, B represents tantalum or niobium, and A represents a trivalent lanthanide series cation. The ABO4 tungstate, molybdate, tantalate, and niobate compounds may exist as barrier phases between the matrix and the reinforcements of the composite, or the ceramic body may contain discrete particulates, laminae, fibers, or whiskers of the ABO4 tungstate, molybdate, tantalate, and niobate compounds.

Abstract: A diaphragm weld assembly for preventing fluid leakage from a flange. The diaphragm weld assembly has a flange having a platform, the platform having an opening and an annular weld pocket concentric with the opening, a diaphragm resting on the platform and having a ring extending from the bottom face of the diaphragm, the ring engaging with the opening, a weld bead formed in the annular weld pocket and welding the diaphragm to the flange, and a flange cover fastened to the flange. A method of creating the diaphragm weld assembly is also provided.

Abstract: A method for improving the corrosion resistance, increasing the hardness, providing superior ductility, and reducing surface-cracking of a diffusion coating by nitriding and heating-treating the diffusion coating is disclosed. The nitriding and heat-treating may occur subsequently or simultaneously. Further, the disclosed method may be practiced subsequent to or incorporated as an intergral part of any known diffusion coating process which utilizes a heating step in a furnace having a cover gas.

Abstract: A transmitting and receiving switch assembly for an electromagnetic acoustic transducer (EMAT) and a method for selectively switching an EMAT between transmit mode and receive mode both use a particular circuit. This circuit contains an EMAT coil coupled to a tuning capacitor, which allows the EMAT to be operated at a desired frequency when transmitting. A set of capacitors separates the EMAT coil from a set of diode strings (preferably containing at least one fast switching silicon diode), which are joined by a resistive connection. A transformer, which is center tapped at its primary winding, is coupled to the other end of the diode strings. Finally, a receiver input is connected to the transformer. In operation, the frequency of the EMAT is set by appropriately energizing and tuning the tuning capacitor. A voltage is then applied in the center tapped transformer and in the resistive link between the diode strings.

Abstract: A turret system is installed on an existing vessel such as an oil tanker. A portion of the existing structure, such as the center splice, is removed to leave an opening. A support structure is attached within the opening. The support structure includes a turret support structure. The turret structure is assembled within the turret support structure. Fluid piping is installed between the turret structure and the pipework of the vessel, including a manifold structure and a fluid swivel. The turret assembly is cladded for environmental protection. In one arrangement, the turret system is within the profile of the original vessel. In another arrangement, the turret system is external to the profile of the original vessel.

Abstract: An ultrasonic method for determining liquid level in a container employs an electromagnetic acoustic transducer (EMAT) to launch and receive longitudinal ultrasonic waves into a thin metal wall or thin metal foil seal of the container, causing it to vibrate and launch ultrasonic compressional waves into liquid contained therein. The compressional waves travel through the liquid contents and reflect off an interface, returning to the thin metal wall and causing it to vibrate in the presence of the magnetic field produced by the EMAT transducer assembly. This induces a voltage in the eddy current coil of the EMAT transducer assembly, and by measuring a time of flight of the ultrasonic compressional waves through the liquid contents, and by using a preestablished value for a velocity of the ultrasonic compressional waves within the liquid contents, the liquid level of the contents can be determined.

Abstract: An EMAT testing device for nondestructively testing tubes for surface defects and displaying the results has a EMAT transmitter arranged collinear with a pair of EMAT receivers. The EMAT receivers each receive a pair of oppositely propagating circumferential acoustic surface waves from the transmitter at different times and the relative amplitudes of the received waves are compared to located defects adjacent the receivers in the tube.

Abstract: A method for inspecting welds uses a single EMAT tranducer operated in pulse-echo mode that sends and receives Rayleigh waves to detect defects in a weld between sheet plates of dissimilar thicknesses.

Abstract: A method for detecting the location of an edge, interface, seam or other structure of a workpiece uses one or two electromagnetic acoustic transducers (EMATs) to transmit an ultrasonic wave along the workpiece toward the edge and to receive a reflected wave. The velocity of the wave in the material is used in conjunction with the round trip time-of-flight (TOF) of the transmitted and reflected wave, to calculate the location of the edge. This is done by placing the transducer or transducers at known locations on the workpiece. A surface wave or 90 degree shear wave can be utilized and no contact is needed between the transducer and the surface of the workpiece. Rough and/or dirty surfaces and hostile environments can be accommodated while practicing the invention.

Abstract: A method and system for removing SO.sub.3 and SO.sub.2 a flue gas produced by the burning of a fossil fuel. Particulates are removed from the flue gas to produce partially cleaned flue gas. A sufficient amount of calcium-based, sodium based or magnesium-based dry sorbent, preferably having a particle size larger than 1.0-2.0 microns, is injected into the flue gas to react with and remove substantially all of the SO.sub.3 from the partially cleaned flue gas to produce a substantially SO.sub.3 -free flue gas containing reacted and unreacted dry sorbent. The substantially SO.sub.3 -free flue gas is conveyed to wet scrubber means for removing SO.sub.2 to produce cleaned flue gas. In a first embodiment, sufficient dry sorbent is provided to remove desired amounts of SO.sub.3 and SO.sub.2. In a second embodiment, a make-up reagent provided to the wet scrubber means wets the dry sorbent, removes both the reacted and unreacted dry sorbent from the substantially SO.sub.

Abstract: A method of detecting damage in a ferromagnetic workpiece such as a boiler tube positions a pair of EMAT coils adjacent to the workpiece at a non-zero angle with respect to one another. A spike pulse is applied to one of the EMAT coils for generating a horizontally polarized shear wave in the workpiece which is capable of being reflected by a flaw, and the amplitude of a reflected wave from any flaw is received at the other EMAT coil and analyzed and compared to a predetermined percent of an amplitude of a calibration standard flaw to establish the presence of the flaw.

Abstract: An EMAT arrangement utilizes separate transmitter and receiver EMATs which may each be connected to a tuning capacitor by a stripline cable. An electrostatic shield may also be provided between the coils and the coils can be offset from each other by 1/2 the pitch distance of sections in the coil. This reduces the duration of main bang, thus making it possible for the EMAT arrangement to detect structures which are very close to the coils.

Abstract: A high performance electrocatalyst is based on transition metal perovskites of praseodymium, samarium, terbium or neodymium which react with YSZ to form a product which is itself active as the cathode in a fuel cell. While PrCoO.sub.3 reacts with YSZ, the reaction product(s) do not result in severe degradation of cell performance. A fuel cell made with a cathode composed of only the reaction product of YSZ and PrCoO.sub.3 has good performance, indicating that this phase is itself not only a good conductor, but also a good catalyst for oxygen activation.

Abstract: A seal joint is for an arrangement for separating a gas and liquid mixture having a vessel with an inlet for entry of the gas and liquid mixture and an outlet for exit of a separated gas, and a centrifugal separation cyclone in the vessel for centrifugally separating the gas from the mixture. The joint requires the vessel to have an internal vessel flange defining a flange opening. An inlet tube extends into the flange opening. A first retaining ring having a first outer ring which engages the flange, also has a first inner ring portion extending around the inlet tube in the flange opening. A second retaining ring has a second outer ring engaged with the flange and a second inner ring extending around the inlet tube in the flange opening. An O-ring is engaged around the inlet tube and between the first and second inner rings and fastening bolts are use for fastening the first and second outer rings to the flange, around the flange opening for deforming the O-ring against the inlet tube.

Abstract: A method and apparatus for filtering oxidizable particles from hot synthesis gas or syngas uses a pair of candle filters each having an inlet side for receiving the hot unfiltered syngas to be filtered, and an outlet side for discharging hot filtered syngas. One housing contains both filters or a separate housing is provided for each filter. Each housing has an inlet for receiving hot unfiltered syngas and for supplying the hot unfiltered syngas to each of the filter inlet sides. Each housing also has an outlet for discharging hot filtered syngas from each of the filter outlet sides. Air is supplied to each housing for supplying combustion air alternately to each of the candle filters for burning oxidizable particles trapped on each respective filter to clean each filter while the other filter is filtering the hot unfiltered syngas. One or more switching valves are connected to the combustion air supplies for alternating the supply of combustion air between the candle filters.

Abstract: A circulating fluidized bed (CFB) reactor or combustor having an internal impact type primary particle separator which provides for internal return of all primary collected solids to a bottom portion of the reactor or combustor for subsequent recirculation without external and internal recycle conduits. The CFB reactor enclosure or furnace is provided with plural furnace outlets. This construction permits increased furnace depths and reduced furnace widths, resulting in a compact design.