Abstract: The present disclosure relates to a fluid level sensing system for sensing a fluid level in a well. The system has an upper housing in communication with a lower housing, with the lower housing having a first bore in communication with a fluid in the well, and a second bore isolated from the first bore and in communication with at least one of a vacuum gauge or an external vacuum source. The upper and lower housings house a first flexible bag and a second flexible bag, with the first bag housed within the second bag. A portion of the first bag communicates with the first bore and is responsive to a change in pressure within the first bore caused by a changing fluid level in the well. A portion of the second bag communicates with the second bore and exerts a reference pressure on the first bag. A sensing subsystem senses expanding and contracting movement of the bags and generates a signal indicative of a change in a level of the fluid in the well.

Abstract: To measure above-saturation water content of hydrocarbons, a liquid hydrocarbon sample is received from a flowline carrying the liquid hydrocarbon. The liquid hydrocarbon sample includes liquid hydrocarbon and liquid water at a concentration greater than a water saturation level. The liquid hydrocarbon sample is mixed with a solvent. The concentration of liquid water in a mixture of the solvent and the liquid hydrocarbon sample is below the water saturation level. After mixing the liquid hydrocarbon sample with the solvent, a water content in the liquid hydrocarbon sample is determined.

Abstract: Disclosed are methods in which measurements are obtained from a plurality of sensors secured in spaced relation to one another across at least a portion of the depth of reservoir of some form in order to identify one or more characteristics of the fluids within the reservoir. The sensors are used to monitor ambient forces exerted by fluids within the tank proximate each sensor. An example mechanism for obtaining the measurements includes a plurality of sensors, such as strain gauges, supported on a structure that supports the sensors in fixed relation to one another, and can, in some examples, support the sensors in a known relation relative to boundaries of the reservoir.

Abstract: A system for performing inline measurements of flow rate, density, and rheology of a flowing fluid is disclosed, comprising: (a) a rheology measurement subsystem comprising: a horizontal tube of internal radius rH; means for measuring a velocity profile of a test fluid flowing through said horizontal tube at a distance x0 from its upstream end; and means for determining wall shear stress at a boundary between said flowing fluid and an inner surface of said horizontal tube; (b) a density measurement subsystem comprising: a vertical tube of internal radius rV in fluid connection with said horizontal tube; a pressure sensor for measuring the pressure of said test fluid within said vertical tube at a location y1; and, (c) a pressure sensor for measuring the pressure of said test fluid within said vertical tube at a location y2 downstream from y1 and displaced vertically from y1 by a distance ?h.

Abstract: According to one aspect, a lubricant level sensing system for an actuator is provided. The lubricant level sensing system includes a pressure port in an outer housing of the actuator, a pressure sensor, and a pathway from the pressure port to the pressure sensor. The pathway establishes fluid communication between the pressure sensor and a free volume of an internal cavity of the outer housing relative to a lubricant level in the internal cavity such that the pressure sensor detects a pressure of the free volume used to derive the lubricant level.

Abstract: A measurement device for performing measurements on a mixture of water and collected material includes a pipe section through which the mixture can be guided. The pipe section includes a window. The measurement device further includes an image capturing device arranged to capture an image of the collected material through the window. The image can be used to determine a grain size distribution of the collected material, which can be used to optimize the collecting process.

Abstract: A system of performing inline measurements of flow rate, density, and rheology of a flowing fluid. The system includes a rheology measurement subsystem, a density measurement subsystem, and a pressure sensor for measuring the pressure of the test fluid within the vertical tube at a location y2 downstream from y1 and displaced vertically from y1 by a distance ?h.

Abstract: A method for estimating equivalent top of fluid level or a theoretical surface annular back pressure in a subterranean wellbore includes acquiring first and second axially spaced pressure measurements in the wellbore. The pressure measurements may then be processed to compute the equivalent top of fluid level and/or theoretical surface annular back pressure of drilling fluid between the measurement locations. A tool string including a large number of axially spaced pressure sensors (e.g., four or more or even six or more) electronically coupled with a surface processor via wired drill pipe may be used to obtain a plurality of values corresponding to various wellbore intervals. The equivalent top of fluid level and/or theoretical surface annular back pressures may be used in automated managed pressure drilling operations.

Abstract: An apparatus and method used to determine the density and other properties of a corrosive liquid, such as drilling mud. The apparatus uses at least two sensor elements with ceramic facings spaced a known vertical distance apart and inserted into the fluid. The differential pressure measurement provided by these sensors is used to calculate the density of the liquid. This density measurement is then reported in real-time to an operator.

Abstract: A hydrostatic tester is provided with an elevated test surface allowing tests to be made inside sleeves, pants legs or other hard to reach locations of completed garments. A constant force spring is engaged by way of a straight line clamp to apply pressure and maintain a consistent and constant force on a sandwich seal. A clamping mechanism can be moved to the left or right of test area to provide a clear unobstructed access to position test item. A raised gasket on the test surface prevents hard contact between test surface and seal ring avoiding damage to test items. A blood pressure bulb is used as a pressure source to force water from a reservoir to the test area. A low pressure gauge is positioned for easy viewing to monitor test pressure.

Abstract: A hydrostatic sensor device and method is provided for detecting changes in elevation in pipes, boreholes, and tunnels below ground. A pressure transducer for sensing differential changes in fluid pressure is provided at one end of an extensible hose or other flexible conduit, while the other end is maintained in an equalizer tank at a reference atmospheric pressure at a given elevation. As one end of the system is moved along a grade, pressure changes at the transducer end relative to the reference pressure at the equalizer end are measured corresponding to elevation changes and are recorded against a distance scale, thus providing an accurate profile of the line surveyed.

Abstract: A hydrostatic testing tool for testing containers, hoses or the like under high pressures. The testing tool having a coupling that threadably engages a threaded aperture of a test container without having to be rotated into the threaded aperture. The hydrostatic testing tool may be hooked up to a source of pressurized medium and the tool includes a container-engaging head having a plurality of collet segments that each have a threaded surface that can expand radially outward, partially due to the force of the pressurized medium, to engage a threaded aperture of the test container, allowing for the formation of a liquid and/or gas tight seal under high pressures. The testing tool further includes an actuating unit connected to the head that controls the movement of the collet segments with a piston or the like.

Abstract: An apparatus for determining the density of insulation in a cavity of a structure that senses a force of the insulation against the sensor. The force is used to determine the density of the insulation, which, in turn, is used to determine the thermal resistance or R-value of the insulation. The apparatus may include a fixture for supporting the sensor and holding the sensor in the substantially fixed position. A method for determining the density of loose-fill, blown-in-place insulation in a wall cavity by the use of a sensor is that measures a force exerted on the sensor by the insulation. The measured force is used to determine the density of the insulation. The thermal resistance of the insulation is determined from the known cavity depth and insulation density.

Abstract: A hydrostatic testing toll for testing containers, hoses or the like under high pressure. The testing tool having a coupling that threadably engages a threaded aperture of a test container without having to be rotated into the threaded aperture. The hydrostatic testing tool may be hooked up to a source of pressurized medium and the tool includes a container-engaging head having a plurality of collet segments that each have a threaded surface can expand radially outward, partially due to the force of the pressurized medium, to engage a threaded aperture of the test container, allowing for the formation of a liquid and/or gas tight seal under high pressures. The testing tool further includes an actuating unit connected to the head that controls the movement of the collect segments with a piston or the like.

Abstract: A sensor for measuring properties of a fluid in a vessel, includes a sensor mount adapted to mount within a wall of a vessel; a sensor body extending substantially vertically from the sensor mount; and a plurality of sensors spaced vertically along the sensor body, whereby at least one of level, density, temperature and pressure of fluid in the vessel can be measured.

Abstract: It is an object of the present invention to provide a touch mode capacitive pressure sensor having higher pressure durability than conventional sensors. In this invention, a touch mode capacitive pressure sensor has a diaphragm made from boron-doped silicon, and the boron concentration at the top face of the diaphragm is equal to or greater than 1×1019 cm?3 and less than 9×1019 cm?3. Further, in this invention, a touch mode capacitive pressure sensor has a conductive diaphragm made by doping of an impurity and anisotropic etching, and the etch pit density on the top face of the diaphragm is equal to or less than five per ?m2, and preferably equal to or less than one per ?m2. As a result, the pressure durability of the diaphragm is greatly improved.

Abstract: The invention relates to a device (2) for determining the density of an electrolyte (4). Said device (2) comprises at least two immersion tubes (9, 10) provided with an open orifice (52) and immerging at different depths in the electrolyte (4), whereby said immersion tubes can be respectively filled with gas to a depth (21, 22) which is allocated thereto and each tube has a different gas depth (d) with respect to the other. A least one differential pressure sensor (16) is used to define the difference in pressure inside the immersion tubes (9, 10). An electrode (11, 19) is respectively provided inside the immersion tubes (9, 10), whereby said electrode is connected to a voltage source (5, 35) in order to produce the required depth (21, 22) of gas so that said immersion tubes (9, 10) can be filled therewith upon contact with the electrolyte(4).

Abstract: The current invention provides a process and apparatus for determining the density of a flowing fluid without requiring knowledge of the fluid's Theological properties. The process of the current invention is capable of providing continuous “real time” analysis of fluid density. The apparatus of the current invention comprises at least two pressure assessment zones fitted with fluid pressure sensing points. Pressure sensing devices connected to the pressure sensing points provide the data necessary to enable the calculation of fluid density.

Abstract: An assembly adapted to be affixed to a container which contains a sample fluid, and a method of affixing the assembly to the container, are provided. In particular, a contact pressure can be applied to a surface of the container, such that a particular arrangement, which has a portion situated within an opening of the container, is affixed to the container without piercing the surface of the container. For example, the container can be a tank, the particular arrangement can be a sensor arrangement, and a further arrangement can be used to affix the particular arrangement to the container. Moreover, the contact pressure preferably can be applied to an exterior surface of the container so that the further arrangement may be more accessible to a user of the assembly.

Abstract: An in-situ sensor system and method which measures the density of a liquid accurately with pressure sensors by measuring pressure in the liquid at two separate positions defined by a fixed distance. The fixed distance is known accurately to at least the nearest 0.0001 inch by measuring temperature simultaneously with pressure measurements. The temperature is used to correct for temperature-related changes in length of the material to which the pressure sensors are fixed. Because pressure sensors and temperature sensors can be relatively small, the sensor system is small, portable, and can be easily and safely inserted into or removed from tanks through a small opening. A data acquisition system acquires data with a remote telemetry system, provides the data to users through a communications network, and provides density, height, volume, and leak rate of the liquids using one or more data management systems.

Abstract: The current invention provides a process and apparatus for determining the density of a flowing fluid without requiring knowledge of the fluid's Theological properties. The process of the current invention is capable of providing continuous “real time” analysis of fluid density. The apparatus of the current invention comprises at least two pressure assessment zones fitted with fluid pressure sensing points. Pressure sensing devices connected to the pressure sensing points provide the data necessary to enable the calculation of fluid density.

Abstract: The device includes a pipe section in loop form having two arms which make an angle with the horizontal, which arms each contain two pressure sensors which are located some distance apart in the direction of flow, as well as a processing unit, connected to the pressure sensors, for determining the density of the medium on the basis of the pressures or an associated parameter measured by the sensors. The pipe section in loop form is connected in parallel to the pipeline.

Abstract: A pair of solid state pressure sensors are disposed near the bottom of a fuel tank vertically spaced with one a unit distance above the other. A third solid state sensor is disposed in the tank at the highest point under the upper wall. The apparent hydrostatic pressure is computed from the difference in pressure sensed by the highest and lowest sensors. The density is computed from the difference in pressure sensed by the pair of sensors near the tank bottom; and, the difference normalized for the vertical distance therebetween. The liquid level height is then computed from computed density and apparent pressure. The reserve volume of liquid fuel is then found for the computed height from a lookup table of values of liquid height and corresponding liquid volume.

Abstract: A density monitoring assembly for use in monitoring the gas density within a high voltage circuit breaker tank is disclosed. The density monitoring assembly is coupled directly to an exterior surface of said tank and provides electrical signals indicative of the density of gas within the tank. The assembly comprises a cover that encloses the density monitoring device. The device itself is used to retain the cover. A ball valve and a shraeder type valve are provided to allow testing of the device.

Abstract: A system and method for obtaining a fluid density of a fluid in a tank includes, for example, a first sensor coupled to a second sensor through an extension. The two sensors are coupled to a transmitter. The sensors are lowered into the fluid of the tank such that the first sensor is positioned at a first fluid level and the second sensor is positioned at a second fluid level. Fluid pressure at the two levels is sensed by the two sensors which affects the fluid pressure of a fill fluid inside the housing of the system. The effect on the fluid pressure of the fill fluid is sensed by the transmitter which creates an electrical signal relating to the fluid pressures sensed by the two sensors. A calculating device may determine the fluid density of the fluid in the tank from the signal received from the transmitter.

Abstract: A pressure data validation method which measures differential pressure along with measuring the absolute pressure while testing a well. The method uses a differential pressure gauge having a known distance between the two differential pressure measuring gauges, wherein the pressure differential indicates fluid density. During the test, as each absolute pressure reading is taken, a differential pressure reading is also taken and this reading is used to determine the density of the fluid surrounding the gauge at the time of the measurement. Each measurement is compared to previous measurements, and a change in fluid density, and thus a change in the type of fluid, is displayed to indicate that any discontinuity in the pressure display is due to a fluid boundary.

Abstract: A system and method for obtaining a fluid density of a fluid in a tank includes at least two sensor/transmitter assemblies to obtain fluid pressure measurements at different fluid levels in the tank. After the respective fluid pressures are obtained, the fluid density is calculated as a function of the respective fluid pressure measurements. The sensor/transmitter assemblies have substantially similar variation characteristics so that possible measurement variations are eliminated during fluid density calculations.

Abstract: An apparatus for applying solder enhancing liquid flux to objects for soldering including a fluxer wherein the density of the liquid flux supplied to the fluxer is controlled by a device for determining the density intermediately a flux storage container, and the fluxer; the density determining device producing an output signal whereby the quantity of diluent supplied to a liquid flux storage container is controlled. The density determining device includes a liquid flux pressure measurer with a vessel extending thereabove which includes an overflow to maintain constant flux liquid level therein.

Abstract: An apparatus and method for maintaining continuous flow in a closed loop test system, of a multiphase composition such as that utilized and obtained from oil and gas wells and the like. The method and system provide a test structure whereby a study of the changes in a multiphase composition (gas/liquid/solid) flow can be studied. Specifically, the method and apparatus provide for pressure boosting the gaseous components of the multiphase composition after separation from the liquid and solid components of the system. A hydrostatic head through which the liquid and solid components flow provides the necessary potential energy-kinetic energy exchange such that when the pressure boosted gas is recombined with the downcomer liquid/solid components, continuous flow of the multiphase composition is maintained. Pressure and temperature controls permit the accurate maintenance of pressure, temperature and flow conditions so as to imitate a real-world environment for multiphase composition flow.

Abstract: The present invention is a differential pressure fluid density instrument comprising a housing having a plurality of ports positioned at spaced-apart locations along the housing, a differential pressure transducer, and a valve adapted to selectively connect the transducer across two predetermined one of the plurality of ports. The valve may comprise a three-way solenoid actuated valve. Fluid expansion wells are each connected at one end to a port and prevent wellbore fluids from reaching the differential pressure transducer. The housing includes an inner chamber filled with liquid which may be silicon oil. The chamber includes a standpipe which extends from near the bottom of the chamber, where it is in communication with a lower port, to the top of the chamber. Communication between the chamber and wellbore through the standpipe enables the housing and components disposed within the chamber to be constructed without the need to withstand high differential pressures.

Abstract: A method and system are provided for monitoring the pressure of gas in a gas filled circuit breaker container based on a temperature compensated gas pressure signal which is compared with a signal representing a desired gas pressure in the container to provide a signal indicating a gas leak when the actual pressure is less than the desired pressure. In addition to identifying a gas leak, the method and system is operable to deactivate the circuit breaker when the actual pressure decreases below a predetermined low pressure, to determine the gas leak rate and to deactivate the circuit breaker if the leak rate is greater than a predetermined acceptable rate and, otherwise, to determine the time required for the pressure to decrease to the unacceptable low pressure, and to activate an alarm, visual display and/or recording of information in response to certain detected conditions with respect to the gas pressure.

Abstract: A high voltage switching apparatus 10 is described containing an arc-quenching gas containing sulphurhexafluoride in a vessel 12 that is monitored by a gas monitoring device 20. A temperature transducer 34 is attached to the exterior of the vessel 12 to sense the temperature of the gas. A gas line 24 leads from a control panel 18 to an enclosure 22 of the device 20. The device 20 has a front display panel with a digital communication terminal 42 for connecting to a computer to load and download data to and from the device 20 relating to the density of the gas within the vessel 12. The device 20 includes a data input module 44, a control module 46, a relay module 48, a display module 50 and a DC power supply module 52 mounted in an enclosure 22. The enclosure 22 has an internal heater 56 for maintaining the temperature within the enclosure above 20.degree. C.

Abstract: Fluid level in a container is determined using a single pressure transducer connected to a portable body. The body contains a computer having a memory in which fluid level-to-fluid volume conversion data are stored for different shapes of containers so that fluid volume can be readily obtained for the shape of the respective container once fluid level is determined. These features allow a single monitoring apparatus to be used for monitoring different types of containers. The apparatus preferably includes a radio so that multiple apparatus can communicate in a system with a central remote operator interface device. Fluid level is determined by dividing a pressure reading from the bottom of the fluid by a fluid density determined from two prior pressure reading taken across a known distance (density equals the difference between the two readings divided by the distance).

Abstract: Fluid level in a container is determined using a single pressure transducer connected to a portable body. The body contains a computer having a memory in which fluid level-to-fluid volume conversion data are stored for different shapes of containers so that fluid volume can be readily obtained for the shape of the respective container once fluid level is determined. These features allow a single monitoring apparatus to be used for monitoring different types of containers. The apparatus preferably includes a radio so that multiple apparatus can communicate in a system with a central remote operator interface device. Fluid level is determined by dividing a pressure reading from the bottom of the fluid by a fluid density determined from two prior pressure reading taken across a known distance (density equals the difference between the two readings divided by the distance).

Abstract: Fluid level in a container is determined using a single pressure transducer connected to a portable body. The body contains a computer having a memory in which fluid level-to-fluid volume conversion data are stored for different shapes of containers so that fluid volume can be readily obtained for the shape of the respective container once fluid level is determined. These features allow a single monitoring apparatus to be used for monitoring different types of containers. The apparatus preferably includes a radio so that multiple apparatus can communicate in a system with a central remote operator interface device. Fluid level is determined by dividing a pressure reading from the bottom of the fluid by a fluid density determined from two prior pressure reading taken across a known distance (density equals the difference between the two readings divided by the distance).

Abstract: A specific gravity control apparatus 200 is disclosed which uses a plurality of electrodes 202, 204 and 206 to measure the height of a control liquid within a leg 8 to provide enhanced control of the specific gravity of the solution S. In a specific gravity control apparatus 250, a flexible diaphragm 254 isolates the solution from a control fluid. This permits a nonconductive solution to be maintained at a specific gravity by the apparatus using at least one electrode to measure the level of the control liquid which can be conductive.

Abstract: A level measuring system for measuring the level of a fluid in a tank employing tubes through which gas is passed extending to different levels in the fluid, whereby the level may be measured by comparing the differences in pressure necessary to release bubbles from the tubes. The ends of each of the tubes are bent at substantially a right angle, with the tips cut off at an angle so that the gas/liquid interface of the bubbles are at a more constant depth, and the bubbles are prevented from sagging.

Abstract: Method and system for measuring vertical density profile of fluid by pressurizing an array of pipes, determining level and pressure signals on each pipe and deriving profile therefrom.

Abstract: An instrument (10) particularly suited for use for purposes of measuring the presence of suspended solids in a slurry. The subject instrument (10) is comprised of a floating probe portion (12), a long tubular member (14) and an energy dissipating baffle (16). The tubular member (14) is suitably attached to the floating probe portion (12) by virtue of having one (18) of its ends affixed to the middle of the floating probe portion (12). The energy dissipating baffle (16) which is suitably mounted in supported relation to the other end (20) of the tubular member (14) preferably is in the form of a cylindrical member (24) that is divided internally into essentially three chambers (26,28,30) by means of two deflector plates (32,34). The two deflector plates (32,24) are each perforated (36) and are mounted within the interior of the cylindrical member (24) so as to be inclined relative to the longitudinal axis of the cylindrical member (24).

Abstract: A fuel energy analysis system is disclosed utilizing a first hydrostatic sensor, calibrated to specific fuel tank geometries, to monitor fuel quantity; and an additional hydrostatic sensor located at a different geometric height from said first sensor, allowing determination of specific gravity through hydrostatic pressure, and thereafter computation of energy content as a function of mass. This system is particularly suitable for harsh environments such as vehicular applications wherein the quality of fuel input to a tank may frequently vary, and is readily corrected for fluid motion in the tank, by the addition of additional sensors in conjunction with baffles.

Abstract: This invention relates to apparatus for determining the amount of liquid in a tank by measuring the pressure at the bottom and at a height above the bottom of the tank, and provides apparatus for compensating for apparent volume measurement variations caused by expansion and contraction of the tank and liquid with variation in temperature. A tube which expands in length at an exactly compensating rate varies the height of the second pressure sensor relative to the first. A further embodiment is a pneumatic system which avoids the necessity to immerse the pressure sensor, and utilizes an inexpensive single differential pressure transducer instead of two, and which cancels out the effect of any changes in zero setting of the transducer, changes in sensitivity of the transducer, or changes in atmospheric pressure.

Abstract: A system for measuring the density of a hydrostatic liquid in a container includes a pair of serially connected pressure sensors mounted in the liquid, a constant volume gas flow source connected to an inlet of one pressure sensor, a second pressure sensor connected to the outlet of the first pressure sensor, and a vent is connected between the second pressure sensor outlet and the atmosphere. A gauge or pressure transducer in the gas conduit from the source to the first pressure sensor provides pressure measurements that can be used to determine the level of liquid in the container and a differential pressure transducer across the first pressure sensor can be used to determine density of the liquid. Exhaust gas from the pressure sensors is passed to the atmosphere through a pressure buffering device in one construction of the system. The pressure sensors each have a rigid body with a generally circular resting surface over which a flexible diaphragm member is positioned.

Abstract: A hydraulic liquid pressure sensor for use in a gas operated pressure sensor system includes a sensor body with a generally circular membrane resting surface, an inlet connected to a peripheral portion of the surface and an outlet opening from a central location on the surface. A flexible membrane is positioned adjacent to the resting surface and in flush contact therewith when not in use. The flexible membrane is secured and sealed around the periphery of the circular membrane resting surface. The inlet includes an annular groove in the pressure sensor body and spaced around substantially outward of the outlet opening. The inlet also includes an additional groove in the sensor body opening to the resting surface, connected to the annular inlet groove and extending inwardly therefrom.

Abstract: A density meter includes a main body having a vertically elongated chamber to contain a test fluid. A passageway in the main body connects to the chamber near its bottom end. The passageway spans at least a bottom portion of the chamber and leads to the exterior of the main body. The chamber has in its lower end a liquid which is immiscible with and denser than the test fluid, the liquid also occupying at least part of the passageway. Access means are provided for admitting the test fluid to the chamber and evacuating it therefrom. Measuring means are provided for determining the location of the top surface of the liquid. The measuring means to determine the location of the liquid top is preferably ultrasonic.

Abstract: A method of and an apparatus for the measurement of the degree of gas charging of a liquid component of a foam synthetic resin such as a polyurethane. The gas-charged liquid component is introduced into a measuring vessel to a height controlled by an overflow so as to be fixed. The degree of charging is then determined from the measured hydrostatic pressure of each column.

Abstract: A method of and apparatus for the measurement of the degree of charging of a liquid synthetic resin component with a gas in which the flushing of the measuring column and the detection of the hydrostatic pressure are effected solely by control of the intake valve to the measuring chamber, a discharge valve at the bottom of an overflow chamber connected to the measuring chamber, and a three position valve connected to the top of the overflow chamber. In one position of this latter valve, a pressurized gas is applied to the overflow chamber to drive overflow liquid component back to the tank: in another position of this valve the column can be equilibrated with atmospheric pressure: in a third position this valve is closed.

Abstract: Liquid differential pressure measurement apparatus using at each of two separate vertical locations a manifold with a pair of voids, each pair being covered with a thin, non-elastomer membrane pressing tightly against a horizontal fence line therebetween. A first void of each pair is gas pressurized from the external side of the manifold to move the membrane on the internal side of the manifold outwardly against the pressure head of liquid on the membrane at the location of the fence line, the gas escaping via the second void, which is vented. A meter connection to the first void of each pair is supplied to a differential pressure meter and/or a device that converts a differential pressure to an electrical signal for remote readout or the like.

Abstract: Apparatus for measuring the total mass of the fluid in a container, having pressure responsive, density determination means adapted to determine the localized density of the fluid as a function of pressure differential between two closely spaced, vertically separated measuring points in the fluid, means enabling the density determination means to determine the localized density values throughout the depth of the fluid, storage means for storing predetermined horizontal cross-sectional area values of the container as a function of depth, and computational circuitry responsive to the density determination means and the storage means for providing a total mass signal corresponding to the integral, over the depth of the fluid, of the product of localized density values times the corresponding area values.

Abstract: Apparatus is provided for measuring the concentration of particulate or fibrous material in a fluid flow in part of a flow line. The concentration is measured by detecting the recovery pressure downstream of a pressure reducing unit.

Abstract: A liquid sensing and gauging method and apparatus employing a differential pressure sensing device located near the bottom of the tank and an absolute pressure sensing device located at the same level as one of the differential pressure sensing device elements. The differential sensing device is connected for driving the arm of a potentiometer included in an electronic circuit to develop an intermediate voltage exponentially proportional to the reciprocal of the specific gravity of the tank liquid. Similarly, the absolute pressure sensing device is connected for driving the arm of a potentiometer which is biased by the intermediate voltage. The output on this arm is then indicative of the height of the tank liquid only, regardless of the specific gravity of the liquid. The height level output can be multiplied by an area voltage to indicate tank volume. This tank volume voltage can be added to other similar outputs to indicate total system volume of a system comprising a plurality of tanks.