Abstract: A device for measuring the viscosity of a fluid includes a viscosensitive unit through which the fluid flows under laminar flow conditions, a first turbulent flow flowmeter in series with the viscosensitive unit, and a second turbulent flow flowmeter shunting at least the viscosensitive unit. The flowmeters are adapted to determine the head loss .DELTA.p and the flowrate q of the fluid through the viscosensitive unit, the dynamic viscosity .mu. being given by the equation .mu.=.DELTA.p/kq where k is a constant dependent on the viscosensitive unit. The device is applicable to accurate measurement of fluid volumes.

Abstract: An apparatus detects an opening in a fluid flow passageway such as occurs when a resistance welding cap which is cooled by the fluid flow becomes accidently detached from a welding machine. Upon detection of an opening, an air-actuated pinch lever is activated to quickly pinch shut flexible fluid inlet and outlet hoses and thereby shut off the fluid flow. Inlet and outlet flow rate sensors provide periodic outputs to a digital computer which determines directions of inlet and outlet flow acceleration. If either the inlet or outlet acceleration changes direction, a baseline inlet or outlet flow rate is set equal to the corresponding current flow rate value to prevent erroneous opening detection due to normal flow fluctuations. If the inlet and outlet accelerations are in the same direction, the baseline values are similarly updated. If the inlet acceleration is positive and the outlet acceleration is negative, it indicates a probable opening.

Abstract: In an automated welding machine, where a flow of liquid coolant is supplied to welding components on the machine from a source of coolant and then returned to the source of coolant, a safety system is provided that shuts down the flow of coolant in the event of a fault. Faults are detected by a supply sensor and a return sensor for measuring the flow rates of coolant in the supply and return lines. A microprocessor is adapted to compare the supply flow rate and return flow rate and detect differences between the two rates. The difference between the detected rates as compared to a leak threshold value, and the microprocessor is adapted to generate a valve shutoff signal in the event the detected difference in flow rates exceeds the leak threshold value. A value in the supply coolant line is responsive to the valve shutoff signal to shutoff flow of coolant in response thereto.

Abstract: An apparatus detects an opening in a fluid flow passageway such as occurs when a resistance welding cap which is cooled by the fluid flow becomes accidently detached from a welding machine. Upon detection of an opening, an air-actuated pinch lever is activated to quickly pinch shut flexible fluid inlet and outlet hoses and thereby shut off the fluid flow. Inlet and outlet flow rate sensors provide periodic outputs to a digital computer which determines directions of inlet and outlet flow acceleration. If either the inlet or outlet acceleration changes direction, a baseline inlet or outlet flow rate is set equal to the corresponding current flow rate value to prevent erroneous opening detection due to normal flow fluctuations. If the inlet and outlet accelerations are in the same direction, the baseline values are similarly updated. If the inlet acceleration is positive and the outlet acceleration is negative, it indicates a probable opening.

Abstract: In an automated welding machine, where a flow of liquid coolant is supplied to welding components on the machine from a source of coolant and then returned to the source of coolant, a safety system is provided that shuts down the flow of coolant in the event of a fault. Faults are detected by a supply sensor and a return sensor for measuring the flow rates of coolant in the supply and return lines. A microprocessor is adapted to compare the supply flow rate and return flow rate and detect differences between the two rates. The difference between the detected rates as compared to a leak threshold value, and the microprocessor is adapted to generate a valve shutoff signal in the event the detected difference in flow rates exceeds the leak threshold value. A valve in the supply coolant line is responsive to the valve shutoff signal to shutoff flow of coolant in response thereto.

Abstract: A pneumatic system for comparing air flow characteristics of different unknown flow restrictions. The first head or piece of equipment and a base orifice are installed in turn on the flowbench and air flow rates are measured for each using a critical flow venturi nozzle. The base orifice flow rate is referred to as p.sub.1. The first head or piece of equipment flow rate is referred to as p.sub.2. A small orifice is identified which equates in flow rate to the first head or piece of equipment, p=p.sub.2. A flow coefficient can be calculated were R.sub.1 =p.sub.2 /p.sub.1. A second head or piece of equipment, for comparison, is then flow tested at the same location or at another location under different atmospheric conditions. The ratio of the first condition flow rates p.sub.2 /p.sub.1 multiplied by the base orifice flow rate at condition two, p.sub.3, allows calculation of a theoretical flow rate for the first small orifice (or first head or piece of equipment) at condition two, p.sub.4.

Abstract: A system for monitoring the flow rate of particulate material entrained within an air stream includes a feed hopper providng a source of the particulate material, and a hose for conveying the particulate material within the air stream. A pump draws the particulate material from the feed hopper and transports the particulate material with the air stream through the hose. A flow meter is associated with the hose and measures the mass flow rate of the particulate material through the hose to provide a first flow indication. A device is associated with the feed hopper and measures the change in weight of the feed hopper over a predetermined interval to provide a second flow indication. A controller corrects the first flow indication from the flow meter according to the second flow indication from the gravimetric device.

Abstract: The flow of a liquid reagent gas into a vapor deposition process chamber is adjusted in response to control information provided by a process controller. The controller executes a prescribed mathematical algorithm which utilizes first and second steady-state pressure differentials. The first pressure differential is measured during the flowing of a carrier gas into the chamber. The second pressure differential is measured after the release of the liquid reagent into the chamber.

Abstract: Methods and an apparatus for measuring gas flow with greater reliability than earlier single-rotor and double-rotor turbine meters and dual turbine meter systems are disclosed. The apparatus comprises two independent rotors, in close proximity of each other, housed in the same meter body, but isolated from the effects of each other. No pressure and temperature correction are needed for accuracy performance comparison between the two rotors. Because of the two rotor averaging technique, the reliability of the volume totalization is greatly improved over earlier double-rotor and single-rotor designs.

Abstract: An apparatus and method for automatically determining the measurement accuracy of an uncalibrated field fluid flow meter by comparing its fluid flow volume, measurement, V.sub.f, to a fluid flow volume measurement, V.sub.m, of a master meter of known accuracy. The apparatus comprises fluid flow device operably coupled to the field and master meters for passing a common fluid stream through each of the meters at a predetermined flow rate until a predetermined volume of fluid has been registered by the field meter; a first measurement signalling device for a generating data representing the fluid volume registered by each of the meters; a second signalling device for generating data representing input temperatures and pressures to each of the meters; and a computer coupled to the fluid flow device for automatically controlling the flow rate and calculating the accuracy of the field meter.

Abstract: A computer-controlled method and expert system for urinary flow measurement, analysis and classification that facilitates accurate and reliable discrimination between normal and abnormal micturition. A diagnostic uroflow classification software routine is provided to facilitate reliable interpretation of urinary flow curves. The routine affords a reliable approach to interpret the uroflow curve by characterizing it by reliable and sensitive variables. It can then be determined if the values of these variables lie in the normal range or not. The classification system and method uses diagnostically significant variables with unambiguous definitions, reliable normal limits, and a standardized analysis procedure.

Abstract: In a fluidic flowmeter for measuring the flowrate higher than the preset flowrate by use of a fluidic element and for measuring the flowrate lower than the present flowrate by use of a flow sensor inserted into the nozzle portion, the present invention relates to the fluidic flowmeter that has an abnormality judging circuit for judging an abnormality and issuing a warning signal and also zero point and gain correcting circuits when operating the flowrate on the basis for the signal being output from the flow sensor in the case that the flowrate signal higher than the preset flowrate is to be input only from the flow sensor side and in the case that the flowrate signal higher than the preset flowrate is to be input only from the flow sensor side and in the event that the flowrate signal lower than the preset flowrate is to be input only from the fluidic element side.

Abstract: A method and apparatus for monitoring in real time the mass and energy flow rate of a gas through a pipeline. The invention determines the ratio of the mass flow rate of pipeline gas flowing through a pipeline compared to the mass flow rate of sample gas tapped from the pipeline line. The invention involves tapping sample gas from the pipeline and flowing the sample gas to a capillary tube or a similar device for creating a pressure differential in a small flow. The sample gas is maintained at substantially the same temperature as the gas in the pipeline while the sample gas is in the capillary tube. The sample gas flows through the capillary tube continuously as controlled by a flow controller at a rate that is independent of the pipeline gas flow rate. A differential pressure cell measures the pressure differential of the sample gas across the capillary tube and also measures the pressure differential of the pipeline gas across an orifice in the pipeline.

Abstract: The present invention is a method and apparatus for monitoring in real time the mass and energy flow rate of a gas through a pipeline. The invention determines the mass flow ratio of a pipeline gas flowing through a pipeline compared to sample gas tapped from the pipeline line when the volumetric flow of pipeline gas through the pipeline is measured by a linear flow meter. Sample gas tapped from the pipeline is flowed to a chamber having a section with a fixed volume until the pressure in the chamber section is substantially equal to the pipeline gas pressure. The sample gas is maintained at substantially the same temperature as the gas in the pipeline while the sample gas is in the chamber section. A timer measures the time interval for the sample gas to flow from the chamber section at a selected rate for a calculated pressure drop the selected rate being controlled by a flow controller. The mass flow ratio is computed using the measured time interval and a signal from the linear flow meter.

Abstract: A method for providing improved measurement of oil, water, and gas flow rates in producing wells using thru-tubing wireline inflatable and retrievable packers or plugs to systematically isolate producing zones within a wellbore. Surface flow rates are measured before and after zonal isolation, with the zonal production rate determined by the measured difference in flow rate before and after isolation. Surface measurement of individual production zones allows greater accuracy in measuring multiphase flows, while at the same time allowing evaluation of reservoir properties of the lower, isolated zones.

Abstract: A method of, and apparatus for, measuring flow rates of highly viscous source fluids, having a flow rate wherein a secondary fluid of the same viscosity is injected at a predetermined measurable rate of flow into the stream of source fluid, where the source and secondary fluids are intermixed. The flow rate of the combined fluids is then measured, and the fluid rate of flow of the injected fluid is subtracted from the total flow rate measured, to determine the rate of flow of the source fluid.

Abstract: A fluid metering system includes a metering unit having a main flow channel and a bypass channel through which a portion of the total fluid flow through the unit is diverted, the bypass channel includes a fluid meter having means for monitoring a flow of fluid through the unit. The metering unit is optionally of modular construction including a number of components including a fluid meter.

Abstract: An apparatus for use in measuring fluid flow across a boundary is disclosed including a conduit, supply means for control fluid and two fluid flow sensors. The conduit is positioned to extend across the boundary so that its open ends are located on opposite sides of the boundary. The supply means introduces control fluid at an intermediate point so that control fluid flows through the conduit in opposite directions and discharges through both open ends. The fluid flow sensors are mounted so that each may sense variations in control fluid flow exiting at the ends of the conduit. These sensors generate output signals responsive to fluid flow across the boundary.

Abstract: A fast response control circuit for providing an output signal in miminum time after receiving an enabling input signal. The control circuit includes an amplifier which provides an output signal having a magnitude determined by a variable input signal when the enabling input signal indicates that an output signal is desired. A feedback network and the amplifier together define a control loop which has a characteristic response time. When the enable signal is absent, a bias control biases a reactive component in the control loop so as to minimize this response time. The circuit is adapted for use in a fluid mass flow controller to provide rapid response to an enabling input signal, particularly when a very low fluid flow rate is desired.

Abstract: In the context of a fan assembly for an air system comprising a bulkhead (20) and at least one fan (2) which extends through the bulkhead (20) and whose intake on the aspiration side and whose outlet on the pressure side are located in chambers (21 and 22) separated from each other by the said bulkhead (20), it is possible to obtain reproducible conditions for determining the volumetric performance if adjacent to the two sides of the bulkhead (20) there is in each case at least one pressure sensor (24 and 25) provided with a pressure gage connection (26 and 27).

Abstract: An apparatus for measuring an amount of ultrafiltrate produced in a hemodialyzer and a concentration of a receiving solvent employed in the hemodialyzer by means of an ultrasonic wave, comprises: an ultrasonic vibrator; each of an inlet and an outlet flow-rate measuring parts provided with an input flow channel and an output flow channel; and a reflector interposed between the inlet and the outlet flow-rate measuring parts to permit only the ultrasonic wave to pass therethrough, the reflector reflecting the ultrasonic wave so that the ultrasonic wave issued from one of the inlet and the outlet flow-rate measuring parts is directed to the other.

Abstract: The differential mass flowmeter comprises two U-shaped tubes, arranged side by side, mutually rigidly coupled, and having their ends inserted into a support. The tubes are adapted for conveying fluid in countercurrent and are provided with an electromagnet adapted for producing oscillation of the tubes about an axis passing through the portions inserted into the support, and with at least two coils, each facing a permanent magnet for generating a signal proportional to the angle of inclination of the portion of the small tubes which is opposite to the support, to thus permit continuous measurement of mass flow rate differences between two sections of a tube.

Abstract: An assembling method of a fuel injection valve for fuel injection into an internal combustion engine, the fuel injection valve including a cylindrical valve body having a fuel passage therein and a through-hole made in a direction of the axis thereof and a cylindrical nozzle coupled to the valve body and having a plurality of injection holes for dividing the fuel exited from the through-hole into a plurality of parts and for injecting the divided fuel parts into the engine. The assembling method comprises the steps of coupling the nozzle to the valve body, rotating the valve body relative to the nozzle, and stopping the rotation of the valve body when the through-hole takes a desirable position relative to the injection holes and fixedly securing the nozzle to the valve body.

Abstract: A method and apparatus for determining the gas flow rate in a high pressure critical flow nozzle is disclosed. A high pressure gas flows through a first critical flow nozzle. Upstream of the first critical flow nozzle a small slip-stream of gas is removed and flows through a smaller second critical flow nozzle. The small second critical flow nozzle drops the pressure of the gas to a low level. This flow rate of this low pressure gas stream is measured in a highly accurate low pressure gas flow rate measuring device. Since the flow rate in this device must be the same as that of the second critical flow nozzle, a correction factor can be calculated for the second critical flow nozzle. This flow rate correction factor will be the same for the first critical flow nozzle.

Abstract: An active attenuation system is provided for attenuating the pressure pulses in a liquid flowing in a pipe. The system includes an actuator for introducing nulling pressure pulses into the pipeline having the same frequency, but phase reversed to provide opposite amplitude of the pressure pulses to be attenuated. A plurality of pressure sensors are disposed in the pipe to sense the pressure pulses to be attenuated and these sensors are connected to a pressure transducer amplifier system which, in turn, is electrically connected to a control monitor which adaptively models the responses and continuously adjusts its output to a power amplifier which, in turn, signals the actuator to produce nulling pulses at the desired frequency and amplitude to attenuate the pressure pulses at a desired location, i.e. headbox or pipeline termination, in the liquid flowing through the pipe.

Abstract: A method and apparatus for determining the gas flow rate in a high pressure critical flow nozzle is disclosed. A high pressure gas flows through a first critical flow nozzle. Upstream of the first critical flow nozzle a small slip-stream of gas is removed and flows through a smaller second critical flow nozzle. The small second critical flow nozzle drops the pressure of the gas to a low level. This flow rate of this low pressure gas stream is measured in a highly accurate low pressure gas flow rate measuring device. Since the flow rate in this device must be the same as that of the second critical flow nozzle, a correction factor can be calculated for the second critical flow nozzle. This flow rate correction factor will be the same for the first critical flow nozzle.

Abstract: A sewer flow measurement method and system for determining flow conditions of a sewer line system wherein separately located monitors make and record precisely synchronized and time identifiable pressure measurements, utilizing pressure-to-signal transducers positioned on the bottom of pipes where they exit into manholes. A cassette recorder records the different pressure related signals from the monitors together with a discrete identification signal from each monitor. The outputs of the recorder are then fed to a pressure-to-flow computer which provides location identified, time synchronized, flow data for the system.

Abstract: A mixture of two materials flows through a first measuring station which includes a Venturi meter for obtaining and measuring a pressure difference .DELTA.p that is representative of mass flow rate of the mixture and velocity. The mixture then flows through a second measuring station which includes a temperature differential flowmeter in which a predetermined amount of heat is supplied to heat the flowing mixture and raise its temperature to obtain and measure a corresponding change in temperature that is related to the mean density of the mixture and also the square of the mass flow rate. These values .DELTA.p and .DELTA.t are inputs to computer means which functions to solve a third order polynominal or cubic equation and express that solution in terms of the mixture ratio and flow rates of the individual components and the flow rate of the mixture itself.

Abstract: IA purge block is disclosed in which inlet, process, purge and vent ports are series connected in a ring or bridge. The channel or passageway connecting the inlet and purge ports comprises a flow sensor. The impedance to gas flow of each channel is different from the others. The impedances are chosen such that improper operating conditions cause an imbalance in the flow which is detected by the flow sensor. During normal operation of the system in which the purge block is used, the flow sensor acts as an excess flow detector by comparing the flow through itself with the flow through a parallel, but more restrictive, path within the purge block.

Abstract: In a ventilating hood of the type incorporating a supply chamber, an exhaust outlet, one or both of which incorporate air blower or moving means, such as fans, pressure taps are incorporated at strategic locations about the supply and exhaust chambers, generally at the location of their separating partitions, as where the air is diffused as passing through the hood, so that pressure drops can be readily determined, and airflows at these locations may be properly set as determined from previously prepared graphs.

Abstract: A method for determining the amount of dissolved oxygen in the aqueous medium from a steam generator system that results from air leakage into the system above the water level in a condensor hotwell and that which results from air leakage below the water level in the condensor. Intentional injection of air above water level and intentional injection of air below water level are effected and resultant dissolved oxygen contents measured. The air leakage rate and dissolved oxygen contents at steady state operation are also measured. From these measurements, the amount of dissolved oxygen resulting from above and below water level are determined mathematically or graphically.

Abstract: An apparatus for measuring the relative flow of pulverized coal in a plurality of pipes connected between a common pulverizer and respective burners comprises a plurality of electric charge sensors each disposed in a similar position on the plurality of pipes. The electric sensors sense an induced signal produced by charged pulverized coal particles. For unbiased flow, the induced signal is proportional to the amount of flow in each pipe as the charge properties of the particles from the pulverizer are the same for all the pipes. A circuit is connected to the sensors for obtaining a root means square value of the induced signal which in turn is compared to each induced signal respectively to obtain a measurement of the relative flow in each pipe. The induced signal can be integrated twice to improve the correlation between flow and charge amount since the integrated value is independent of radial position for the charges in the pipes.

Abstract: To measure a wide range of flow rates, and particularly such low flow rates as 0.5 liters per hour, while being able to accurately also measure rates of about 100 liters per hour, fluid is introduced axially into a rotor (14, 36, 40) which has outlet openings (24, 36, 45) positioned at their circumference, the rotor being rotated by reaction on the rotor upon fluid flow from the outlet openings. The rotor operates within a fluid flow chamber (15) from which is conducted outwardly through a duct positioned thereabove. Inflow of fluid may be guided for linear flow by guide ribs (13). The rotor may be a hollow disk-like structure (FIGS. 1-3) with spiral guide vanes therebetween, or a T-shaped tubular structure (FIGS. 4-6).

Abstract: A device for measuring a differential flow rate between a foward flow to a user station and a return flow from the user station, particularly well-suited for measuring fuel consumption in motor vehicles with a fuel return line extending between the carburetor or the injection pump and the fuel tank, includes a flow measuring chamber having an ultrasonic measuring arrangement. The flow measuring chamber is comprised of a forward flow tube portion and a return flow tube portion interconnected with one another along an ultrasonic wave path. Within the ultrasonic wave path, there is contained a partitioned wall means, permeable to ultrasonics, which serves to prevent flow communication between the two tube portions. First and second ultrasonic transducers are positioned at opposed ends of the ultrasonic wave path, the first transducer being formed on the forward tube portion and the second transducer being formed on the return tube portion.

Abstract: A sewer flow measurement method and system for determining flow conditions of a sewer line system wherein separately located monitors make and record precisely synchronized and time identifiable pressure measurements, utilizing pressure-to-signal transducers positioned on the bottom of pipes where they exit into manholes. A cassette recorder records the different pressure related signals from the monitors together with a discrete identification signal from each monitor. The outputs of the recorder are then fed to a pressure-to-flow computer which provides location identified, time-synchronized, flow data for the system.

Abstract: A temperature sensor uses a thin film structure having an RF sputtered layer of a temperature sensitive material forming a thermistor element deposited on an electrically insulating and thermally insulating substrate. The sensor may include a plurality of deposited thermistor layers arranged on both sides of the substrate and having electrical connection means attached thereto. The sensor is arranged on a substrate suitable for inclusion in a detector cell forming a chamber arranged to be connected to a source of fluid flow.

Abstract: A flowmeter head is in the form of side-by-side channels of non-magnetic, electrically insulating material with the channels of very similar size. Sufficient precision of channel size is attained by boring the channels or by using drawn tube of closely controlled size. A radial electrode is provided in each channel, e.g. by drilling a fine hole in the channel wall and sealing a wire in. The electrode arrangement permits an applied magnetic flux to pass through first one channel, then the other. Earth electrodes are provided at the ends of each channel. An earth-loop free connection to a differential amplifier of a flowmeter apparatus is possible with the electrode configuration. The precision of the channel size improves common-mode accuracy and the earth-loop free connection reduces drift and noise.

Abstract: A gas comparison probe contains first and second sensor elements isolated om each other. Air is drawn across a surface to be monitored and directed onto the first sensor element. Air is drawn from a location spaced away from the surface to be monitored and directed onto the second sensor element. A flow constrictor in the air flow path to one of the sensor elements is used to calibrate the outputs of the two sensor elements under known conditions before attempting to monitor air flow which may contain a gas to be detected.

Abstract: In a fluidized bed reactor having a reactor vessel, two detector vessels are mounted in the reactor vessel near the inside surface of the reactor vessel in the fluidized bed and in the gas outlet region. Each detector vessel contains larger detecting particles and passes the gas in the reactor vessel. Pressure drop across the detecting particles is measured. The ratio of the two pressure drops represents the ratio of the fluid velocity and minimum fluidizing velocity under the operating conditions and can be used as control factor.

Abstract: Apparatus for measuring fluid pressure and velocity, and in particular for maintaining an aspirator air velocity constant under varying atmospheric conditions. A precisely controlled air velocity is provided by a reference air source whose frequency is derived from a crystal oscillator. The total air pressure from the aspirator wind tunnel is compared with the total air pressure from the reference air source using a matched thermistor pair technique to convert the pressure difference into an electrical error signal which is used to control the main air source for the aspirator wind tunnel such that the error signal is maintained at zero, thereby maintaining the air velocity in the aspirator constant.

Abstract: The present invention relates to a process and apparatus for preparing flowable reaction mixtures.

Abstract: A method and apparatus to monitor a compressible gas volume of one or more hydropneumatic storage tanks of an energy-storing system includes at least one pump to fill the individual storage tanks with hydraulic fluid. The fluid is isolated from the gas volume in each storage tank or unit by a movable partition. The gas volumes of the storage tanks are monitored continuously and free of error for the early detection and signaling of gas volume losses by the use of a minimum of maintenance-free devices. The monitoring is accomplished by determining the state of flow of the hydraulic fluid entering the several hydropneumatic storage tanks while the pump is running. In the event of a coincidence of a running pump and an interruption of the flow to a tank, a loss of gas volume is indicated. A flow monitor having a control contact within each pipeline supplying the hydraulic fluid as well as a signal device for indicating the pump operation is provided.

Abstract: A current/flow comparator for generating an alarm signal whenever the instantaneous flow rate of a coolant fluid cooling the armature of a dynamoelectric machine falls below a predetermined percentage of a desired instantaneous flow rate, which desired flow rate varies as a function of the square of the instantaneous current flowing through the armature, is disclosed.

Abstract: Two pressure-receiving members are provided within a proportional valve interconnecting a main pipe and a bypass line.The ratio of the rate of fluid flow in the main pipe to the rate of fluid flow in the bypass is held constant by moving vertically a valve plug within the proportional valve by the forces developed by the differential pressure placed across each of these two pressure-receiving members and by adjusting the rate of fluid flow in the bypass so as to keep a constant ratio of the pressure differential created across a restriction in the main pipe to the pressure differential created across a restriction in the bypass. Therefore the rate of fluid flow in the main pipe can be determined from a measurement of the rate of fluid flow in the bypass.

Abstract: A hydraulic system is supervised in order to detect leakage by comparing the flows in two conduits of a hydraulic power consumer. Rotatable flow sensitive means are mounted in each of the conduits. Means are provided to indicate the change of the rotational speed of at least one of the flow sensitive means caused by leakage in the hydraulic system.

Abstract: A technique for monitoring the frequency difference between pulse output signals derived from a pair of flowmeters interposed respectively in the inlet and outlet lines of a flow conduit supplying cooling water to the tuyere of a blast furnace, the frequency difference being indicative of water leakage. The furnace has a plurality of such tuyeres, each conduit of which is monitored. The pulse output signals from the flowmeters at each monitoring point are fed to a common processing unit in which there are stored the constants representing the instrumental error between each pair of flowmeters as well as their mean conversion constants. In the processing unit, computations are carried out on the basis of the pulse output signals derived from each pair of flowmeters, the instrument error constant thereof and their mean conversion constants, in order accurately to determine the flow rate difference therebetween at each monitoring point independently of the instrumental error.

Abstract: A system for monitoring the frequency difference between pulse output signals derived from a pair of flowmeters interposed, respectively, in the inlet and outlet lines of a flow conduit supplying cooling water to the tuyere of a blast furnace, the frequency difference being indicative of water leakage. The pulse output signals produced by the respective flowmeters during each predetermined measuring period are integrated. The integrated values are compared with each other, the difference therebetween being monitored whereby when the difference exceeds a predetermined set value, an alarm is generated.

Abstract: This invention relates to an improved method of monitoring the mass flow rate of a substance entering a cocurrent fluid stream. The method very basically consists of heating equal sections of the fluid stream above and below the point of entry of the substance to be monitored, and measuring and comparing the resulting change in temperature of the sections. Advantage is taken of the difference in thermal characteristics of the fluid and the substance to be measured to correlate temperature differences in the sections above and below the substance feed point for providing an indication of the mass flow rate of the substance.

Abstract: The present invention is a method and apparatus for monitoring in real time the mass and energy flow rate of a gas through a pipeline. The invention determines the mass flow ratio of a pipeline gas flowing through a pipeline compared to sample gas tapped from the pipeline line when the volumetric flow of pipeline gas through the pipeline is measured by a linear flow meter. Sample gas tapped from the pipeline is flowed to a chamber having a section with a fixed volume until the pressure in the chamber section is substantially equal to the pipeline gas pressure. The sample gas is maintained at substantially the same temperature as the gas in the pipeline while the sample gas is in the chamber section. A timer measures the time interval for the sample gas to flow from the chamber section at a selected rate for a calculated pressure drop the selected rate being controlled by a flow controller. The mass flow ratio is computed using the measured time interval and a signal from the linear flow meter.

Abstract: Methods and an apparatus for measuring gas flow with greater reliability than earlier single-rotor and double-rotor turbine meters and dual turbine meter systems are disclosed. The apparatus comprises two independent rotors, in close proximity of each other, housed in the same meter body, but isolated from the effects of each other. No pressure and temperature correction are needed for accuracy performance comparison between the two rotors. Because of the two rotor averaging technique, the reliability of the volume totalization is greatly improved over earlier double-rotor and single-rotor designs.