1066 results about "Electromagnetic flowmeter" patented technology

An electromagnetic flowmeter assembly is described in which an excitation field is set up across a flow conduit and electrodes are used to sense the electromagnetic field generated across the flow conduit as a result of interaction between the excitation field and fluid flowing along the flow conduit. The signals obtained from the electrodes are processed, together with stored calibration data, by processing circuitry to determine flow measurements and means is provided for dynamically updating the calibration data.

The invention discloses a DSP-based electromagnetic flowmeter signal processing system, which comprises a hardware system and a software system. The hardware system consists of an excitation driving module, a signal modulation and acquisition module, a signal processing control module, a man-machine interface module, a communication module and a power supply management module. The signal control module uses DSP as a core. In the system, a high frequency square wave excitation control scheme is adopted, and the DSP generates an excitation time sequence to control the excitation driving module to perform high frequency square wave excitation of a magnet exciting coil; the signal modulation and acquisition module amplifies and filters an output signal of an electromagnetic flowmeter, performs the analog-to-digital conversion of the output signal and outputs the output signal to the DSP; the software system processes an acquired signal to obtain a flowmeter measurement result and send the result to a liquid crystal display; and the parameters of the flowmeter are set by keyboard operation or by the interaction between a master computer and the flowmeter by the communication module. The system can realize the high-accuracy and high-speed measurement of fluid flow, particularly the measurement of flow of liquid-solid two-phase fluid such as pulp.

An improvement over conventional electromagnetic flowmeters which signal a measure of flow rate by controlling the current in a current signalling loop (also known as a sensing loop) and in which power for the flowmeter is derived from the current in the signalling/sensing loop. Conventional electromagnetic flowmeters use a standard current range (typically 4-20 mA), in which zero flow is indicated by controlling the current in the loop to a minimum predeterimened value and maximum flow is indicated by controlling the current to a maximum predetermined value. In the improved flowmeter of the invention, minimum flow is signalled by maximum current in the signalling/sensing loop and maximum flow is signalled by minimum current. This has been found to enable improved accuracy to be obtained at low flow rates without requiring complex flowmeter circuitry.

The invention discloses a testing device and a testing method for a three-dimensional PIV (Particle Image Velocimetry) internal flow field testing system of a hydraulic retarder. The testing device comprises a driving motor, a transmission case, a pneumatic clutch, a flywheel case, a torsion and rotating speed sensor, a braking shaft, a visualized hydraulic retarder, a visualized testing chamber, a circular guide rail, a synchronizer, a double-pulse laser, CCD (Charge Coupled Device) cameras, a water storage tank, a water pump, a pressure inductor, a pressure reducer, a particle dispenser, an electromagnetic flowmeter and the like; the visualized testing chamber is made of a transparent material and is suitable for an aqueous medium; the braking shaft is driven by an external driving system, is supported by a bearing, passes through a shell of the hydraulic retarder and is connected with a driving wheel of the retarder; the first CCD camera is arranged at the top of the visualized testing chamber and is used for shooting downwards; the second CCD camera and the double-pulse laser are arranged on the circular guide rail and can arbitrarily rotate along the guide rail; and the circular guide rail and the visualized testing chamber are respectively fixed on the base. The testing device and the method disclosed by the invention can be used for carrying out three-dimensional PIV measurement on the internal flow field of the hydraulic retarder and is simple and compact in structure, good in universality and easy to control.

The invention discloses a simulation test system integrating the start, movement and accumulation of debris flow, including an instrument table, a water supply system, a control center, a pipeline and a water distribution system, a receiving line, an electromagnetic flowmeter, a water guide pipe, and a raindrop simulation system. Sprinklers, rain sensors, source tanks, porometers, matrix suction probes, soil moisture probes, flow tanks, flow rate test devices, impact test devices, stacking plates, tailing tanks, lifting systems and digital acquisition systems. The invention can combine the two types of mud-rock flow caused by rainfall and water erosion for research, and simulate the real rainfall process; it can effectively monitor the key parameters in the mud-rock flow experiment process, and simulate the whole process of mud-rock flow initiation, migration and accumulation.

The invention relates to a mono-dual frequency electromagnetic flowmeter excitation control system based on linear power supply, comprising a constant current source circuit, a current bypass circuit,an exciting coil driving circuit, an excitation time sequence generating circuit and a galvo circuit. A high voltage power supply is adopted for supplying power, the constant current source is constructed by linear power supply to supplying electricity for the exciting coil driving circuit, the current bypass circuit is jointed in parallel with the input/output end of the linear power supply to solve the problem of energy dissipation, the exciting coil driving circuit is composed of an H bridge and a control circuit thereof, the galvo circuit is bridge-jointed between the lower end of the H bridge and a reference ground, and a digital signal processor (DSP) is used for controlling multiple switches and an electrical level matching device to generate time sequence and control the action ofthe exciting coil driving circuit. The excitation control system can obviously improve excitation frequency range and excitation frequency preciseness, is suitable for single frequency high frequencysquare wave excitation or dual frequency square wave excitation, and can simultaneously provide more exact current detection to correct the flow signal processing result.

The invention relates to a high/low voltage switching excitation system of an electromagnetic flowmeter with a bypass and an energy feedback circuit. The excitation system comprises an adjustable low voltage source circuit, a high/low voltage switching circuit, a constant-current circuit, a bypass circuit, an H-bridge excitation circuit, an excitation control circuit, a logic switching circuit, apower supply detection circuit, the energy feedback circuit and an energy leakage circuit. A practical excitation current detected on a current detecting resistor is compared with an excitation current threshold set in the logic switching circuit, thereby obtaining a control logic which is used for controlling the high/low voltage switching circuit and the bypass circuit, so as to select an excitation work voltage; introduction of the bypass circuit accelerates the response velocity of the excitation current in a coil obviously; the energy feedback circuit stores the energy fed back from an excitation coil; the power supply detection circuit, the energy leakage circuit and a switching protection circuit perform electrification, outage and error protection on the excitation system. The excitation system related to the invention improves the utilization rate of power supply, accelerates the response speed of excitation current, broadens the range of excitation frequency and provides circuit fault protection.

The invention relates to a multiphase flow erosion local corrosion testing apparatus. The testing apparatus comprises an ore pulp pump, a slurry tank, a stirrer, a pressure gage, an electromagnetic flowmeter, a pipe flow erosion pipe section, a jet flow erosion pipe section, a thermocouple and a low temperature constant temperature circulator. The testing apparatus is characterized in that the stirrer is arranged above the slurry tank, the thermocouple is mounted in the slurry tank and is connected with the low temperature constant temperature circulator, the bottom end of the slurry tank is connected with the ore pulp pump through a feed pipe, a ball valve is installed on the feed pipe, an outlet pipe of the ore pulp pump is provided with a first stop valve and is divided into two paths through the stop valve, one path returns to the slurry tank after passing through a second stop valve, and the other path returns to the slurry tank after passing through the pressure gage, the electromagnetic flowmeter, the pipe flow erosion pipe section and the jet flow erosion pipe section. According to the invention, characteristics of pipe flow and jet flow erosion-corrosion testing machines are combined, pipe flow erosion and jet flow erosion local corrosion tests can be simultaneously or individually carried out, and the testing apparatus has the characteristics of a small size, a simple structure, low manufacturing cost and good operationality.

The invention discloses a liquid metal sodium boiling two-phase thermal-hydraulic test loop system and a test method thereof. The loop system is divided into three parts comprising a high temperature part, a low temperature part and an argon branch, wherein the low temperature part comprises a sodium storage tank, an electromagnetic pump, an electromagnetic flowmeter, a purification cold trap, four sodium valves and corresponding connecting pipelines; the low temperature part is made of 316L stainless steel; the high temperature part comprises a regeneration heater, a preheater, a test section, an upper expansion box and corresponding connecting pipelines; the high temperature part is made of Incoloy 800 and allows the operating temperature to reach 1,200 DEG C; and the argon branch comprises an argon bottle, an expansion pressure stabilizing box, a vacuum pump, three pressure gauges, ten vacuum diaphragm valves and corresponding connecting pipelines. The system is suitable for operating at high temperature, has a good sealing property and can realize analysis and research on the liquid metal sodium boiling two-phase heat exchange flow characteristic by adding different test sections and a data acquisition system.

The invention discloses a multi-electrode electromagnetic flow meter and relates to the technology field of measurement. The flow meter comprises six electrodes arranged on the circular cross-section of a sensor conduit, the sensor conduit is perpendicular to the central axis of the conduit, wherein, four electrodes are measuring electrodes that are symmetrical about the X-axis and the Y-axis of the circular cross-section, and two electrodes are liquid collecting electrodes. Two measuring electrodes are in a group, the two liquid collecting electrodes are arranged between the two groups of measuring electrodes. The two measuring electrodes in a group are reliably connected. The two groups of measuring electrodes are respectively connected with a converter and an amplifier. The two liquid collecting electrodes are reliably connected and then connected to the metal of a measuring conduit, and serve as the basis ground of flow signals for connecting the ground terminal of the converter and the amplifier. The multi-electrode electromagnetic flow meter is characterized by small additive measuring error, convenient assembly and reliable liquid collecting reference, and can provide the reliable ground reference electrical potential.

A magnetic flowmeter transmitter includes a differential amplifier that senses an additive combination of actual flowmeter electrode outputs and simulated electrode outputs. The differential amplifier provides an additive amplifier output. A simulator provides the simulated electrode outputs. The simulator senses the additive amplifier output and provides an error indication when the additive amplifier output is outside a normal range.

An electromagnetic flowmeter for measuring a flow rate of a fluid in a pipe is described. A pipe carries a fluid. A magnetic coil is disposed adjacent to the pipe for inducing a magnetic flux in the fluid. A plurality of electrodes are disposed within the pipe, and the plurality of electrodes are electrically isolated from one another. Measurement circuitry is coupled to at least one of the plurality of electrodes and is configured to measure flow rate as a function of a potential across the plurality of electrodes. An empty pipe detector is coupled to at least one of the plurality of electrodes and is adapted to detect an empty pipe condition based upon an adjustable test criteria. In one embodiment, a local operator interface is coupled to the empty pipe detector for adjusting the adjustable test criteria.

An electromagnetic flow meter has a pipe body 16 in which a measurement target fluid flows. The pipe body 16 includes: a measurement pipe 1 having a groove 3 whose cross-section is any of a semicircular shape, a rectangular shape, and a triangular shape formed on an inner surface in a circumferential direction; and a resin lining portion 10a formed on the inner surface of the measurement pipe.

The invention is a method of testing and regulating oil-field layered injected water flow, and its characteristic: putting down flow testing and regulating meter to butt with regulable flow stopper in the deviation hole of an eccentric water distributor, and then measure the actual flow by an electromagnetic flowmeter in the flow testing and regulating meter and then sending the measured result through the cable to a ground control system, comparing the measured signal with the water injection set signal for the layer by the ground control system: if they do not tally with each other, it sends a control instrument to regulate water injection to the flow testing and regulating meter to drive a regulating rod on the flow stopper for regulating the size of water outlet by the butt joint, and then achieving the purpose of regulating water injection. The invention has the characters of high testing precision and short time for testing and regulating.

An electromagnetic flowmeter with voltage-amplitude conductivity-sensing function for a liquid in a tube includes a first microprocessor, a transducer, flow-sensing device, an exciting-current generating device, a voltage-amplitude conductivity-sensing device, and a switch. The transducer includes coils and sensing electrodes. The switch is electrically connected to the first microprocessor and the sensing electrode. The switch is selectively connected to the flow-sensing device or the voltage-amplitude conductivity-sensing device according to the signals sent from the microprocessor. The microprocessor makes the exciting-current generating device to generate an exciting current when the switch is connected to the flow-sensing device. The microprocessor makes the exciting-current generating device to stop generating exciting current and computing conductivity of liquid when the switch is electrically connected to the voltage-amplitude conductivity-sensing device.

The invention relates to an ultrafast cooling device for large rolled H-shaped steel, belonging to the technical field of production control and cooling for high-performance H-shaped steel.The invention provides a ultrafast cooling device for large rolled H-shaped steel, which can enable the H-shaped steel to obtain good texture and mechanical property.The cooling device comprises a rail support of a transverse rail, which is fixed at the upper part of the device, a cooling unit provided with a cooling rack, which is arranged on the transverse rail and a transverse roller wheel which is arranged below the cooling rack; wherein the cooling unit comprises a lateral nozzle unit, an upper nozzle unit and a side board provided with a groove; the side board is arranged on the cooling rack, a lateral nozzle tank body is fixed outside the side board; and an upper nozzle unit is arranged above the inside of the side board, a lower nozzle unit is arranged on a motor base of a conveying rail, the lower nozzle unit is connected with a water supply pipe; an electromagnetic flowmeter, a pressure sensor and a pneumatic open and close valve are respectively on the water supply pipe and thermodetectors are respectively arranged at the entrance and exit of the ultrafast cooling device.

An electromagnetic flowmeter includes a coil, exciting section, noise eliminating section, and arithmetic processing section. The coil applies a magnetic field to a fluid flowing in a pipe line. The exciting section supplies an exciting current to the coil. The noise eliminating section eliminates noise from a measurement signal detected from the fluid under excitation by using a differential frequency component between a commercial power frequency and an exciting frequency. The arithmetic processing section calculates a measurement flow rate on the basis of the measurement signal output from the noise eliminating section.

The invention discloses a capacitive electromagnetic flow signal converter. Two E-shaped magnetic yokes are adopted and are combined together face to face at the position of an opening so as to form a closed loop, and therefore working magnetic field leakage can be effectively prevented. Meanwhile, according to the two E-shaped magnetic yokes which are formed by stacking E-shaped silicon steel sheets, excitation coils are wound on stretching-out portions in the middles of the E-shaped magnetic yokes, two Helmholtz coils are connected in series and arranged coaxially, and the Helmholtz coils are identical in shape, size and number of turns. After excitation signals are input into the Helmholtz coils which are connected in series, an even working magnetic field with the magnetic field intensity changing along with excitation sinusoidal signals can be generated between excitation devices, due to the fact that the generated working magnetic field is even, the magnetic permeability of the silicon steel sheets is very good, the magnetic field at the position of a measuring pipe is very strong, the sensitivity of flow detection is also improved, so that fluid flow can be effectively converted into electric signals to be output, and the fluid flow measuring accuracy of a capacitive electromagnetic flow meter is further improved.

The invention discloses an automatic start-stop and exposure intensity control ultraviolet disinfection device. The disinfection device mainly comprises an electromagnetic flowmeter, a water quality instrument, an ultraviolet sterilizer, ultraviolet lamp tubes, a controller, a water inlet pipe, a sensor and a water outlet pipe. Water flows through the water inlet pipe to penetrate through the electromagnetic flowmeter and then flows into the ultraviolet sterilizer through the water quality instrument, the ultraviolet sterilizer includes the ultraviolet lamp tubes, the sensor is installed on the water outlet pipe, and the controller is connected with the electromagnetic flowmeter and the sensor through leads. The disinfection device can achieve automatic ultraviolet sterilizer starting and stopping functions when water flows and stops, meanwhile can also control ultraviolet light exposure intensity according to water flow and water quality characteristics, accordingly can more intelligently water disinfection and can further play an energy-saving effect.