Abstract: An electropneumatic converter is provided with a voice coil having a vane directly connected to the coil. The vane and coil assembly is attached to a spring and resiliently supported by the spring for movement relative a nozzle outlet in response to dc input signals applied to the coil.

Abstract: An atomizer comprises a cylindrical mixing chamber with open entry and discharge ends. An inner barrel for a slurry or fluidized dry powder is connected to the entry end for supplying the slurry or fluidized fine powder into the mixing chamber. One or more atomizing gas ports extend at an angle into the mixing chamber for supplying atomizing gas to be thoroughly mixed with the slurry or fluidized dry powder in the mixing chamber. The atomizing gas ports are spaced upstream from the discharge end by from one to five times the diameter of the mixing chamber, and downstream from the entry end. A larger diameter volume chamber communicates with the discharge end of the mixing chamber and has at least one nozzle which permits the homogenized mixture to exit therefrom. An impact surface is positioned opposite the discharge end. The at least one nozzle is positioned around the impact surface.

Abstract: An on-line serial communication interface is established from the transmitter of a two line current loop transmitter to a digital circuit such as a computer or hand-held terminal which receives and processes digital voltage pulses. The interface includes a comparator having a positive terminal connected by a capacitor to one of the current lines, and a negative terminal connected to a source of small positive voltage. The output of the comparator is connected to an input port of the digital device. The transmitter modulates the current on the current loop by a small amount with respect to the analog current communicated by the transmitter. This generates voltage pulses in the capacitor which are compared to the selected voltage and are amplified to form large pulses used for communication with the computer or hand-held terminal.

Abstract: A system which utilizes optic fibers for the transmission of light from a process measuring device to an alarm actuating circuit is disclosed. An optic fiber (14) is positioned adjacent each process monitoring location and transmits light therefrom to a remotely located matte screen (12) from which it is reflected to a pair of optic fibers (16, 18). The optic fibers (16, 18) transmit the light of optic diodes (20, 22), respectively, which are selectively actuated in response to the color of the light being transmitted and which, in turn, selectively actuate an alarm circuit connected thereto.

Abstract: A method and apparatus of converting analog voltage signals to digital frequency signals comprises a voltage to frequency converter having an output which produces pulse trains that are proportional to the voltage level of an analog voltage signal applied to the converter. A microprocessor is connected to the converter for sampling the pulse trains during a fixed sampling period. The microprocessor detects the leading edges of the first and last pulse in the pulse train, stores the occurrence time for the two leading edges and then subtracts the occurrence times to calculate the duration time for all the pulses in the sample period between the leading edges of the first and last pulses. A counter counts the number of pulses between the first and last pulse, and a calculation is made dividing the number of pulses by the time duration to yield an accurate measurement of the frequency for the pulse train.

Abstract: A carbon monoxide detector comprises a single monochromatic infrared source which is arranged to alternately direct light through two separate gas-containing test chambers. The first chamber is supplied with gas to be tested which has an unknown carbon monoxide content. A catalytic burning chamber is connected between the first and second chambers to receive gas from the first chamber, burn the carbon monoxide in the gas to carbon dioxide and supply the carbon monoxide free gas to the second chamber. A single infrared light detector is provided for receiving light as it comes alternately from the two chambers. The light from the two chambers is compared to determine the amount of carbon monoxide present in the gas of the first test chamber. Since the same background gas is provided in both chambers and only a single infrared source and detector are utilized, inaccuracies due to differences in background detection, infrared source intensity and infrared detector sensitivity are overcome.

Abstract: A device for sealing and isolating analyzer gas sample flows in an aspirated sampling system is provided with a drainage channel surrounding the gas sample inlet to isolate the inlet in the plane of the sealing surface from a pressurized air supply channel in the sealing surface and intercept leakage from the air supply channel. The drainage channel is connected to a cavity via a constricted flow path to reduce leakage pressure and the cavity is vented to the environment.

Abstract: Steel tubulars are deposited into an insulated container shortly after the steel tubulars are formed in a seamless hot rolling machine. The tubulars are covered by an insulating blanket and allowed to cool at a selected rate to form desired microstructure in the steel of the tubulars. No external energy supply or controls are necessary to achieve the desired microstructure. The side walls of the container taper outwardly and are made of a sandwiched structure, having spaced apart sheet metal members with a layer of insulation there between. The end walls are similarly constructed. The bottom of the container is lined with granular insulating material to cushion the shock of the tubulars being dropped into the container and to insulate the bottom of the container. Stainless steel mesh is used as a sling and embraces the tubulars to facilitate removing the tubulars from the container after the desired amount of cooling.

Abstract: A process of controlling emission of SO.sub.x, NO.sub.x and particulates from a coal-fired boiler system is disclosed. A reagent/catalyst in powdered form is added into the combustion flue gas stream intermediate the boiler and economizer at a temperature below the melting point of the powder. The reagent/catalyst and ammonia are reacted with the SO.sub.x and NO.sub.x while the flue gas passes through the economizer. Further reaction is achieved as the gas is passed through the filter cake which forms on the filterhouse bags.

Abstract: An improved process measurement system is disclosed which provides automatic signal evaluation and transfer in connection with redundant signals generated from a common data source over two input channels and one output channel. The two input channels are monitored by a series of three comparators which compare real time values of the signals on the two channels, and as well, a real time and delay value from each channel.

Abstract: A display system for displaying select dynamic process data of plant operations to an operator providing a display of only dynamic data having a predetermined difference between current and stored values.

Abstract: A dual cantilever beam member for aligning optical fiber cables is disclosed. A first optical fiber cable is received through and attached to one end of the beam member while a second optical fiber cable is received through and attached to the other end of the beam member causing the ends of the optical fiber cables to be in close proximity to one another. The dual cantilever construction of the beam member allows relative displacement of the one optical fiber cable with respect to the other optical fiber cable along only one co-ordinate axis and prevents relative displacement of the optical fiber cables along the other co-ordinate axes. A chord shaped portion on the end of each optical fiber cable is blocked to define the transmission area between the cable ends and to increase displacement sensitivity of the device.

Abstract: A system for controlling steam temperature in a boiler using a time delay feedback controller known as a Smith Predictor to provide control tuning of true boiler parameters which change with load.

Abstract: Coal is immersed in an organic solvent for a sufficient time to induce swelling and natural fracture of the coal. The swelled coal is chemically leached to produce deep cleaned coal fines.

Abstract: A line build out comprises a control voltage mechanism for applying a control voltage to a tuning diode or varactor. The control voltage is generated so as to be indicative of the length of a cable over which the signal has traveled. The capacitance of the tuning diode or varactor is changed according to the control voltage. A resistor is connected to the cathode of the tuning diode or varactor and a capacitor is connected to the anode of the tuning diode or varactor. A signal can be measured at the cathode which corresponds to the incoming signal and has been attenuated by frequency roll-off in accordance with the length of the cable over which the signal has traveled. In this way, attenuation for signals over cables of various length can be equalized in a manner which not only takes into account the length of the cable, but also the frequency of the signal.

Abstract: A method and apparatus for eliminating microfissure defects in shape melted austenitic material components by closely controlling the deposited weld bead shape to a geometry where the underbead shape has no sharp discontinuties. Oscillation of the welding torch head during the process is used to smooth out the weldbead shape and is especially adapted for use with gas metal-arc welding processes.

Abstract: A convertor for converting an analog signal to a digital pulse comprises a switching capacitor which is charged by a differential analog signal supplied to the switching capacitor over an input circuit. The capacitor is discharged over an output circuit with the aid of a constant current supply. The charge level of the capacitor is proportional to the analog signal so that the time it takes the capacitor to discharge to a selected low charge level, is proportional to the analog signal. This time period is used by a microprocessor control to generate a digital pulse having a pulse equal to the discharge time for the capacitor. The microprocessor also selectively connects the input and output circuits to the capacitor for respectively charging and discharging the capacitor.

Abstract: A safety control system for a coal pulverizing mill is disclosed. The control system utilizes measurements of the net oxygen level and the carbon monoxide equivalent (CO.sub.e) level of the combustible gases within the pulverizing mill. First levels of the net oxygen and the rate of carbon monoxide equivalent change in the pulverizing mill are utilized in a control logic system to actuate alarms. Second levels of the net oxygen and the carbon monoxide equivalent (CO.sub.e) level in the pulverizing mill are utilized to accomplish the inerting of the mill.

Abstract: A control system for a heat exchanger, such as a superheater in a fossil fuel fired steam generator, uses a multivariable non-linear regression equation to develop a feed forward signal that continuously adapts itself to changes in system variables to adjust the enthalpy of the steam entering the superheater and maintain a substantially constant enthalpy of the steam discharged from the superheater. The system develops a feedback signal responsive to changes in the temperature of the steam discharged from the superheater to readjust the enthalpy of the steam entering the superheater as required to maintain the steam leaving the superheater at a predetermined set point temperature.

Abstract: A method and apparatus for building an axially symmetrical workpiece of desired geometry by deposit welding which uses a translatable welding head for depositing molten weld material and a rotatable, reusable shoe which translates with the welding head. The rotatable, reusable shoe forms, supports and cools the deposited molten weld material puddle while the weld material is solidifying thereby eliminating the need for a conventional preform.