71 results about "Pressure decay" patented technology

The invention relates to the technical field of workpiece airtightness detection, in particular to a workpiece airtightness detection method and system based on multi-source data fusion, and the method comprises the steps: collecting the pressure fluctuation, temperature field distribution and vibration spectrum data of a workpiece through a sensor array, and executing a stepped pressure excitation process; the method comprises the following steps: dynamically configuring an inflation rate according to the heat-conducting property of a material, reversely compensating pressure based on temperature field data in a pressure maintaining stage to eliminate thermal deformation interference, and extracting a pressure attenuation rate and nonlinear characteristics, an area proportion of an abnormal low-temperature region and space aggregation of an energy abrupt change point in a vibration spectrum from compensated data; according to the method, multi-physical field features are fused, the detection precision and reliability are improved, and the method is suitable for the airtightness detection requirement in the high-precision manufacturing field.

The invention relates to the technical field of measurement and testing, in particular to a leakage detection method and system for transformer oil tank production, and the method comprises the steps: dividing a to-be-detected oil tank into a plurality of test regions; determining an ideal net pressure attenuation rate by using the average pressure drop rate, the pressure change rate corresponding to the temperature change and the volume change amount of the oil tank cavity in the target time period in the target test area; determining a pressure attenuation deviation degree by using the ideal net pressure attenuation rate and the actually measured net pressure attenuation rate; determining an acoustic activity weight by using the acoustic activity degree of the acoustic signal in the acoustic event and the background noise average energy of the plurality of test areas in the acoustic event; and determining a regional leakage comprehensive index by using the acoustic activity weight and the pressure attenuation deviation degree, and further determining the leakage detection condition of the oil tank by using the regional leakage comprehensive index. According to the technical scheme, the accuracy and reliability of leakage detection are effectively improved, environment temperature interference is effectively eliminated, and background noise changes are dynamically adapted.

The invention provides an inflator pump air tightness detection method and system based on TPMS feedback and flow modeling, and the method comprises the steps: obtaining a real-time pressure fluctuation signal and an instantaneous flow fluctuation waveform of an inflator pump gas conveying pipeline, and extracting a corresponding relation between a continuous change rule of a pressure gradient and a flow peak appearance moment; on the basis of the corresponding relation and a three-dimensional structure model of a sealed cavity in the inflator pump, pressure gradient spatial and temporal distribution and flow peak spatial and temporal distribution in the gas flowing process are reconstructed, the flowing track of gas in a pipeline is traced, and the spatial mapping relation between a flow abnormal fluctuation area and a pressure attenuation change area is recognized; and comparing the gas flow path with a gas flow path in a standard sealing state, positioning a key node of sealing failure in combination with a space mapping relationship, and determining the quantification level of the air tightness defect of the inflator pump according to the abnormal change degree of the key node and in combination with the distribution characteristics and mutual influence of the plurality of key nodes. According to the invention, the accuracy and reliability of air tightness detection are effectively improved.

The invention relates to the technical field of active protection systems of hydraulic servo systems, and discloses an active protection system of a hydraulic servo system, which comprises an overload protection module, a temperature control module, a leakage monitoring module, a vibration suppression module, a redundancy design module and an intelligent control module, the overload protection module comprises a pressure sensor and a servo valve current limiting structure, the temperature control module comprises an oil temperature sensor and a self-adaptive cooling system, the leakage monitoring module comprises a flow meter and a pressure attenuation monitoring unit, and the vibration suppression module comprises an acceleration sensor and an active damping servo valve. The redundancy design module comprises a double-servo-valve parallel structure and double hydraulic pump sets. The intelligent control module comprises a fault diagnosis unit and a dynamic parameter compensation unit. Through the system, a multi-dimensional active protection system can be formed, and the safety, reliability and stability of the hydraulic servo system are improved.

The invention relates to the technical field of intelligent control and predictive maintenance of heating water heaters, in particular to a wind pressure switch control system and method for a heating water heater. The method comprises the following steps of: extracting a starting pressure curve slope, a steady-state pressure fluctuation frequency spectrum entropy and a shutdown pressure decay time constant by collecting a time sequence pressure signal in a working period of a fan so as to generate a dynamic feature vector; comparing the vector with a preset reference health vector by the system, and resolving the health state confidence and the state deviation drift rate of the system in real time; when the health confidence coefficient is lower than a safety threshold value or the deviation drift rate is too high, the system executes forced safety locking; if the health degree is slightly reduced, the pre-purging time of the fan is actively prolonged as compensation; according to the method, conversion from fault response to predictive maintenance is achieved, early performance degradation symptoms such as fan abrasion and air duct dust deposition can be recognized in advance, post-maintenance is converted into beforehand intervention, and the fault rate and maintenance cost are effectively reduced.

The invention discloses a motorcycle ABS performance detection method, system and device and a medium, and relates to motorcycle ABS detection. According to the method, the brake fluid is subjected to dewatering and degassing treatment, and target brake fluid is obtained; establishing an instruction transmission channel; the brake pipeline is subjected to air exhaust operation, and the negative pressure establishment rate and the dwell pressure attenuation rate are measured; judging whether the sealing performance of the brake pipeline reaches the standard or not; if the sealing performance reaches the standard, target brake fluid is injected into the hydraulic loop in an excessive injection mode of the preset target liquid level amount, and after injection is completed, the target brake fluid is controlled to reach the preset liquid level height through a back suction device; and a brake pressure release instruction is sent to the hydraulic device through the instruction transmission channel, and after the hydraulic device drives the brake device to complete brake operation of a preset number of rounds according to the brake pressure release instruction, a detection result is obtained according to the position change of the brake device. By implementing the scheme, the performance of the ABS system can be effectively detected, and the ABS system can be effectively controlled.

A self-validated mass flow control (MFC) apparatus and a method of providing self-validated mass flow control are provided. The MFC includes a chamber configured to receive a fluid, an upstream valve disposed upstream of the chamber, and a downstream control valve disposed downstream of the chamber. The MFC further includes a pressure drop assembly disposed downstream of the downstream control valve, and first and second pressure sensors. A controller of the MFC is configured to control actuation of the downstream control valve by switching between a flow-based feedback control and a pressure-based feedback control. In the flow-based feedback control, the flow is monitored based on a rate of pressure decay in the chamber detected by the first pressure sensor when the upstream control valve is closed. In pressure-based feedback control, the pressure upstream of the pressure drop assembly detected by the second pressure sensor is monitored.

The application discloses a kind of mine roadway surrounding rock fissure rock mass bearing capacity detection equipment with drilling, and the application relates to the technical field of coal mine drilling survey, including drill rod, one end of the drill rod is provided with comprehensive drilling bit, water inlet pipe is arranged in the drill rod, and the water inlet pipe is used to supply water to the inside of comprehensive drilling bit, the inside of the drill rod is also provided with detection mechanism, the detection mechanism includes: pressure storage tank, one side of the pressure storage tank is fixedly connected with first connecting pipe, the first connecting pipe is fixedly connected with the output end of water pump at the end away from the pressure storage tank, the present application is provided with pressure detection module, flow rate detection module and high-frequency dynamic pressure sensing module, and combined with multi-parameter synchronous acquisition and coupling analysis, the pressure decay characteristic, flow change characteristic and transient pressure response characteristic can be obtained simultaneously, so as to construct surrounding rock fissure equivalent permeation response parameter, with the advantages of realizing the continuous acquisition of surrounding rock fissure permeation characteristic and its spatial distribution.

The present application relates to the field of measurement and testing, and relates to a kind of leakage detection method and system for transformer oil tank production, comprising: the oil tank to be measured is divided into multiple test areas;The pressure drop average rate of oil tank cavity in target time period, the pressure change rate corresponding to temperature change of target test area and the volume change amount are used to determine ideal net pressure decay rate;Ideal net pressure decay rate and measured net pressure decay rate are used to determine pressure decay deviation;The acoustic activity degree of acoustic signal in acoustic event and the background noise average energy of multiple test areas in the acoustic event are used to determine acoustic activity weight;Acoustic activity weight, pressure decay deviation are used to determine regional leakage comprehensive index, and then the leakage detection condition of oil tank is determined using regional leakage comprehensive index;The technical scheme of the present application effectively improves the accuracy and reliability of leakage detection, effectively eliminates environmental temperature interference and dynamically adapts to background noise change.

The application discloses a kind of gas insulated switchgear gas chamber pressure leakage degree judging method and system, applied to insulating switchgear gas chamber detection technical field, method includes first obtaining the pressure value of the gas chamber to be evaluated in preset time period, constructs pressure value sequence, and then the sequence is weighted average processing, obtains first final pressure value sequence, again to first final pressure value sequence Pressure mutation identification, locates pressure mutation interval and removes it, obtains second final pressure value sequence.Then, construct pressure state space model, input model to predict second final pressure value sequence, obtain optimal estimation pressure value sequence, calculate pressure decay rate according to optimal estimation pressure value sequence, and the pressure decay rate is segmented linear transformation, finally output gas chamber pressure leakage severity value.Through the above method, the accuracy of pressure leakage evaluation is effectively improved.

A method for determining properties of hydraulic fractures from measurements of pressure in a well made after stopping pumping fracturing fluid into the well (shut in) includes determining a first time after shut in whereinafter a decrease in measured pressure is caused by fluid leak off in a fracture. A second time after shut in is determined whereinafter the decrease in pressure is caused by fluid leak off, fracture growth and fluid pressure equilibration in the fracture. A third time after shut in is determined whereinafter the decrease in pressure is caused by fluid leak off, fracture growth, fluid pressure equilibration in the fracture and pressure drop in a near wellbore zone. Values of fluid efficiency, minimum stress and net pressure which are determined result in a calculated pressure with respect to time matching the pressure measurements within a predetermined threshold.

The present disclosure relates to diagnosing and locating fluid leakage within a pneumatic system (5) using a minimal amount of pressure sensors (55, 75, 89). In general, each branch (51, 71, 85) of a pneumatic system (5) includes an associated pressure sensor (55, 75, 89) and in accordance with how the pneumatic components (57, 59, 61, 77, 91, 93, 95) associated with the pneumatic branch (51, 71, 85) are toggled and monitored, leaks can be detected and located within the branch (51, 71, 85) using a minimal amount of pressure sensors (55, 75, 89). More specifically, pressure and pressure decay may be measured by the sensors (55, 75, 89) within a branch (51, 71, 85) while the pneumatic components (57, 59, 61, 77, 91, 93, 95) are in a particular configuration. The configuration is thereafter changed, and pressure and pressure decay are again measured by the sensors (55, 75, 89). The results of these two measurements may enable the pneumatic system (5) to derive the presence and location of a leak.

The invention relates to a pressure-volume monitoring device for a non-metal gasket leakage experiment, and belongs to the technical field of sealing testing, the pressure-volume monitoring device comprises a gas supply mechanism, the output interface of which is connected with the gas inlet of a gas storage tank to provide an inert gas source; the signal acquisition end of the pressure measuring mechanism is embedded into the lower end of the non-metal gasket so as to acquire a gas pressure signal; the input end of the drainage measuring mechanism is connected with the exhaust port of the gas storage tank, and the drainage measuring mechanism is used for representing the volume of leaked inert gas through liquid level changes. The gas pressure change is monitored in real time through the pressure measuring mechanism, the leaked inert gas volume is represented through the liquid level change of the drainage measuring mechanism, the complex measuring process is simplified into visual liquid discharge amount, direct quantification of the leaked gas volume is achieved, and the detection accuracy is improved. Therefore, traditional pressure attenuation indirect calculation is converted into pressure-volume direct measurement, the influence of pipeline pressure drop on the measurement precision is avoided, and the measurement precision is improved.

The application provides a dynamic measurement method and system based on parallel differential pressure analysis, and relates to the technical field of gas-liquid mass transfer measurement. The method adopts a measurement unit and a control unit in parallel, a first closed container of the measurement unit containing liquid and gas, and the initial volume of the gas phase in a second closed container of the control unit being the same as the volume of the gas in the first closed container. After the pressure of the two containers is synchronously and suddenly increased to the initial pressure P0 by synchronous pressure excitation, the system is closed, and the pressure decay curves P1(t) and P2(t) in the two containers are synchronously collected. After differential processing, the influence of system leakage is eliminated, and the net pressure decay curve ΔP(t) is obtained. Based on the ideal gas state equation, the change amount of the dissolved gas mass with time is inversed, and the dissolution kinetics data are obtained. The application can dynamically and accurately measure the gas dissolution process, effectively eliminates the leakage interference, and provides key dissolution kinetics data for gas-liquid mass transfer engineering.

The invention provides an equipment maintenance life detection method, and belongs to the technical field of artillery anti-recoil device detection, and the method comprises the steps: cleaning an anti-recoil device counter-recoil machine, connecting pressure, displacement and temperature detection assemblies, and building a detection reference coordinate system; the static air pressure and the dynamic air pressure attenuation rate are synchronously obtained, and at least three sets of data are collected every 5-30 s; the counter-recoil machine is controlled to complete multiple times of simulation of recoil / counter-recoil circulation, and the air pressure leakage rate, piston rod displacement and sealing face abrasion increment are detected; calculating a maintenance life residual value; when the threshold value is less than or equal to the preset threshold value, outputting maintenance early warning; according to the equipment maintenance life detection method provided by the invention, reliable detection of the equipment maintenance life residual value is realized by simulating recoil / counter-recoil cycle to restore the actual working state, synchronously capturing key parameters such as the air pressure leakage amount, the piston rod displacement amount and the sealing surface wear increment, and combining with the life calculation model.

The invention discloses a compact sandstone gas reservoir working fluid reservoir damage evaluation system and method. The method comprises the steps that a plunger-shaped rock core of a target reservoir is dried and vacuumized, and simulated formation water is saturated; reducing the water saturation of the rock core to the original water saturation of the reservoir; the first container with the pressure being the maximum filtration loss pressure difference is communicated with the treated rock core, when the pressure in the first container is attenuated to a set value, the operation is stopped, and the pressure attenuation time is recorded; the working fluid in the rock core is saturated, then return pressure is applied to formation pressure, and gas is injected into the rock core until the gas in the rock core is saturated; and carrying out a working solution damage rock core experiment to obtain a rock core working solution damage rate and liquid saturation. According to the invention, the pressure when the actual reservoir working fluid invades is simulated by changing the return pressure, and the filtration pressure can be increased from 3.5 MPa to more than 15 MPa; reservoir damage evaluation is carried out by innovatively applying the rock core with the original water saturation of the reservoir, so that the evaluation result is more accurate.

The invention discloses a special gas system micro-leakage detection method, and belongs to the technical field of special gas system detection. The method comprises the following steps of system preprocessing, micro leakage detection, leakage point positioning and result verification. According to the method, vacuum enrichment and a tunable semiconductor laser absorption spectrum (TDLAS) technology are combined, firstly, most background gas interference is eliminated in a low-pressure environment, micro-leakage gas is enriched, and then high-selectivity and high-sensitivity detection is performed on a characteristic absorption peak by utilizing the TDLAS technology. The precision of the photoelectric detector is smaller than or equal to 1 ppm, precise quantification of the tiny leakage amount below 0.1 mL / min can be achieved in combination with precise calculation based on the Lambert-Beer law, and the detection lower limit of a traditional bubble method or a pressure attenuation method is far beyond the detection lower limit of a traditional bubble method or a traditional pressure attenuation method.

A method of automating a pressure decay integrity test of a container configured for refrigeration by a transportation refrigeration unit (TRU) is provided. The method includes connecting a controller programmed with an automated pressure decay integrity test of the container to a compressor of the TRU and a pressure transducer installed in the container and executing the automated pressure decay integrity test by the controller. The executing includes activating the compressor to pressurize the container, receiving readings of the pressure transducer and determining, from the readings, whether the automated pressure decay integrity test is passed.

The invention relates to automatically performing a pressure attenuation integrity test of a controlled atmosphere of a refrigerated container, and particularly provides a method of automatically performing a pressure attenuation integrity test of a container configured to be refrigerated by a transport refrigeration unit (TRU). The method includes connecting a controller programmed with a pressure decay integrity test of the container to a compressor of the TRU and a pressure transducer mounted in the container, and performing the pressure decay integrity test by the controller. The performing includes: starting the compressor to pressurize the container; receiving the reading of the pressure transducer; and determining, from the readings, whether the pressure attenuation integrity test is passed.

The present application relates to the technical field of intelligent control and predictive maintenance of heating water heaters, in particular to a wind pressure switch control system for heating water heaters and a method thereof; the method collects time sequence pressure signals in the working cycle of the fan, extracts the starting pressure curve slope, steady state pressure fluctuation spectrum entropy and shutdown pressure decay time constant to generate a dynamic feature vector; the system compares the vector with a preset reference health vector, and real-time calculates the system health state confidence and state deviation drift rate; when the health confidence is lower than the safety threshold or the deviation drift rate is too fast, the system performs forced safety locking; if the health degree slightly decreases, the fan pre-blowing time is actively extended as compensation; the present application realizes the transition from fault response to predictive maintenance, can identify early performance degradation signs such as fan wear and air duct dust accumulation in advance, changes after-maintenance to pre-intervention, and effectively reduces the failure rate and maintenance cost.

The present invention provides an improved GIP porosity measurement method based on pressure decay, which relates to the technical field of porosity measurement; this method mainly includes building a GIP porosity experimental system with a standard tank and a matrix cup, storing a gas with a predetermined pressure in the standard tank, and placing a rock sample in the matrix cup. Assuming the gas diffusion sequence, constructing a diffusion flux expression according to the pressure distribution characteristics of the rock sample, substituting it into the pressure perturbation propagation model to obtain the surface pressure expression, and then modifying and constructing the pressure decay model in the matrix cup. During the experiment, the volumes and pressure decline data of the standard tank and the matrix cup are obtained, and the equilibrium pressure is obtained by fitting with the decay model, and the rock sample skeleton volume and porosity are calculated by substituting into the formula. The present invention can obtain the equilibrium pressure through the pressure decay model in the matrix cup without a complete pressure drop curve, greatly shortening the acquisition time and improving the experimental efficiency, providing a faster and more accurate measurement method for shale porosity measurement, and having important significance for related research and engineering applications such as shale gas reservoir evaluation.

The present invention discloses an intelligent soft measurement method for the dynamic total pressure of a high-temperature gas flow based on multi-dynamics of a micro-cavity, comprising the following steps: step 1, mathematical modeling of the dynamic process of total pressure decay in a micro-cavity in the flow field; step 2, mathematical modeling of the coupling process of temperature on dynamic total pressure in the flow field; step 3, design of a principle prototype of a short-tube piezoresistive intelligent pressure sensor; and step 4, design of an intelligent soft measurement method for the dynamic total pressure of a high-temperature gas. In the intelligent soft measurement method for the dynamic total pressure of a high-temperature gas flow based on a short-tube proposed in the present invention, the performance model is combined with an intelligent method to solve the scientific problems of the total pressure decay mechanism of gas in a micro-cavity and the coupling mechanism of temperature and pressure in a micro-cavity, a dynamic total pressure recovery model and a dynamic total pressure temperature correction model in a micro-cavity are established, a principle prototype of an intelligent total pressure sensor is designed, and an intelligent soft measurement method for dynamic total pressure is proposed based on the dynamic total pressure recovery model and the dynamic total pressure temperature correction model.

The invention belongs to the technical field of silicone oil injection amount verification, and relates to a silicone oil injection amount verification device of a leakage-free viscous damper and a using method, and the silicone oil injection amount verification device comprises a pretreatment and purification treatment detection module used for monitoring the PH value of circulating fluid in real time, achieving the impurity removal rate through a three-stage filter element and constructing a water quality safety evaluation model, and an injection monitoring module, the volume conversion module is used for collecting water injection rate data in real time through an electromagnetic flowmeter and constructing a volume conversion model in combination with a density ratio formula, and the leakage detection module is used for integrating a visual recognition system and a pressure attenuation algorithm and constructing a dual-channel leakage judgment model. The overflow track is captured in real time through the visual recognition mode of the leakage detection module, the water pressure in the damper cavity is detected in real time in cooperation with pressure attenuation, double-channel complementary detection is achieved, the confidence coefficient of judging whether the damper leaks liquid or not is improved, and meanwhile the leakage detection accuracy is improved through the hot air flow speed and the temperature gradient. Therefore, comprehensive detection of gas-liquid leakage of the damper is realized.

This application provides an interactive method and system for detecting large leaks in energy storage air conditioners, relating to the field of energy storage air conditioner technology. This method significantly improves the convenience and consistency of large leak detection by integrating a full-process interactive interface that includes workpiece model selection, intelligent parameter configuration, one-click start, real-time multi-dimensional monitoring, and result visualization and backtracking. Users can quickly select the model and automatically load suitable flexible pressurization rules and gradient pressure relief programs, avoiding manual missetting. During the detection process, the current stage, pressure value, pressure-time curve, remaining pressure holding time, and acoustic emission status are dynamically displayed, allowing real-time monitoring of pressure resistance and structural safety, preventing damage to the workpiece structure during large leak detection. After completion, the judgment result is automatically displayed, linked to historical records, pressure decay rate, and alarm logs. It supports process curve playback and one-click generation of standardized test reports, greatly improving efficiency, traceability, and quality control.

The present disclosure relates to diagnosing and locating fluid leaks within a pneumatic system (5) using a minimum number of pressure sensors (55, 75, 89). Typically, each branch (51, 71, 85) of the pneumatic system (5) includes an associated pressure sensor (55, 75, 89), and depending on how the pneumatic components (57, 59, 61, 77, 91, 93, 95) associated with the pneumatic branch (51, 71, 85) are switched and monitored, a minimum number of pressure sensors (55, 75, 89) can be used to detect and locate leaks within the branch (51, 71, 85). More specifically, when the pneumatic components (57, 59, 61, 77, 91, 93, 95) are in a particular configuration, the pressure and pressure decay within the branch (51, 71, 85) can be measured by the sensors (55, 75, 89). Thereafter, the configuration is changed, and the pressure and pressure decay are again measured by the sensors (55, 75, 89). The results of these two measurements can enable the pneumatic system (5) to ascertain the existence and location of a leak.

The invention discloses a high-pressure hydrogen storage equipment leakage diffusion test method and device, a medium and equipment, and relates to the technical field of high-pressure hydrogen storage equipment safety. The method comprises the steps that in the leakage diffusion test process of the high-pressure hydrogen storage equipment, the leakage volume of hydrogen and pressure data of the hydrogen are collected, and the average pressure change rate of the hydrogen is calculated based on the pressure data; based on the average pressure change rate of the hydrogen, the leakage volume is corrected through a leakage volume correction formula, and the corrected leakage volume is obtained; the leakage volume correction formula is constructed according to the influence of quantitative hydrogen pressure attenuation on the leakage volume; and the corrected leakage volume is substituted into a leakage rate calculation formula for calculation, and the hydrogen leakage rate is obtained. The method improves the test precision of the leakage rate of the high-pressure hydrogen storage equipment.

Methods of diagnosing and detecting and locating leaks in a pneumatic system are provided. Pressurizing a first passage, the passage extending from the manifold through the valve to the first fitting; measuring a first pressure attenuation within the first channel based at least in part on a change in pressure within the first channel over a first period of time; pressurizing a second passage, the passage extending from the manifold through the valve to the second fitting; measuring a second pressure attenuation within the second channel based at least in part on a change in pressure within the second channel over a second time period; comparing the first and second pressure attenuations with a limit threshold; in response to determining that the first and second pressure attenuations are greater than a limit threshold, determining that there is a leak between the manifold and the valve; in response to determining that the first pressure attenuation is greater than the limit threshold and the second pressure attenuation is less than the limit threshold, determining that there is a leak between the valve and the first fitting; in response to determining that the first pressure attenuation is less than the limit threshold and the second pressure attenuation is greater than the limit threshold, it is determined that there is a leak between the valve and the second fitting.

The invention provides a mold detection device for an aluminum alloy tension bar, and relates to the technical field of mold detection, and the mold detection device comprises a mold inner cavity online monitoring module, a locking mechanism health state diagnosis module, a parting surface sealing performance detection module and a mold detection report output module. The shape precision and surface precision data can be comprehensively obtained through the mold inner cavity online monitoring module so as to avoid the defects of burrs, size out-of-tolerance and the like of a tension bar, and faults such as thread abrasion, lubrication failure or clamping seat deformation and the like can be accurately evaluated through the locking mechanism health state diagnosis module so as to avoid mold leakage, flash and production interruption; a trace amount of low-pressure gas is injected after mold closing and locking and before pouring through the parting surface sealing performance detection module, the pressure attenuation rate and an ultrasonic signal are monitored, the sealing state can be quantitatively evaluated, the flash risk can be predicted, and the follow-up cleaning workload and cost are reduced.