1794 results about "Inlet pressure" patented technology

The invention relates to the technical field of water and fertilizer drip irrigation, in particular to a biogas slurry, water and fertilizer integrated drip irrigation machine. Comprising a filter cartridge which is coaxially arranged in the outer cylinder, a coarse filter screen, a fine filter screen, a first scraper blade and a second scraper blade are arranged in the filter cartridge, water permeable holes are annularly and uniformly formed in the outer side wall of a lower cavity, and a water outlet is formed in the outer side wall of the lower cavity. And a blow-off pipe communicated with the filter cartridge is arranged at the bottom of the outer barrel. By means of multi-layer fine filtering combination, biogas slurry is purified at an irrigation inlet, impurities are reduced, a drip irrigation head is prevented from being blocked, and the irrigation efficiency is improved; the rotary driving mechanism regularly drives the scraping plate to accurately scrape impurities, and automatic cleaning and discharging are achieved by means of the locking opening and closing device and the movable sealing plate; the flow guide cover optimizes biogas slurry dispersion, deals with unstable supply and reduces pipe inlet pressure.

The invention discloses a pipeline medium leakage detection method, device and equipment, a storage medium and a product, and is applied to the technical field of pipeline engineering. The method comprises the following steps: constructing a training data set based on pressure and flow historical data of an inlet and an outlet of a pipeline, and constructing a mechanism model according to a pipeline medium dynamic relationship; and training the mechanism model by using the driving model training data set to obtain a driving model, and finely adjusting the driving model by using the leakage detection fine adjustment data set to obtain the pipeline medium leakage detection model under the variable working conditions. A media leakage threshold is determined based on a difference between the predicted value of the drive model and the corresponding monitored value. And inputting the flow data and the outlet pressure data of the to-be-detected pipeline into the model, and determining whether the to-be-detected pipeline medium leaks or not based on the difference value between the model output and the inlet pressure monitoring data and the medium leakage threshold value. According to the invention, the problem of poor detection precision of pipeline medium leakage in related technologies can be solved, and high-precision detection of pipeline medium tiny leakage under variable working conditions is realized.

The invention discloses a steam compressor system and a control method. The system comprises a steam compressor, a controller, a heat exchange device, and a steam inlet pressure detection device, a steam exhaust pressure detection device and a steam flow detection device which are respectively connected with the controller, the heat exchange device internally comprises a gas phase area and a liquid phase area, and the gas phase area is communicated with a steam inlet of the steam compressor through a steam inlet pipeline; the steam inlet pressure detection device is arranged on the steam inlet pipeline; a heat exchange coil and a heating device are arranged in the liquid phase area; an inlet of the heat exchange coil is communicated with a steam outlet of the steam compressor through a steam exhaust pipeline; the steam exhaust pressure detection device and the steam flow detection device are arranged on the steam exhaust pipeline; an outlet of the heat exchange coil extends to the outside of the heat exchange device; and the controller is respectively connected with the steam compressor and the heating device. According to the steam compressor system provided by the embodiment of the invention, the steam heat can be recycled, so that the energy consumption of the steam compressor test is reduced, and the test cost is reduced.

The invention discloses a supercharging optimization control method based on ignition efficiency, which comprises the following steps of: periodically detecting a supercharging closed-loop enabling condition for an engine, and when the state of the engine is changed from a state meeting the supercharging closed-loop enabling condition to a state not meeting the supercharging closed-loop enabling condition, starting the ignition efficiency; according to the ratio of the actual outlet pressure to the actual inlet pressure of the throttle valve and the current real-time rotating speed of the engine, the initial duration value when the target opening degree of the supercharging actuator is kept unchanged is determined; determining remaining time according to the duration initial value, and updating and optimizing the remaining time according to the ignition angle efficiency variable quantity to obtain optimized remaining time; and the optimized remaining time serves as the maintaining time of the opening degree of the pressurization actuator through pressurization closed-loop enabling, and the pressurization process is controlled according to the maintaining time. According to the method, the problems of control smoothness and stability possibly caused when the pressurization closed loop is quitted are optimized, and the stability of the air inlet pressure and the pressure of an outlet of the supercharger in the quitting process of the pressurization closed loop is improved.

The invention relates to the field of hydroelectric generation automation control, discloses an intelligent flow-pressure double closed-loop control method and system for a water inlet ball valve of a water turbine, and aims to solve the technical problems that flow stability and pressure fluctuation suppression are difficult to consider, dynamic response is delayed and working condition adaptability is poor in existing single-loop control. The method comprises the steps that inlet pressure and flow data are collected in real time through a pressure sensor and an ultrasonic flowmeter, a cascade structure of outer ring flow control and inner ring pressure control is constructed in combination with working condition parameters such as the rotating speed of a unit and the opening degree of a guide vane, and a working condition self-adaptive weight distribution module is introduced to dynamically adjust the double-ring gain coefficient; meanwhile, a feed-forward compensation mechanism and an optimal efficiency curve database are fused, and dynamic matching of set values and advanced response of load instructions are achieved. The system comprises a data acquisition unit, a double-closed-loop control unit, a weight distribution unit, an electro-hydraulic servo execution mechanism and a safety interlocking module, and supports microsecond-level gain updating and high-precision valve position control. According to the technical scheme, the adjusting precision and the response speed of the water turbine under the complex working condition are remarkably improved, the actual measurement efficiency is improved by 2.5%-4.8%, the adjusting time is shortened to be within 3 seconds, the positioning precision reaches + / -0.5 degree, and safe and stable operation of the system is guaranteed.

According to the hydraulic power plant electromechanical equipment state monitoring informatization management system provided by the embodiment of the invention, data monitoring and analysis are performed on pressure of a water inlet and a water outlet of a water turbine by adopting an artificial intelligence technology based on deep learning, and time sequence dynamic change modes of the pressure of the water inlet and the pressure of the water outlet in a local time domain are respectively extracted; and principal component feature joint coding is carried out on the water inlet pressure and the water outlet pressure in a local time domain to obtain pressure cooperative change information of the water inlet and the water outlet of the water turbine, and then global time domain aggregation is carried out on the pressure cooperative change information to realize intelligent identification of the leakage state of the water turbine. Therefore, the operation efficiency and the safety performance of the hydropower station can be effectively improved, and meanwhile the maintenance cost and the fault processing time are reduced.

The invention relates to the technical field of on-line monitoring, in particular to an on-line monitoring system for the flowing state of a sludge conveying pipeline, which comprises a real-time parameter acquisition module, a real-time monitoring module, a real-time monitoring module and a real-time monitoring module, based on real-time monitoring of running parameters, rotating speed, outlet pressure and inlet pressure of a sludge pump and flow and pressure data of the tail end or the middle point of the sludge conveying pipeline; and obtaining a current system operation parameter snapshot. According to the method, multi-dimensional operation parameters including the rotating speed, the outlet pressure and the inlet pressure of the sludge pump are obtained in real time, and the flow and pressure data of the tail end or the middle point of the pipeline are combined to construct a system operation snapshot, so that the state change in the sludge conveying process can be captured; theoretical hydraulic conveying parameters are calculated by combining inlet pressure and rotating speed data with sludge rheological characteristics, geometric dimension parameters of a conveying pipeline are introduced to derive a flow prediction value of a target monitoring point, and therefore a prediction benchmark with a wider coverage range is established in the spatial dimension.

The invention relates to a method and device for obtaining the actual supercharging pressure of an engine. The method comprises the steps that the air inlet pressure of an outlet of a throttle valve and the air inlet pressure of an inlet of the throttle valve are obtained; and judging whether the throttle valve is in a normal control mode, an anti-overshoot control mode or a full-open control mode, and for different modes, selecting corresponding transition coefficients to calculate the actual boost pressure of the engine by combining the intake pressure of the outlet of the throttle valve and the intake pressure of the inlet of the throttle valve. According to the method, on the basis of different working modes of the throttle valve, the boost pressure control deviation, the intake pressure control deviation and the intake pressure response condition are considered at the same time, the calculation method of the actual boost pressure is optimized, meanwhile, learning parameters of the actual boost pressure are continuously updated in different life cycles, and the control precision of the intake pressure is improved.

The invention relates to the technical field of medical instruments, and provides a pneumoperitoneum machine pressure measurement abnormity control method which comprises the following steps: acquiring air inlet pressure, pressure measurement pressure and smoke exhaust pressure; calculating a difference value between the air inlet pressure and the pressure measuring pressure and a difference value between the pressure measuring pressure and the smoke exhaust pressure; when the difference value between the air inlet pressure and the pressure measuring pressure is larger than a first preset difference value and smaller than a second preset difference value, and the difference value between the pressure measuring pressure and the smoke discharging pressure is larger than a third preset difference value and smaller than a fourth preset difference value, the pressure measuring pressure is selected as display pressure; otherwise, starting a first pressure measurement abnormity detection program. By monitoring the difference value between the air inlet pressure and the measured pressure and the change of the difference value between the measured pressure and the smoke exhaust pressure, pressure monitoring abnormity caused by equipment faults in the operation process can be recognized, the equipment stability is improved, and the operation risk is reduced.

The invention discloses an integrated device and method for comprehensively evaluating and measuring the filtering performance of a filter material in a filter tank. The integrated device comprises a box body structure, wherein a water inlet and outlet system, a filtering system, a backwashing system, a pressure difference measuring pipe system, a PLC control system and the like are arranged in the box body; the device adopts a water pump to feed water, the water inlet pressure adjusting range is wide, and the pressure drop difference of the filter layer can be equal to the thickness in a proper particle size range; when the filtering speed is too high, the permeability coefficient can be analyzed by adopting two or more than two pressure drop differences and an instantaneous filtering speed fitting change curve. The filtering system can set constant filtering speed and turbidity (suspended solids), the turbidity (suspended solids) and head loss are measured after the filtering system runs for a certain time, and the filtering performance of the filtering system is analyzed according to an index system. The water inlet and outlet ports of the filter column are arranged at equal intervals and in equal size, the measuring pipe can be detached and heightened, filter materials do not need to be replaced, gas and water backwashing can be achieved, integrated movement can be achieved, and switching of analysis and measuring modes of filter layers with different heights in the filter column is facilitated.

The invention provides an analysis method and device for flow, efficiency and water consumption rate of a hydraulic power plant generator set. A distributed flow measurement unit based on a domestic PLC controller and a domestic operating system is constructed, and each unit is independently configured with the flow measurement unit to realize decentralization of data acquisition and processing; active power, guide vane opening, water head difference, instantaneous flow and volute inlet pressure data are collected in real time through a distributed flow measurement unit, and a unit efficiency and water consumption rate calculation model is dynamically fitted based on the data; sending an output result of the calculation model to a monitoring system through an anti-interference communication network, wherein the communication network adopts layered wiring and a double-shielded twisted pair to reduce the signal bit error rate; and the IMC integrated management and control platform is used for remote monitoring and diagnosis of the flow measurement unit, and seamless connection with a smart power plant data medium station is realized. The system reliability and the maintenance flexibility are improved, and the autonomous controllable requirements of domestic substitution and intelligent power plants are comprehensively met.

The invention provides an abrasive flow polishing device and method for gear tooth surface homogenization. According to the method, tooth-shaped drainage pieces with the same shape as the gear are installed at the two ends of the upper portion and the lower portion of the gear, drainage section design is introduced, an abrasive flow medium path runner model is constructed, main parameters influencing an experiment are sampled and grouped through a Latin hypercube sampling method, abrasive flow polishing simulation is conducted in a grouped mode, and a Gaussian regression process is utilized to obtain an abrasive flow polishing simulation result. Selecting the minimum root-mean-square error of each group of PiVi data, determining the group of experimental parameters, obtaining a group of abrasive flow machining process parameters of optimal inlet pressure, back pressure and drainage section length, and finally guiding the experiment; according to the method, the influence of the inlet effect is relieved, the abrasive flow medium path runner model is constructed, a set of optimal abrasive flow machining process parameter combination is obtained, and the method is suitable for spur gears and bevel gears and high in universality.

The embodiment of the invention discloses an anti-surge control method and device for a compressor, the compressor, a storage medium and a program product. Wherein an inlet pressure measuring module and an inlet regulating valve are arranged on the gas inlet side of the compressor, and an outlet pressure measuring module and an outlet regulating valve are arranged on the gas outlet side of the compressor; the method comprises the steps that the current inlet pressure, measured by an inlet pressure measuring module, of a compressor and the current outlet pressure, measured by an outlet pressure measuring module, of the compressor are obtained, and the current pressure difference of an inlet and an outlet of the compressor is calculated; comparing the current pressure difference with a set pressure difference threshold value to obtain a regulation and control parameter; determining a current control interval from a predetermined split-range control model based on the regulation and control parameters; and on the basis of the current control interval, opening control is conducted on at least one of the inlet adjusting valve and the outlet adjusting valve. According to the technical scheme, the surge risk of the compressor can be effectively reduced.

A method for controlling a flow regulating valve (6) of a filling machine (1), controlling the flow of pourable food product, envisages: receiving an inlet pressure measurement (PIN) from a pressure sensor (14); receiving an inlet flow measurement (FIN) from a flow meter (16); determining a control signal (Sc) for controlling an operating position of the flow regulating valve (6) by combined contributions (C1, C2) of a flow feedback control module (22), receiving at its input a flow set point (FSP) and the inlet flow measurement (FIN) and generating a first control contribution (C1) indicative of a difference between the inlet flow measurement and the flow set point; and a flow feed-forward control module (20), receiving at its input the inlet pressure measurement (PIN) and the flow set point (FSP) and generating a second control contribution (C2) as a function of the flow set point and inlet pressure measurement, using pre-stored fluid-dynamic maps, which may be a result of a characterization of the flow regulating valve in a test condition. The flow feed-forward control module uses the fluid dynamics maps in a dynamically adaptive manner, depending on different operating conditions of the filling machine and / or the related pourable food product, thereby adapting to the same different operating conditions and / or the pourable food product.

The invention belongs to the field of sewage treatment, and discloses a low-solid-content sewage cyclone desanding system and a control method thereof.The low-solid-content sewage cyclone desanding system comprises a pressure transmitter arranged on a water inlet pipe; the plurality of hydrocyclones are connected with the water inlet pipe; the plurality of first valves are arranged on an inlet pipeline of the cyclone and are associated with the pressure transmitter; a sand collecting chamber is arranged at a first sand discharging opening of the cyclone; the sand collecting chamber outlet end is provided with a second valve; the sand-water separator is connected with the outlet end of the second valve; the controller is connected with the pressure transmitter, the first valve, the cyclone, the second valve and the sand-water separator; the hydrocyclones, the first valves, the sand collecting chambers and the second valves are equal in number and are correspondingly arranged on the parallel branches, and the number of the parallel branches is three or more. The system can automatically regulate and control the operation of the cyclone according to the total water inlet pressure fluctuation, solves the problems of unstable operation flow state, poor sand removal effect and the like caused by water inlet flow fluctuation, is suitable for sand removal treatment of sewage with large water inlet fluctuation and low solid content, and is efficient and stable in operation and good in sand removal effect.

The invention provides a well-station-oil depot coupling simulation-based crude oil coagulation risk optimization method, which comprises the following steps of: firstly, designing a well-station-oil depot pipe network system topological structure, analyzing a pipe network structure, and numbering wells, stations, oil depots and pipelines to obtain the numbers of an upstream pipeline and a downstream pipeline of each pipeline; then, a well-station-oil depot pipe network system is disassembled into a node + pipeline form, each pipeline is dispersed into a plurality of calculation units, and the pipe section length, diameter and dip angle of each calculation unit are obtained; according to the fluid temperature of each wellhead, the fluid entering pressure of each station and a PVT physical property table, assuming the temperature and pressure of all nodes to obtain the average temperature and pressure of each pipe section; and calculating crude oil physical property parameters, crude oil flow parameters, pressure drop and temperature drop parameters of each pipe section by adopting an iterative method to obtain pressure and temperature of all nodes, and finally judging the pipe condensation risk according to the physical property parameters and the pipeline pressure and temperature. The pipe condensation risk can be automatically judged, and the production efficiency and safety are improved.

The invention discloses a water pump control method, device and equipment for production, a medium and a product, and relates to the technical field of pump station control. The method is executed by a central control host of a water pump control system for production, and comprises the following steps of: sorting according to water pump operation parameters, a water pump water inlet pressure value and a water pump water outlet pressure value which are received in real time in a current latest time period to obtain multi-dimensional time sequence data of a current online water pump; secondly, the time sequence data are imported into a water pump fault probability prediction model which completes pre-training based on a time sequence model, and the probability that the current online water pump breaks down in the current next time period is output and obtained; and generating a water pump switching control instruction used for indicating to stop the current online water pump and start the current offline water pump, and finally transmitting the control instruction to the pump station control cabinet for execution, thereby reducing the fault probability of the whole pump station in a multi-water-pump parallel use scene of the pump station.

The invention relates to the technical field of valve detection, in particular to a valve inlet pressure testing mechanism which comprises a testing valve, and a supporting structure is arranged outside the testing valve. The supporting structure comprises a supporting base, two mounting seats and two butt-joint sealing pipes; the outer surfaces of the two mounting seats are both provided with testing mechanisms communicated with the two butt joint sealing pipes, each testing mechanism comprises a shell, a through pipe, a piston, a limiting strip and an ejector rod, and the through pipe is fixedly communicated between the shell and the air pipe; and a speed regulating mechanism for reciprocating the ejector rod is arranged outside one of the mounting seats and comprises a rotary drum, a mounting outer shell, a mounting inner shell, an elastic telescopic pipe, a roller, a driving motor, a connecting shaft, a transmission gear, a driven gear, a butt joint rod, a regulating gear, a sliding seat, a motor and a rack. The moving speed and pressure of the piston can be adjusted, the testing efficiency and the testing consistency are improved, and then the testing accuracy is enhanced.

The invention discloses an air inlet pressure and temperature sensor resistor and shell assembling device which comprises a divider rotary table, a tool, an operation opening, a forming pin, a shell feeding mechanical arm, a resistor feeding mechanical arm and a shaping die. An operation opening used for opening a resistor pin is formed in the tool, the divider rotary table is provided with a forming pin in butt joint with the operation opening, the forming pin is used for directionally bending the resistor pin, and the tool is in butt joint with the shell feeding mechanical arm and the resistor feeding mechanical arm. By means of the mode, according to the air inlet pressure and temperature sensor resistor and shell assembling equipment, pre-shaping treatment is conducted on resistor pins through the shaping die, fine fixed-point bending operation on the pins is accurately achieved through the forming pins, and resistor welding and UV curing stations are integrated in the whole machine; the automatic production and processing of the resistance part of the air inlet pressure sensor are efficiently realized, and the productivity and the yield are obviously improved.

A mass flow controller and a flow control method therefor. The method comprises: receiving the value of a set flow point (S110); acquiring a measured value of the gas inlet pressure of a mass flow controller under an actual operation condition (S120); and on the basis of a first preset relational expression between the value of the set flow point that is calibrated when the gas inlet pressure is a standard pressure value and a driving parameter of a regulation valve of the mass flow controller, obtaining a standard value of the driving parameter that corresponds to the value of the set flow point, and on the basis of a comparative relationship between the measured value and the standard pressure value, selectively performing pressure compensation on the standard value of the driving parameter to obtain a selective compensation output value of the driving parameter and accordingly control the regulation valve, so as to adjust the opening degree of the regulation valve to an opening degree corresponding to the selective compensation output value of the driving parameter (S130). By using the method, a mass flow controller exhibits high consistency in response time under different set flow points and different gas inlet pressures, and has a fast response speed, thereby improving the control accuracy of the mass flow controller.

The invention discloses a test system and a test method for high-temperature solid oxide water electrolysis hydrogen production. The test system comprises a gas supply device, a heating unit, a back pressure stabilizing unit and a control unit, the back pressure stabilizing unit is connected with a cathode outlet of the SOEC stack and comprises a back pressure sensor, a first pressure regulating valve and a variable-frequency speed regulating induced draft fan; and the control unit takes back pressure data acquired by the back pressure sensor and air inlet pressure data acquired by the air inlet sensor arranged at the cathode inlet of the SOEC stack as parameters, and generates an adjusting instruction of the first pressure adjusting valve and / or the variable frequency speed adjusting induced draft fan according to a preset rule. According to the invention, performance testing can be carried out on a large-scale single electric pile and a module group composed of a plurality of small-scale or medium-scale electric piles in a large-power range; in addition, different combination modes of series connection and parallel connection between multiple electric piles and the change rule of the electrolysis performance can be tested, and then a more compact and efficient multi-electric-pile matching module can be obtained.

The invention relates to the technical field of hydraulic mechanical transmission, in particular to a hydraulic torque converter assembly, a vehicle and a control method. The hydraulic torque converter assembly comprises a hydraulic torque converter, a pressure adjusting assembly and a rotating direction adjusting assembly, wherein the hydraulic torque converter is provided with an output shaft; the pressure adjusting assembly is connected to an oil inlet of the hydraulic torque converter and used for adjusting the pressure of the oil inlet of the hydraulic torque converter. The rotating direction adjusting assembly is connected with the output shaft and used for changing the rotating direction of the output shaft. When a vehicle goes down a long slope, the rotation direction of the output shaft is changed through the rotation direction adjusting assembly, the requirement for long-time retarding braking of the vehicle is met through the reverse rotation characteristic of the torque converter, compared with traditional reverse transmission braking, higher braking torque can be provided, and due to the fact that the pressure of an oil inlet of the hydraulic torque converter is adjustable, automatic adjustment can be conducted according to different braking torque requirements; and different slope requirements when the vehicle goes down a long slope working condition are met.

The invention discloses a safety valve service life evaluation method based on pressure history statistics and dynamic damage accumulation. According to the method, only safety valve inlet pressure time sequence data is needed, a load cycle is extracted through an improved rain flow counting method, and the nonlinear damage increment is calculated according to an S-N curve model dynamically degraded along with the accumulated damage degree. According to the method, a self-adaptive failure probability threshold is established based on historical failure data, and probabilistic prediction of the residual life is realized. The model is clear in physical significance, only needs a single data source, significantly reduces the implementation complexity and cost, greatly improves the precision of life prediction by considering the degradation of material performance, and is especially suitable for predicting the accelerated failure risk of the safety valve in the later period of long-term service.

The invention belongs to the field of plant extracting solution concentration, and discloses a low-pressure high-power concentration device for a plant extracting solution and a concentration method using the low-pressure high-power concentration device. The device is based on a series reverse osmosis membrane stack and a feeding pump, a fresh water collecting tank, a booster pump, three types of pressure sensors, two types of osmometers, a water inlet pressure control system and a one-way valve are additionally arranged, the three types of pressure sensors are used for detecting the pressure of a feeding header pipe, the pressure of concentrated water and the pressure of a fresh water header pipe respectively, and the two types of osmometers are used for detecting the osmotic pressure of the feeding header pipe and the osmotic pressure of the concentrated water respectively. The water inlet pressure control system adjusts the design pressure of the device and the osmotic pressure of the plant extracting solution by adjusting the frequencies of the booster pump and the feeding pump, so that accurate monitoring of parameters is realized, efficient concentration of the plant extracting solution under low pressure is guaranteed, scaling on the surface of a reverse osmosis membrane is delayed, the service life of a membrane stack is prolonged, and continuous production of membrane concentration and filtration is realized.

The invention discloses an anti-surge control method for a compressor unit, and particularly relates to the field of operation control of the compressor unit, a plurality of sensor terminals for pressure, flow, temperature and the like are deployed in the installation and debugging stage of the compressor unit, working parameters such as air inlet pressure, flow, exhaust pressure and the like are collected in real time, and data are preprocessed after collection; smoothing data by adopting a moving average filtering method, cleaning abnormal values according to a 3 sigma principle, processing missing values according to a missing proportion and normalizing the missing values, constructing an operation condition model based on preprocessed data, and calculating anti-surge threshold values in low, medium and high load areas by combining parameters such as air inlet flow and exhaust pressure; and constructing an exhaust pressure and intake flow prediction model by using historical data, and predicting a future state. The surge state is judged by comparing the predicted value with the threshold value, then the opening degree of the air inlet and exhaust adjusting valve is adjusted, stable operation of the compressor unit is guaranteed, the surge phenomenon is effectively prevented, and the operation safety and reliability of the compressor unit are improved.

The invention provides a cooling device and a control method thereof, a storage medium and a program product, and relates to the technical field of cooling. The cooling device comprises a filtering system; the filtering system comprises a filter, an inlet pressure sensor, an outlet pressure sensor, a pump front switching valve, a one-way valve, a flushing pump, a sewage draining switching valve and an outlet switching valve; the filter comprises a barrel and a filter element located in the barrel, and the barrel comprises an inlet, an outlet and a drain outlet located between the inlet and the outlet; the one-way valve is arranged at the inlet, is sequentially connected with the filters and then is connected in parallel with the pre-pump switch valve and the flushing pump which are sequentially connected; the before-pumping switch valve is close to the one-way valve; the inlet pressure sensor is arranged at one end of the filtering system close to the refrigerating system; the outlet switch valve and the outlet pressure sensor are arranged at the end, close to the cooling system, of the filtering system. Automatic cleaning is achieved, manual intervention is not needed, time and labor are saved, and the service life of the filter element can be greatly prolonged.

The invention relates to the technical field of pumps, and discloses a reliable double-shell self-balancing multi-stage centrifugal pump, a low-pressure section is provided with a medium inlet and an inducer chamber, the two ends of the inducer chamber communicate with the medium inlet and a fluid cavity correspondingly, and an inducer connected to a pump shaft is arranged in the inducer chamber; the pump shaft sleeve is provided with a throttling ring, the throttling ring is located at the end, away from the low-pressure section, of the high-pressure section, drainage threads are arranged on the periphery of the throttling ring, a throttling channel is defined between the drainage threads and the high-pressure section, the mechanical seal base is provided with a pressure relief channel, one end of the throttling channel is communicated with the fluid cavity, and the other end of the throttling channel is communicated with the pressure relief channel. And the pressure relief channel is communicated with the inducer chamber through a pressure relief pipe. According to the reliable double-shell self-balancing multi-stage centrifugal pump, the throttling ring is driven by the pump shaft to rotate, the inlet pressure is effectively increased, cavitation is prevented, the throttling channel has the pressure relief effect on the high-pressure section, the impact load of a high-pressure medium on the pump shaft, the bearing and the bearing box is relieved, the operation stability of the pump is improved, and the service life of the pump is prolonged.

The utility model belongs to the technical field of sewage treatment, and provides a low-solid-content sewage cyclone desanding system which comprises a pressure transmitter arranged on a water inlet pipe; the plurality of hydrocyclones are arranged behind the pressure transmitter in parallel; the plurality of first valves are respectively arranged on inlet pipelines of the hydrocyclones, and each first valve is associated with the pressure transmitter; the plurality of sand collecting chambers are respectively arranged at the first sand discharging openings in the lower parts of the hydrocyclones; the plurality of second valves are respectively arranged on the outlet pipeline of each sand collecting chamber; and the sand-water separator is connected with the outlet end of each second valve. The cyclone desanding system can automatically control the operation according to the water inlet pressure change to realize dynamic balance, is suitable for desanding treatment of sewage with large water inlet amount fluctuation and low solid content, and is efficient and stable in system operation and good in desanding effect.

The invention provides a volumetric supercritical carbon dioxide Brayton cycle variable load system, belongs to the technical field of supercritical carbon dioxide Brayton cycle power generation, and can at least partially solve the problems that an existing steam Rankine cycle unit does not utilize the supercritical carbon dioxide Brayton cycle to integrally operate on a supercritical point and has no project. The Brayton cycle system comprises a compressor, a main loop and an adjusting branch, the adjusting branch comprises a pressure adjusting assembly, the amount of circulating carbon dioxide working media in the system is adjusted, the inlet pressure of the compressor is adjusted, and the working point of the compressor is changed; the temperature and pressure of the carbon dioxide working medium at the turbine inlet are changed by adjusting the heat exchange amount of the heat source heat exchanger, and rapid load changing is achieved.

The invention relates to the technical field of electromagnetic valves, in particular to an air pump electromagnetic valve capable of adaptively adjusting displacement, which comprises a valve seat, an electromagnet, an adjusting rod, a valve core and a movable piece, the interior of the valve seat is divided into an outer cavity and an inner cavity, a first communication port is arranged between the outer cavity and the inner cavity, and the movable piece in transmission connection with the valve core is arranged in the inner cavity; the valve element is connected with an adjusting rod in the electromagnet valve element through an elastic assembly, and by adjusting the installation height of the adjusting rod in the armature, it can be ensured that when the valve element is located at the preset position, the second communication opening and the first communication opening in the movable part are mutually staggered, and a throttling opening with the normal opening degree is formed; the valve element drives the movable part to move up and down, and the opening degree of the throttling opening is dynamically adjusted, so that the air outlet pressure is adaptively controlled according to the air inlet pressure, the air outlet pressure is stabilized within the set range, the problem that a traditional electromagnetic valve is difficult to respond to dynamic pressure changes is effectively solved, and constant adjustment of the outlet pressure is achieved.