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41 results about "Pressure Rate" patented technology

Centrifugal compressor

According to the centrifugal compressor, a motor cavity is defined by a shell, and a plurality of pressing wheels are arranged at the two ends of a rotor shaft respectively; in the height direction of the centrifugal compressor, the first medium inlet is located in the lower end of the shell, the second medium inlet is located in the upper end of the shell, the medium outlet is located between the first medium inlet and the second medium inlet, and the first medium inlet, the second medium inlet and the medium outlet all communicate with the motor cavity. Therefore, the multiple pressing wheels are arranged at the two ends of the rotor shaft correspondingly, staged compression of gas can be achieved, the centrifugal compressor can achieve the higher pressure ratio, and the operation efficiency of the centrifugal compressor is improved; according to the centrifugal compressor, the first medium inlet is located in the lower end of the shell, the second medium inlet is located in the upper end of the shell, and the medium outlet is located between the first medium inlet and the second medium inlet, so that the flowing-in and flowing-out positions and the flowing speed of media are reasonable, the cooling effect of the centrifugal compressor can be remarkably improved, and the working performance of the centrifugal compressor is improved.
Owner:HONEYCOMB WEILING POWER TECH (JIANGSU) CO LTD

Steel slag pressure hot stuffiness rolling cooling water abnormity alarm system and method

The invention relates to the technical field of cooling water abnormity monitoring, in particular to a steel slag pressure hot stuffy rolling cooling water abnormity alarm system and method.Roll gap cooling water flow, injection temperature, hot stuffy tank pressure and bearing vibration data are collected, a dynamic mapping relation between position coordinates of a spraying opening and a water inlet valve is established, temperature and pressure time sequence offset is calculated, and the temperature and pressure time sequence offset is calculated; the temperature judgment boundary is corrected by combining the pressure bearing limit value of the sealing ring and the real-time flow, and an abnormal alarm is triggered according to the temperature over-limit frequency in the continuous time period. A multi-source analysis framework is constructed by integrating temperature, flow, pressure and vibration parameters, single-point monitoring limitation is eliminated, nonlinear influence of the flow on tank pressure is quantified by adopting a dynamic weight model, a self-adaptive temperature threshold value is generated in combination with a sealing pressure bearing limit, dynamic coupling of an alarm mechanism is realized, an abnormal scene is positioned based on time sequence analysis and coordinate mapping, and the accuracy of monitoring is improved. The sealing hidden danger is pre-judged through the thermal unbalance coefficient, and the pressure rate deviation is intercepted in real time.
Owner:NANJING IRON & STEEL CO LTD

Variably choked pressure rate-of-rise mass flow verifier

A method includes opening a flow path from a gas stick through a variable orifice, a chamber, and an outlet isolation valve of the chamber. The method further includes causing a gas to flow through the flow path at a flow rate setpoint. The method further includes actuating an opening of the variable orifice to establish a choked pressure regime within the chamber, the choked pressure regime being achieved by causing a first pressure upstream of the variable orifice to be at least two times a second pressure downstream of the variable orifice. The method further includes closing the outlet isolation valve to cause the chamber to be filled with the gas from the gas stick. The method further includes measuring a pressure rate-of-rise within the chamber. The method further includes determining one or more flow measurements based at least in part on the pressure rate-of-rise.
Owner:APPLIED MATERIALS INC

Methods for assessing a vessel with sequential physiological measurements

A method, device, and system for evaluating a vessel of a patient, and in particular the hemodynamic impact of a stenosis within the vessel of a patient. Proximal and distal pressure measurements are made using first and second instrument while the first instrument is moved longitudinally through the vessel from a first position to a second position and the second instrument remains in a fixed longitudinal position within the vessel. A series of pressure ratio values are calculated, and a pressure ratio curve is generated. One or more stepped change in the pressure ratio curve are then identified and / or located using an Automatic Step Detection (ASD) process and / or algorithm. The ASD includes identifying a general position of a starting point of the stepped change by identifying a change in the pressure ratio values within a first window along the pressure ratio curve that is at or above a first threshold change value, and identifying an optimized position of the starting point by identifying a change in the pressure ratio values within a second window along the pressure ratio curve that is at or above a second threshold change value, wherein the second window is smaller than the first window, and the second threshold change value is smaller than the first threshold change value.
Owner:BOSTON SCIENTIFIC SCIMED INC

Fuel cell system

A fuel cell system includes a system intake unit, a system exhaust unit, a fuel cell stack, an atmospheric pressure sensor, an air compressor, an airflow meter, a pressure sensor, and a control device, and prior to power generation, the air compressor is operated in a state in which an intake pipe and an exhaust pipe are connected, an exhaust pipe pressure loss map and an intake pipe pressure loss map are generated, and in power generation, an exhaust pipe pressure loss and an intake pipe pressure loss are determined by referring to the exhaust pipe pressure loss map and the intake pipe pressure loss map based on a target value of a stack flow rate, and the air compressor is controlled by a determined rotational speed for realizing the target value at the pressure ratio of the inlet pressure and the outlet pressure.
Owner:TOYOTA JIDOSHA KK

Cooling system for mobile body, mobile body with cooling system, and cooling control method

The present application aims to establish an efficient and stable cooling cycle. A cooling system for a moving body includes a compressor, a condenser, an expansion valve, an evaporator, a flow rate adjustment device that adjusts a flow rate of a cooling fluid that is guided to the condenser depending on an external environment of the moving body, an ambient temperature acquisition sensor that detects an ambient condition for acquiring an ambient temperature to which the condenser is exposed by the cooling fluid, a pressure sensor that detects a pressure of refrigerant in the condenser, a temperature sensor that detects a temperature of the refrigerant on a downstream side of the condenser, and a control unit that executes a first process of adjusting the flow rate of the cooling fluid so that the pressure of the refrigerant in the condenser is greater than a saturation pressure of the refrigerant at the ambient temperature based on an output of the ambient temperature acquisition sensor and the pressure sensor, and a second process of adjusting an opening degree of the expansion valve so that the refrigerant on the downstream side of the condenser is in a supercooled state based on an output of the pressure sensor and an output of the temperature sensor.
Owner:KAWASAKI JUKOGYO KK

Frequency conversion control method, system and logic controller for air compressor

The present application relates to the field of air compressors, and more particularly to a variable frequency control method, system, and logic controller for air compressors. The variable frequency control method for air compressors includes presetting an air compressor outlet pressure P0 and a first pressure P1 of the air compressor when the air compressor is in a stopped state; obtaining a second pressure P2 at the air compressor outlet detected by a pressure transmitter within a preset time range, wherein the second pressure P2 is the maximum pressure value within the preset time range; obtaining a pressure comparison result based on the outlet pressure P0, the first pressure P1, and the second pressure P2, and adjusting the operating frequency of the air compressor based on the pressure comparison result. The present application has the effect of making the operating state of the air compressor system more stable during operation, thereby reducing frequent speed adjustments of the equipment and increasing the service life of the equipment.
Owner:SHANGHAI RICH GAS TECH CO LTD

Overall leakage rate monitoring apparatus for containment vessel, and overall leakage rate monitoring method for containment vessel

The present application relates to an overall leakage rate monitoring apparatus for a containment vessel, and an overall leakage rate monitoring method for a containment vessel. The monitoring apparatus comprises: a flow monitoring assembly, a pressure monitoring assembly, a pressure comparison monitoring assembly, an instrument monitoring assembly and a processor, wherein the flow monitoring assembly, the pressure monitoring assembly, the pressure comparison monitoring assembly and the instrument monitoring assembly are each connected to the processor; the flow monitoring assembly is used for monitoring a depressurization flow value inside a containment vessel; the pressure monitoring assembly is used for monitoring a pressure value inside the containment vessel; the pressure comparison monitoring assembly is used for monitoring a pressure comparison value between the inside of the containment vessel and the outside of the containment vessel; the instrument monitoring assembly is used for monitoring the temperature and humidity in the containment vessel; and the processor is used for acquiring the overall leakage rate of the containment vessel on the basis of the depressurization flow value, the pressure value, the pressure comparison value, and the temperature and humidity. The method can solve the defect in an instrument configuration method for an overall leakage rate test for a containment vessel of a nuclear reactor.
Owner:CHINA NUCLEAR POWER ENGINEERING COMPANY LTD +1

Detection method and device for vehicle-mounted hydrogen storage system

The invention discloses a detection method and device for a vehicle-mounted hydrogen storage system, and the method comprises the steps: obtaining a vehicle-end hydrogen system pressure increasing rate determined by a vehicle and a station-end hydrogen system pressure increasing rate determined by a hydrogen adding machine in a hydrogen filling process, and enabling the vehicle-end hydrogen system pressure increasing rate to be used for indicating the system pressure increasing condition evaluated by the vehicle; the station end hydrogen system pressure increasing rate is used for indicating the system pressure increasing condition evaluated by the hydrogen refueling station end. Under ideal conditions, in the same hydrogen filling process, the evaluation conditions at the two ends should be almost even the same, and the two ends can be different due to leakage. Therefore, the vehicle-mounted hydrogen storage system is detected based on the pressure increasing rates of the hydrogen systems at the two ends, and a detection result used for indicating whether leakage exists in the vehicle-mounted hydrogen storage system or not in the hydrogen filling process is obtained. Whether the vehicle-mounted hydrogen storage system leaks or not is detected based on the hydrogen system pressure increasing rates determined by the vehicle end and the hydrogen refueling station end respectively in the hydrogenation process, so that the reliability of the vehicle-mounted hydrogen storage system is ensured.
Owner:WEICHAI POWER CO LTD

Jet pump process parameter design method considering gas phase and liquid phase and related products

The invention relates to the field of oil and gas production engineering, in particular to a jet pump process parameter design method considering gas and liquid phases and related products. Calculating the suction pressure of the jet pump; the minimum cavitation area of the jet pump is calculated, and multiple nozzle-throat combinations of the jet pump are determined; determining the power hydraulic pressure; calculating the flow of the power liquid, and determining the discharge pressure; calculating a dimensionless mass flow ratio; calculating a dimensionless pressure ratio; iterative calculation is carried out, and an optimal combination is obtained through screening from various nozzle-throat combinations; determining process parameters of the jet pump; determining ground pump parameters based on the process parameters of the jet pump; according to the method, the optimal operation parameters of the jet pump are determined by calculating the flow characteristics of the gas-liquid mixed fluid in the well, the accuracy of pump parameter design when the jet pump lifts the gas phase and the liquid phase can be improved, and the negative influence of the gas phase proportion on the operation performance of the pump is reduced by introducing correction calculation of the dimensionless pressure ratio and the dimensionless mass flow ratio.
Owner:PETROCHINA CO LTD

METHOD AND DEVICE FOR MEASURING GAS DIFFUSION COEFFICIENTS THROUGH POROUS MATERIALS UNDER Elevated GAS PRESSURE

Method for determining a diffusion coefficient of a diffusion of a first gas (79) through a porous material (2) into a second gas (80) at a gas pressure increased by at least 900% compared to atmospheric pressure, - wherein a sample (1) of the porous material (2) is arranged as a partition of defined thickness between a first gas space (58) and a second gas space (59), wherein the first gas space (58) is at least 5 times the size of an open pore volume of the sample (1), - wherein the first gas space (58), the open pore volume of the sample (1) and the second gas space (59) are purged with the first gas (79), - wherein the purging with the first gas (79) is completed and the first gas space (58) adjacent to the sample (1) is sealed off, - wherein the second gas (80), which is distinguishable from the first gas (79), is subsequently introduced into the second gas space (59) with a defined volume flow rate, and a gas mixture (81) comprising the second gas (80) and components of the first gas (79) is discharged from the second gas space (59), - wherein the diverted gas mixture (81) is maintained at the increased gas pressure and - wherein a concentration profile of the proportion of the first gas (79) in the gas mixture (81) derived from the second gas space (59) is recorded and analyzed with respect to the diffusion coefficient.
Owner:CLAUSTHAL UNIVERSITY OF TECHNOLOGY

Method for controlling an air pump located in a secondary air circuit

The present invention relates to a method for controlling an air pump disposed in a secondary air circuit extending between a connection on an air intake line and a connection on an exhaust line of a heat engine. The method comprises the steps of determining an initial flow rate setpoint (Dc) and pressure ratio (Crp) between the upstream and downstream sides of the air pump. It is characterized in that it comprises determining a corrected flow rate setpoint (Dc') and pressure ratio (Crp'), determining an initial control signal (Scp) of the air pump from characteristic curves (Ccp), determining a corrected control signal (Scp') from the initial control signal (Scp) of the air pump, and controlling the air pump using the corrected control signal (Scp'). Figure 6
Owner:STELLANTIS AUTO SAS

Control system for valve reliability test and control method thereof

The invention discloses a control system for a valve reliability test and a control method thereof, the control system comprises a test design subsystem, a self-checking subsystem and an automatic test subsystem, the test design subsystem is used for inputting a test target, a test piece design parameter and a test profile requirement, setting a temperature rise rate, a temperature drop rate and a pressure rate, and through FMEA analysis and comparison optimization, the automatic test subsystem is used for carrying out self-checking on the test piece design parameter and the test profile requirement; obtaining an identification and reliability combined test profile combination, and calculating a test period; the self-inspection subsystem is used for executing acquisition self-inspection, electrical self-inspection and test piece joint debugging operation, and automatically completing confirmation of the connection state of the control system and the test device and fault prompt; and the automatic test subsystem executes active valve control logic operation and check valve control logic operation based on the input of the test design subsystem so as to realize automatic operation of reliability tests of different types of valves. According to the invention, the unified control system is adapted to different types of test devices, so that the test cost is reduced, and the equipment configuration is simplified.
Owner:NUCLEAR POWER INSTITUTE OF CHINA

Energy consumption management method of multi-stage compression system based on artificial intelligence

The present invention relates to the field of electronic digital data processing technology, and specifically to an energy consumption management method for a multi-stage compression system based on artificial intelligence, including obtaining the pressure data of each hydrogen storage tank and converting it to obtain a pressure curve corresponding to each of the hydrogen storage tanks; segmenting the pressure curve to obtain a plurality of segmented interval curves; calculating the evaluation value corresponding to each of the segmented interval curves based on the pressure value change in each of the segmented interval curves; judging the current load state of each of the hydrogen storage tanks based on the evaluation value corresponding to each of the segmented interval curves; and adjusting the air intake rate of the compressor corresponding to the hydrogen storage tank according to the current load state of each of the hydrogen storage tanks. In the present invention, by monitoring the change in the pressure value of each stage of the hydrogen storage tank, the air intake rate of each stage of the compressor is calculated based on the pressure change analysis, so that the overall compression rate of the multi-stage compression system just meets the load requirements, thereby reducing energy consumption.
Owner:BEIJING XINGYI SPACE TECH CO LTD

Reticle load lock system and method

A reticle load lock with a variable size orifice valve or with a servo valve control is described. The servo valve control can continuously adjust the size of the orifice so that the reticle load lock can be pumped or vented at an optimal level. The servo valve control pressure curve follows an optimized pressure rate to protect the integrity of the pellicle structure. The optimized servo valve control curve minimizes the pump down and vent time without exceeding the pressure rate (dP / dt) limit. By following the optimized pressure rate curve, the servo valve control significantly reduces the time to pump down and vent and prevents the pellicle from rupturing.
Owner:ASML NETHERLANDS BV

A forging method for improving the uniformity of the microstructure of large-sized TiZrNb high-entropy alloys

ActiveCN118835181BHigh entropy alloysIngot
The present invention relates to a forging method for improving the uniformity of the structure of a large-size TiZrNb-based high-entropy alloy, and belongs to the technical field of alloys. First, the TiZrNb-based high-entropy alloy ingot is heated, and then the first fire forging is performed, and the forging temperature, deformation amount and pressing rate are controlled throughout; then, the second and third fire forgings are performed again, and finally recrystallization annealing is performed. The TiZrNb-based alloy forged by the method has increased uniformity of the structure, obtained refined grains, and improved shrinkage and shrinkage cavities generated by casting, which can avoid the generation of defects such as cracks, and achieve the matching of alloy strength and plasticity.
Owner:BEIJING INST OF TECH

Micro-flow three-gas mixing control structure with quick and stable response

The utility model provides a micro-flow three-gas mixing control structure which is quick and stable in response, and belongs to the technical field of gas flow control. The micro-flow three-gas mixing control structure rapid and stable in response comprises a high-pressure stabilizing valve body assembly and a gas converging assembly. The first gas valve terminal assembly comprises a first gas valve terminal valve body, an electromagnetic valve and a high-precision gas resistor, the gas outlet end of the first gas valve terminal valve body is connected with the gas inlet end of the electromagnetic valve, the gas outlet end of the electromagnetic valve is connected with the gas inlet end of the high-precision gas resistor, and the gas inlet end of the first gas valve terminal valve body is communicated with a proportional valve; the pressure of the high-pressure gas is reduced to a proper pressure through the pressure reducing valve, the proportional valve plays a role in stabilizing the pressure of the gas flow, and then the flow is controlled by permutation and combination of different high-precision gas resistors, so that the flow is accurately controlled from small to large. Stable and accurate control of micro flow and rapid response of micro flow change are achieved.
Owner:BEIJING ETERNITY ELECTRONICS TECH

Valve control system and method

A sprayer control system includes a plurality of smart nozzles each having at least one control valve with a valve operator, an electronic control unit for the valve operator, and one or more spray nozzles. The at least one control valve and the ECU control a flow rate of liquid agricultural product through the nozzles. A duty cycle modulator is in communication with the ECU and generates an applied duty cycle for the at least one control valve. The duty cycle modulator includes a specified duty cycle input having a specified duty cycle and a pressure monitor associated with the at least one control valve. A pressure comparator compares the valve pressure determined with the pressure monitor with a system pressure and generates a pressure error. An applied duty cycle generator generates the applied duty cycle based on the specified duty cycle modified by the pressure error.
Owner:RAVEN INDUSTRIES INC

Monitoring effectiveness of support pulses for extracorporeal circulation support

The invention relates to a method for monitoring cardiac cycle synchronized extracorporeal circulation support and to a corresponding device and circulation support device, in particular for optimizing the provided support pulses. Accordingly, a method for monitoring cardiac cycle synchronized extracorporeal circulation support (12) of a patient is described, comprising the steps of: receiving a pressure value characterizing an aortic pressure of the supported patient; determining a first minimum pressure value (40) of the cardiac cycle of the patient and a first point in time of the minimum pressure value (40) from the pressure values; determining, from the pressure value, whether there is a reduced rate of change of pressure at a subsequent second point in time (42), the reduced rate of change of pressure lying between an immediately preceding greater rate of change of pressure and a subsequent greater rate of change of pressure; and outputting a signal as a function of the reduced rate of pressure change (42) present. The pressure value is received by a pressure sensor (32) arranged upstream of an arterial cannula (30) of an extracorporeal circulation support (12) and downstream of an oxygenator (28).
Owner:XENIOS AG

Intelligent cruising method and system for pressure change rate of thermal power generating unit

The invention relates to the technical field of thermal power generating units, in particular to an intelligent cruising method and system for the pressure change rate of a thermal power generating unit. The method comprises the following steps: acquiring key parameters of thermal power generating unit operation in real time; the sliding pressure rate is adjusted in a staged mode, and control logic is set; according to the key parameters and the control logic, the sliding pressure rate is adjusted, closed-loop dynamic adjustment is formed, the sliding pressure rate can be automatically adjusted, closed-loop dynamic adjustment of the sliding pressure rate is achieved, unit parameter fluctuation is reduced, stable operation of a unit is guaranteed, and meanwhile the operation amount of operators is reduced.
Owner:XIAN THERMAL POWER RES INST CO LTD +1

Pressure data processing method, device, equipment and storage medium

The present invention provides a pressure data processing method, device, equipment and storage medium, including: obtaining real-time pressure data obtained by real-time pressure detection of a variable stiffness load of a motor; comparing the real-time pressure data with preset target pressure data to obtain pressure comparison data, the pressure comparison data including pressure deviation and pressure deviation change rate; performing fuzzy control decision on the pressure comparison data according to preset fuzzy control rules to obtain a fuzzy subset, wherein the fuzzy control rule includes a correspondence between different pressure ranges and different load stiffness ranges; performing defuzzification processing on the fuzzy subset using a set defuzzification algorithm to obtain a pressure control quantity, so as to perform closed-loop control of the output pressure of the motor according to the pressure control quantity. The technical solution of the present invention can obtain a better motor control effect under variable stiffness load conditions.
Owner:TSINGHUA UNIVERSITY

System and procedure for controlling a vehicle's fuel cell

Method for controlling a fuel cell (100) of a vehicle, comprising: Determine by means of a control whether pressure regulation is required to exert pressure on air being discharged from an air supply device (200), based on whether additional power output from the fuel cell (100) is required or whether the fuel cell (100) is in a drying-out state; In response to the determination that pressure control is required, deriving an opening degree of a valve on one side of an air outlet of the fuel cell (100) required for pressure control, by controlling and adjusting the valve based on the derived opening degree of the valve; Calculating a pressure ratio by the controller, which is obtained by calculating the following: (current degree of opening - first degree of opening) / (second degree of opening - first degree of opening), wherein the current degree of opening is a valve opening degree at the present time, the first degree of opening is an opening degree required when an air pressure is atmospheric pressure, and the second degree of opening is an opening degree at a time when the pressure regulation is complete; and Increasing a target hydrogen pressure based on an increase in the calculated pressure ratio or an increase in the flow rate of the air discharged from the air supply device (200).
Owner:HYUNDAI MOTOR CO LTD +1

Method for regulating boost pressure in power machinery

This invention relates to a method for regulating the boost pressure of a power machine, wherein the power machine has a boosting device with a compressor and a compressor bypass, wherein the compressor bypass has a propulsion recirculation air valve for opening and closing the compressor bypass, wherein the boost pressure regulation uses the actual boost pressure and the rated boost pressure as input parameters, wherein a first compressor pressure ratio is determined based on a limit line from the compressor characteristic curve and the engine absorption line of the power machine, and a second compressor pressure ratio is determined based on a limit line from the compressor characteristic curve, the mass flow rate through the power machine, and a throttling characteristic line for the propulsion recirculation air valve, wherein a maximum permissible compression ratio for the compressor is determined from the first and second compressor pressure ratios, wherein a maximum permissible boost pressure is determined based on the maximum permissible compression ratio, and wherein the boost pressure regulation is limited to this maximum permissible boost pressure.
Owner:ROBERT BOSCH GMBH

Unmanned aerial vehicle flight control brake instruction control method

The invention discloses an unmanned aerial vehicle flight control brake instruction control method, and belongs to the technical field of aircraft brake control. Firstly, a step instruction is applied in the initial stage of braking, the current pressure efficiency is observed through the wheel speed variation, and the braking capacity is quantified; secondly, the pressurization rate is determined according to the pressure efficiency, a brake instruction is continuously increased, the speed reduction rate change rate is monitored, when the speed reduction rate change rate approaches zero, it is judged that the moment balance state is reached, and the speed reduction rate at the moment is determined as the target speed reduction rate; and finally, dynamically adjusting a brake instruction by taking the target deceleration rate as a reference to realize state tracking. According to the invention, closed-loop control of target deceleration rate detection and target deceleration rate tracking is realized only by depending on the wheel speed signal, the braking efficiency is effectively improved, overshoot is inhibited, and the method has the advantages of simple engineering realization, strong adaptability and good robustness.
Owner:XIAN AVIATION BRAKE TECH

Front wheel pressure adjustment method, device and storage medium

The embodiment of the present invention discloses a front wheel pressure regulation method, device and storage medium. The front wheel pressure regulation method comprises: obtaining a brake pedal stroke signal; determining the front wheel pressure state according to the brake pedal stroke signal; adjusting the opening of the front wheel inlet valve or maintaining the opening of the front wheel inlet valve according to the front wheel pressure state to control the front wheel boost rate. This solution can reduce the boost rate of the front wheel by adjusting the opening of the front wheel inlet valve, prevent the front wheel pressure from reaching the locking critical point quickly, and prevent the front wheel from entering the locking state quickly, thereby reducing the braking distance and enhancing the safety of vehicle braking to a certain extent. In addition, by adjusting the opening of the front wheel inlet valve to reduce the front wheel boost rate, the vehicle's powertrain suspension can be prevented from hitting the limit, avoiding collision noise and collision vibration inside the vehicle, and ensuring the comfort of the vehicle to a certain extent.
Owner:CHINA FAW CO LTD

Hydrogen regulator with damping structure

The present invention relates to a hydrogen regulator, comprising: an upper chamber (50) in which a constant internal pressure is generated by compressed air; a lower chamber (60) connected to the upper chamber (50) through an orifice structure, in which a relief valve is configured in an intermediate region between the upper chamber (50) and the lower chamber (60) connected by the orifice structure so that the internal pressures of the two chambers are maintained at a constant pressure ratio, thereby providing a constant buffering force proportional to the pressure of a low-pressure output unit (30) during a vertical movement of a pressure control spring (40) for pressure control, thereby enabling a stable constant pressure output even under rapid pressure fluctuations and ensuring that the pressure inside the upper chamber (50) is maintained constant. Accordingly, the present invention has the effect that, when pressure is controlled by the hydrogen regulator, the output pressure of a fluid can be maintained constant even when abrupt pressure changes occur.
Owner:BUCKLEY MASCHOFF & TALWALKAR LLC

Systems and methods for providing surge relief

The present disclosure pertains to a system configured to protect flows in piping systems using minimal spare components. Some embodiments may provide: a first piping subsystem configured to receive a portion of the input flow; a second piping subsystem configured to receive the portion of the input flow by substituting for the first subsystem; a test subsystem configured to detect whether each of the first and second subsystems is able to vent when at least one, in the each subsystem, of a respective pressure and a respective pressure rate satisfies first and second criteria, respectively; and first and second pilots configured to detect a maximum pressure and a maximum pressure rate, respectively, of the portion of the first and second subsystems.
Owner:CELEROS FLOW TECHNOLOGY LLC

Reticle load lock system and method

A reticle load lock having a valve with a variable size orifice, or servo valving, is described. Servo valving can continually adjust the size of the orifice such that the reticle load lock can pump or vent at an optimal level. The servo valving pressure profile follows an optimized pressure rate to protect the structural integrity of the pellicle. The optimized servo valving curves minimize the evacuation and vent times without exceeding the pressure rate (dP / dt) limits. By following the optimized pressure rate curve, servo valving significantly reduces the time to pump down and vent and prevents breakage of the pellicle.
Owner:ASML NETHERLANDS BV

Method and device for adjusting main steam pressure of thermal power generating unit

The invention discloses a method and device for adjusting the main steam pressure of a thermal power generating unit. The method comprises the steps that a target pressure value and a target main steam design temperature value corresponding to a target thermal power generating unit are determined according to a current load corresponding to the target thermal power generating unit; acquiring a current actual main steam temperature value and a current pressure value corresponding to the target thermal power generating unit; determining a sliding pressure rate correction coefficient according to the target main steam design temperature value and the current actual main steam temperature value, and correcting the preset sliding pressure rate according to the sliding pressure rate correction coefficient to obtain a corrected sliding pressure rate; and main steam pressure corresponding to the target thermal power generating unit is adjusted according to the corrected sliding pressure rate, the target pressure value and the current pressure value.
Owner:NORTH CHINA ELECTRICAL POWER RES INST +1

Variably choked pressure rate-of-rise mass flow verifier

A method includes opening a flow path from a gas stick through a variable orifice, a chamber, and an outlet isolation valve of the chamber. The method further includes causing a gas to flow through the flow path at a flow rate setpoint. The method further includes actuating an opening of the variable orifice to establish a choked pressure regime within the chamber, the choked pressure regime being achieved by causing a first pressure upstream of the variable orifice to be at least two times a second pressure downstream of the variable orifice. The method further includes closing the outlet isolation valve to cause the chamber to be filled with the gas from the gas stick. The method further includes measuring a pressure rate-of-rise within the chamber. The method further includes determining one or more flow measurements based at least in part on the pressure rate-of-rise.
Owner:APPLIED MATERIALS INC