Abstract: A fiber optic acoustic emission (FOAE) sensor particularly suitable for vibration sensing in a hostile environment has a pair of optical fibers each having an end face. In one embodiment, a hollow tube or core having opposite open ends receives the end faces of the optical fibers. Means are provided for fixing the optical fibers in the hollow core with the end faces facing each other and spaced by a distance from each other in the core. A signal processing unit is connected to the optical fibers for supplying light to, and for receiving light from, the optical fibers and for measuring variations in optical phase which result in changes in the light intensity due to vibrations of the hollow core. The hollow core is fixed in a resonant cylinder, and the resonant cylinder is fixed in a housing to complete the sensor.

Abstract: An improved plasma arc welding arm method and apparatus for keyhole welding rotating workpieces has an arcuate gear track supporting a corresponding arcuate geared cart bearing a plasma arc welding torch prevents voids in keyhole weld starts and finishes. The gear track is mounted on a manipulator arm for positioning the welding torch in proximity to a rotating workpiece to be welded. The torch may be rotated on the cart and gear track in the same direction and at the same rotational speed as the workpiece.

Abstract: An on-line X-ray fluorescent monitoring system uses a probe having an X-ray transmitter and a fluorescent X-ray detector placed adjacent a recessed chamber in a coal feed line having an X-ray transparent window. Pulverized coal traveling through the coal feed line collects in the recessed chamber and rests against the X-ray transparent window where it is bombarded by excitation X-rays from the transmitter. The probe receives fluorescence from the X-ray excited coal and transmits the data to a data acquisition and control means for analysis and use. A pressurized air tube is provided at the base of the recessed chamber for blowing accumulated pulverized coal out of the recessed chamber and back into the feed line, thereby allowing a new sample portion of pulverized coal to settle into the recessed chamber for analysis. The on-line analyzer can also be used to determine concentrations of other elements of interest in the pulverized coal, such as iron, chlorine, etc.

Abstract: A combined furnace limestone injection and dry scrubber flue gas desulfurization (FGD) system collects solids from the flue gas stream in first particulate collection device located downstream of an outlet of a convection pass of the furnace and upstream of the dry scrubber. The collected solids are diverted to the dry scrubber feed slurry preparation system to increase sulfur oxide species removal efficiency and sorbent utilization. The level of lime in the feed slurry provided to the dry scrubber is thus increased, which enhances removal of sulfur oxide species in the dry scrubber. The decreased particulate loading to the dry scrubber helps maintain a desired degree of free moisture in the flue gas stream entering the dry scrubber, which enhances sulfur oxide species removal both in the dry scrubber and downstream particulate collector, normally a baghouse.

Abstract: An air premixed natural gas burner having reduced thermal and prompt NO.sub.x emissions employs a central, cylindrical core chamber and an outer annular chamber separated by a hollow barrel having a plurality of gas spuds at a front end of the burner adjacent to a burner throat. The plurality of gas spuds introduces natural gas into a core chamber air flow passing through a fixed swirler and controlled by a sliding air flow damper associated with the central, cylindrical core chamber. A reduced air/fuel stoichiometric ratio (of approximately 0.6) is preferably maintained at an outlet of the central, cylindrical core chamber. The balance of the combustion air is provided through the outer annular chamber to maintain an overall or cumulative burner stoichiometric ratio of approximately 1.05.

Abstract: A drainable discharge pan apparatus for an impact type particle separator used on circulating fluidized bed (CFB) boilers employs a plurality of funnel shaped discharge pans located at a lower end of each of the impingement members in the impact type particle separator. The funnel shaped discharge pans prevent accumulation of collected particles thereon, allowing particles collected by the impingement members to fall therethrough, while preventing bypassing of flue gas around lower ends of the impact type particle separator. The outlet ends of the funnel shaped discharge pans provide substantially the same open area for the collected particles to fall therethrough as exists within each associated impingement member.

Abstract: A combined furnace limestone injection and dry scrubber flue gas desulfurization (FGD) system collects solids from the flue gas stream in first particulate collection device located downstream of an outlet of a convection pass of the furnace and upstream of the dry scrubber. The collected solids are diverted to the dry scrubber feed slurry preparation system to increase sulfur oxide species removal efficiency and sorbent utilization. The level of lime in the feed slurry provided to the dry scrubber is thus increased, which enhances removal of sulfur oxide species in the dry scrubber. The decreased particulate loading to the dry scrubber helps maintain a desired degree of free moisture in the flue gas stream entering the dry scrubber, which enhances sulfur oxide species removal both in the dry scrubber and downstream particulate collector, normally a baghouse.

Abstract: A scintillating optical fiber sensitive to low energy radiation has a clear, solid, elongated core with a thin cladding layer surrounding substantially all of the core along substantially all the length of the core and a dye dopant dispersed within the thin cladding layer. When a low energy radiation particle contacts the thin cladding layer, energy from the particle is transferred to photons having a radiant energy frequency determined by the dye dopant color, and a fraction of the photons are transmitted through the fiber by total internal reflection. A detector using the scintillating optical fiber is also disclosed having a sensor for detecting and indicating the presence of photons operatively connected to an end of at least one optical fiber, such that when the fraction of photons are transmitted through the fiber by total internal reflection to the end, the sensor detects the photons and subsequently provides an indication that low energy radiation has been detected.

Abstract: An asymmetrical, or non-uniform arrangement of heat exchanging tubes in a second stage heat exchanger of an integrated flue gas treatment system provides improved flow characteristics and reduces or eliminates flooding caused by the counter-flow of upwardly rising flue gases and downwardly falling reagent and condensate through the heat exchanging tubes. The non-uniform spacing produces a non-uniform velocity profile with at least one low velocity region in each row, allowing reagent and condensate to drain downward at said low velocity region, thereby preventing high gas phase pressure drop caused by the onset of flooding. Embodiments are provided in which one of every six tubes are removed from each row in a uniform array of tubes, or one of every four tubes are removed from each row in a uniform array of tubes. Other asymmetrical, or non-uniform spacings are possible.

Abstract: A shim for improving plasma arc weld quality has ends tapered at about 25.degree. and notches at each end roughly centered over the corner between the tapered ends and main body of the shim. The improved shim allows lower starting plasma arc heat input and reduces the occurrence of sagging, or overpenetration, of the weld.

Abstract: A sootblower system for a furnace combustion zone has two types of blower pipes. A first type is made of a high temperature resistant material, and projects a short distance vertically through the floor of the furnace into the combustion zone and has blower orifices substantially parallel to the floor. The second type of blower pipe is made of conventional metallurgical materials and the blower outlet is positioned between and extends through adjacent tubes in a membrane wall at a location proximate the furnace floor. Both types of blowers are stationary and continuously remain in position, inserted in the combustion zone. Both types are small in size and large in number and only a small number of blowers are active at any time. In operation, discrete puffs of blowing medium are forced through the blower pipes and across the furnace floor, entraining ash and particulates into the combustion gas stream, preventing small amounts of ash buildup within the furnace.

Abstract: An apparatus for detecting a leak in the storage tank which includes a transducer for detecting and converting a mechanical wave into an electrical signal, a support tube having an upper end extending outside of the tank and a lower end extending inside the tank into the fluid medium. The transducer is affixed to the lower end of the support tube. A signal processing unit for processing the electrical signal, and electrical cable for transmitting the electrical signal from the transducer to the signal processing unit is also present. A method of using the apparatus is also provided.

Abstract: A method of electromagnetically measuring the distance between adjacent tube elements in a heat exchanger. A cylindrical, high magnetic permeability ferrite slug is placed in the tube adjacent the spacing to be measured. A bobbin or annular coil type probe operated in the absolute mode is inserted into a second tube adjacent the spacing to be measured. From prior calibrations on the response of the eddy current coil, the signals from the coil, when sensing the presence of the ferrite slug, are used to determine the spacing between the tubes.

Abstract: An automated process for inspecting and controlling the quality of titanium welds using color recognition. A color sensor and white light source are mounted to a fixture. The fixture is used to traverse the weld or the part being welded is moved in the viewing path of the sensor. The sensor is calibrated to indicate the desired or undesired color of a weld. A recording device such as a computer is used to receive signals from the sensor and record the location of weld colors that indicate an unacceptable weld. Weld parameters are controlled by color feedback to minimize the deposition of unacceptable weld.

Abstract: A variable power source is provided having multiple power modules each of which can produce a portion of the total range of voltage required for pulsed operation of an electromagnetic acoustic transducer electromagnet. The power modules are connected in series, and controlled by individual potentiometers which are simultaneously adjusted. Selector switches are provided for enabling or disabling each module. The output of the power modules is connected to a pulser/controller for wave forming prior to sending the output signal to the electromagnet. A noise filter can be placed between the power modules and the pulser. LED-type indicators on the selector switches may be used to indicate the operational status of the modules.