1336 results about "Constant pressure" patented technology

The invention discloses a method for preparing a single-layer tungsten diselenide nanoband based on a space confinement strategy. By changing the flow and the growth time of hydrogen, effective control on the width and the thickness of a nanoband can be realized. The method comprises the following steps: uniformly spraying tungsten trioxide powder to one substrate, then covering the substrate by the other substrate, and forming micro reaction space which is of a 'sandwich'-like structure. Growth of a tungsten diselenide nanoband is carried out by utilizing a constant-pressure chemical vapor deposition method; physicochemical characteristics of a one-dimensional transition metal chalcogenide strongly depend on suspension key types on the edge of the one-dimensional transition metal chalcogenide, metallic properties are displayed by an ultranarrow band, and conversion from the metallic properties to semiconductor properties can be displayed from the edge to the center of a wider band; the tungsten diselenide nanoband is widely applied to micro-nano photoelectric devices due to the special property; industrial production of the tungsten diselenide nanoband can be realized through an experimental method of the invention.

The invention provides a robust control automatic setting method for a constant-pressure water supply system, and the method comprises the steps: obtaining a system working condition in real time, and extracting multi-dimensional state parameters including real-time flow, pressure deviation, current deviation and power deviation; the current load working condition is judged according to the pressure deviation, disturbance characteristics are analyzed by integrating all parameters, and the disturbance grade and type are determined. On the basis, robust control parameters are automatically set in combination with real-time working conditions, load conditions and disturbance characteristics of the system. And finally, performing multi-stage cooperative control on the system by using the set parameters, so that the constant-pressure water supply system is automatically set. According to the robust control automatic setting method for the constant-pressure water supply system, load working conditions and disturbance characteristics are recognized based on multi-dimensional state parameters, robust control parameters are self-set in a targeted mode, and automatic setting of the constant-pressure water supply system is achieved through multi-stage cooperative control. Therefore, the intelligent level of the constant-pressure water supply system and the adaptability in different operation environments are effectively improved.

The invention relates to the technical field of oil development, in particular to a shale oil and gas fracturing sliding sleeve capable of being opened and closed repeatedly and a using method. According to the technical scheme, a central pipe fracturing liquid inlet is formed in the upper side of a central pipe, and a reversing rail is arranged on the surface of the outer wall of the middle; a sealing cylinder sleeve and a one-way circulating valve carrier are sleeved outside the central pipe, a fracturing piston, a swivel pressing cap and a reset spring are installed in an annulus, a constant-pressure opening cavity is formed in the inner wall of the fracturing piston, a swivel is installed in the swivel pressing cap, a track pin is installed in the swivel, and the position is moved along a reversing track on the surface of the outer wall of the central pipe through the track pin. The fracturing piston moves downwards to the position of the cylinder sleeve fracturing liquid outlet under the action of pressure, the fracturing function is started, fracturing liquid is sprayed out along the cylinder sleeve fracturing liquid outlet to enter a target fracturing layer, fracturing construction of a plurality of fracturing layers can be achieved through multiple times of fracturing liquid injection and injection stopping, the fracturing sliding sleeve can be repeatedly opened and closed, and the fracturing construction efficiency is improved. And fracturing construction requirements of shale oil and gas with different layers can be met.

The utility model discloses an inerting and discharging combined safety protection device for a solid hydrogen storage tank, and belongs to the technical field of hydrogen storage and supply. The device comprises a solid hydrogen storage tank main body, a pressure and temperature sensing module, an inert gas injection system, a flameless relief device and a hydrogen treatment unit, the pressure and temperature sensing module monitors parameters in the tank in real time, when the parameters exceed a preset threshold value, the inert gas injection system injects inert gas from the lower portion of the tank body at constant pressure, the air pressure is stabilized through flow control, and meanwhile hydrogen is pumped out of an opening in the upper portion of the tank body to the processing unit; and a discharge port is formed in the side surface of the tank body and is linked with the flameless discharge device. According to the device, through the design of inerting inhibition and safe release, the potential safety hazard of overtemperature and overpressure in the solid hydrogen storage process is solved, the stability and safety of a hydrogen storage system are improved, and the device is convenient to operate and adapts to transformation of an existing solid hydrogen storage tank.

The invention discloses grinding and polishing equipment for the inner wall of a pipe workpiece. The grinding and polishing equipment comprises a rack, a workpiece rotating and supporting mechanism, a grinding mechanism, a radial feeding mechanism, an axial moving mechanism, a workpiece stabilizing mechanism and an electric control system. The grinding assembly is a flexible grinding wheel formed by splicing a plurality of arc-shaped grinding pieces, a pneumatic motor drives the flexible grinding wheel to rotate at a high speed to serve as main cutting motion, constant-pressure contact control is achieved through a radial feeding mechanism, abrasion of the grinding wheel can be compensated in a self-adaptive mode through the control mode, and it is guaranteed that the grinding pressure is stable; therefore, the reference size of the workpiece is protected to the maximum extent while the defects of the inner wall are effectively removed, the problem of size out-of-tolerance caused by uneven pressure or abrasion in traditional rigid grinding is avoided, constant-pressure, efficient and high-quality grinding is guaranteed, and the grinding and polishing efficiency and quality of the inner wall of the pipe workpiece are effectively improved.

The three-dimensional shaping cloth flattening device comprises a base, a top plate and a lifting plate, a constant-pressure flattening head is arranged on the bottom face of the lifting plate, the constant-pressure flattening head comprises a constant-pressure air chamber shell, a flexible pressurizing bag and a constant-pressure mechanism, and the flexible pressurizing bag and the constant-pressure air chamber shell are connected in a sealed mode to jointly form a closed cavity; the constant-pressure mechanism is mounted in the constant-pressure air chamber shell and is used for providing constant reference pressure for the flexible pressurizing bag; a driving mechanism is fixedly arranged on the upper surface of the top plate and used for driving the constant-pressure leveling head to move relatively. According to the three-dimensional cloth flattening device, the problem that three-dimensional cloth is not completely flattened or damaged due to uneven pressure can be solved, and the high-quality and lossless three-dimensional flattening effect is achieved.

The invention relates to the technical field of electric power engineering, in particular to a simulation method of a power station motor high-oil-pressure jacking hydraulic system, which comprises the following steps: building a high-oil-pressure jacking hydraulic simulation system which comprises a control module, a constant-pressure variable pump, a pressure release valve, a measuring element, an oil tank, an equivalent load, an equivalent hydraulic cylinder and a pressure release hole; the equivalent hydraulic cylinder is used for jacking up the equivalent load and simulating a real scene that the motor is jacked up by high-pressure oil; theoretical modeling is conducted on a frame and all parts of the high-oil-pressure jacking hydraulic simulation system; by establishing a linkage mechanism of the equivalent area, the pressure and the flow of the pressure relief hole, pressure fluctuation and compensation response during working condition conversion are accurately simulated; smooth transition between the static jacking state and the operation pressure maintaining state is achieved, and the stability and the self-adaptive capacity of the system under the variable rotating speed condition are effectively verified. Compared with traditional static simulation, the whole process of the hydraulic and mechanical coupling effect in actual operation is reflected more comprehensively.

The invention relates to an intelligent temperature control rock heat-water-force-sound-light multi-field coupling disturbance shearing device and a use method of the intelligent temperature control rock heat-water-force-sound-light multi-field coupling disturbance shearing device. A disturbance shearing mechanism composed of a trapezoid pressing rod, a constant damper and a spring is additionally arranged on the driving side of the lower shearing box. When the tangential loading shaft is propelled at a constant speed, the mechanism can convert stable linear displacement into disturbance shear load of periodic loading and unloading, so that engineering power disturbance is simulated. According to the device and the method, periodic shear disturbance is synchronously applied to a rock sample in a high-temperature seepage environment, mechanical response, seepage characteristic change, internal micro-fracture and surface full-field deformation of the rock sample are comprehensively observed, and an advanced test means is provided for researching a catastrophe mechanism of a deep rock mass under the action of multi-field coupling and dynamic disturbance.

The invention relates to a tail end constant-pressure water supply strategy adjusting method and system based on AI, and belongs to the technical field of secondary water supply.The constant-pressure water supply strategy adjusting method comprises the steps that the flow of a header pipe and real-time health state data of each running pump are periodically collected; according to the header pipe flow, the dynamic demand lift is calculated, and all feasible pump set combination strategies are generated in combination with the dynamic demand lift and the real-time health state data; the score of each candidate strategy is calculated, the candidate strategy with the highest score is used as a pump set scheduling strategy, the pump with the most matched performance is selected from candidate pump sets corresponding to the pump set scheduling strategy to serve as a frequency conversion main guide pump, and the other pumps serve as frequency conversion auxiliary pumps; according to the set minimum service pressure and the dynamic demand lift, the target pressure of a pump outlet is calculated; and according to the target pressure and the actually-collected pump outlet pressure, the rotating speed of the variable-frequency main guide pump is adjusted. The method has the beneficial effects that the power of the pump set is matched with the actual requirement, so that the operation cost is reduced.

The utility model relates to the technical field of rare earth resource exploration, in particular to a comprehensive measuring device for hydraulic parameters and various electric responses, which comprises a constant-pressure water supply component, an adjusting valve, a measuring soil column container, a collecting and measuring component, a pressure sensor, a recorder and an electric response measuring instrument. The soil column measuring container comprises a container main body, a microporous baffle plate, two current electrodes and two measuring electrodes, the water inlet end and the water outlet end of the constant-pressure water supply assembly are respectively communicated with the container main body through pipelines, and the storage and collection assembly is arranged on the pipeline between the water outlet and the constant-pressure water supply assembly; a sample cavity between the two microporous baffles in the container main body is used for filling a sample; the adjusting valve is used for adjusting the flow; the pressure sensor, the collecting and measuring assembly, the measuring electrode and the current electrode are used for measuring hydraulic parameters and flowing electric response. According to the utility model, the hydraulic parameters and various electric responses of the sample can be accurately measured, and the electric responses under different hydraulic conditions can be measured.

The invention discloses a hydraulic system for preventing reversing cutoff of a cone valve type filling industrial pump. The hydraulic system comprises a first oil pump set, a second oil pump set, a main oil cylinder set, a first pressure valve suction valve oil cylinder set, a second pressure valve suction valve oil cylinder set, a reversing valve set and a pipeline. The first oil pump set is composed of a first oil pump, a second oil pump and a first constant-pressure oil pump set. The second oil pump set is composed of a third oil pump, a fourth oil pump and a second constant-pressure oil pump set. The first pressure valve suction valve oil cylinder set comprises a first pressure valve oil cylinder and a first suction valve oil cylinder, and the second pressure valve suction valve oil cylinder set comprises a second pressure valve oil cylinder and a second suction valve oil cylinder. The reversing valve group comprises first to sixth reversing valves. According to the reversing cutoff prevention hydraulic system of the cone valve type filling industrial pump, through unique structural design and assembly configuration, the cutoff problem in the reversing process is effectively solved, continuous and stable operation of the system is ensured, and the working efficiency and reliability of the industrial pump are improved.

The invention relates to the technical field of piezoelectric liquid pumps, in particular to a piezoelectric liquid pump and a cooling device. The compression chamber and the constant-pressure chamber are arranged in a communicating mode, the piezoelectric assembly can drive the volume change of the compression chamber, a first one-way valve assembly is arranged at the communicating position of the compression chamber and the constant-pressure chamber, and the first one-way valve assembly limits fluid to flow to the constant-pressure chamber in a one-way mode; the medium inlet is communicated with the compression chamber and the outside and provided with a second one-way valve assembly, and the second one-way valve assembly limits fluid to flow to the compression chamber in one direction; and the at least two medium outlets are communicated with the constant-pressure cavity and the outside. The constant-pressure chamber is arranged between the medium outlets and the compression chamber, the first one-way valve assembly is arranged at the communicating position of the constant-pressure chamber and the compression chamber, the constant-pressure chamber can be used for buffering system pressure fluctuation and stabilizing system pressure, and synchronism and consistency of multiple strands of medium fluid output from different medium outlets are improved.

The invention provides oxygen cabin equipment and a control system, and relates to the technical field of oxygen cabins, and the oxygen cabin equipment comprises a cabin body which is provided with an observation door; the oxygen cabin main machine device comprises an oxygen generator and a main machine, the oxygen generator is electrically connected with the main machine, and the oxygen generator supplies oxygen to the cabin body through an oxygen inlet valve; the manual safety valve is used for performing manual pressure relief on the cabin body; the automatic constant pressure safety valve is installed in the cabin body, the automatic constant pressure safety valve comprises an automatic pressure detection device and a full-automatic pressure reduction and deflation device, the automatic pressure detection device is used for monitoring the pressure in the cabin body in real time, the full-automatic pressure reduction and deflation device is used for deflating the interior of the cabin body, and the automatic constant pressure safety valve is electrically connected with the host machine. Double safety guarantee is achieved through the manual safety valve and the automatic constant-pressure safety valve. Potential safety hazards caused by the fact that an existing oxygen cabin is not provided with a safety device are effectively avoided, and the safety of the oxygen cabin in the using process is guaranteed.

The invention provides a constant-pressure energy storage system and a constant-pressure expansion power generation method. Comprising a first-stage compressor motor, a first-stage compressor, a second-stage compressor motor, a second-stage compressor, a high-pressure cylinder, a low-pressure cylinder, a generator, an exhaust funnel, a hot water storage tank, a cold water storage tank, a compressed air condenser, a ground pipeline steel gas storage, a hot water storage pump, a cold water storage pump, a liquid air booster pump, an air inlet cooler, a first-stage cold water storage heater and a first-stage air cooler. The system comprises a first-stage gas-water separator, a second-stage cold water storage heater, a second-stage air cooler, a second-stage gas-water separator, a second-stage hot water storage cooler, a first-stage hot water storage cooler, a seawater preheater, a seawater heater, a compressor outlet shut-off valve, a pressure stabilization regulating valve and a liquid air supply valve. The air storage device is miniaturized, cold energy is efficiently utilized, and the system efficiency is improved.

The invention belongs to the technical field of coal bed gas exploitation and carbon dioxide geological storage, and relates to a coal bed carbon dioxide injectability evolution whole process simulation device and method, and the device comprises a true triaxial stress loading system, a temperature control system, a multi-mode gas injection system, a monitoring system, and a data processing system. The deep stratum stress state and the stratum temperature field are simulated, constant-pressure and constant-current mode carbon dioxide is injected into the true triaxial stress loading system to carry out groutability attenuation and recovery simulation, and nitrogen and pulse mode injection is switched to carry out temperature change regulation and control, phase change regulation and control and frequency change regulation and control so as to simulate groutability improvement. According to the method, a whole-process evolution mechanism of attenuation-recovery-improvement of carbon dioxide groutability is realized, meanwhile, data acquisition and permeability and stress calculation are performed through a monitoring system and a data processing system, and rapid conversion from original data to core parameters is realized; and accurate experimental data support is provided for on-site injection parameter optimization and regulation and control technology research and development.

The invention discloses a device and method for testing the thermal shrinkage rate of a diaphragm, and the method comprises the steps: S1, cutting a diaphragm into a preset size in advance, and placing the diaphragm on a lower loading plate according to the position of a reference line; s2, a dyeing auxiliary plate is placed, and a dyeing agent is used for dyeing; s3, taking down the dyeing auxiliary plate and horizontally placing an upper pressing plate; s4, applying a preset pressure, simulating the stress condition of the diaphragm in the battery cell, maintaining a constant pressure, assembling the bolt, and fixing a torque; s5, placing in a temperature control box, heating to a preset temperature, and standing; s6, the camera captures and records changes of multiple groups of region areas and relative positions of diaphragm dyeing along with time, and the total shrinkage rate and the shrinkage rates of different dyeing regions are calculated respectively; and S7, collecting the real-time shrinkage rates of multiple groups of positions of the diaphragm at different temperatures, judging whether the local shrinkage rates of the whole diaphragm and each region are qualified or not, and providing reference for subsequent adjustment of a coating formula.

According to the granular material crushing resistance testing system and method based on dynamic water pressure loading, the high-precision dynamic water pressure loading system, the transparent closed testing cavity and the multi-modal data acquisition and analysis system are integrated, so that dynamic mechanical property testing of a granular material in a simulated actual hydraulic environment is realized; the dynamic water pressure loading system is used for generating continuous and adjustable water flow pressure and vividly simulating dynamic hydraulic impact and alternating stress in an actual working condition; the transparent test cavity is combined with a high-speed camera shooting technology to capture the particle deformation and crushing process in real time, a high-sensitivity pressure sensor monitors critical crushing pressure synchronously, and dual-mode data association analysis realizes visualization of the particle crushing process and collaborative accurate judgment of a crushing critical point for the first time; the device supports dual modes of stepped pressurization and constant-pressure loading, can output a single-particle crushing resistance value, can also count the batch particle breakage rate, breaks through the limitation of a traditional static test, and remarkably improves the goodness of fit between a test result and an actual working condition.

Systems and methods of the invention generally relate to prolonging viability of bodily tissue, especially lung tissue, through the use of an expandable accumulator to maintain a constant pressure within the lumen of the organ even during external pressure fluctuations due to, for example, flight. Systems and methods may include prolonging donor organ viability in storage through the use of an organ container that mimics the geometry and orientation of the organ in vivo.

A chromatographic column packing machine comprises a machine box, a pneumatic pump is arranged in the machine box, a liquid outlet is formed in the side wall of the machine box, the liquid outlet is connected with the pneumatic pump through a pipeline, and the chromatographic column packing machine is characterized in that a pulsation damper is arranged on the pipeline. The flow pulsation damper has the beneficial effects that the flow pulsation damper is additionally arranged at the output end of the pneumatic pump, so that the flow pulsation can be effectively inhibited, the flow is kept stable while the column filling machine outputs displacing liquid at constant pressure, the column filling effect is improved, and the filling qualification rate of a chromatographic column is improved.

The invention relates to a method for regulating and controlling porous carbon for capacitive desalination by utilizing negative pressure pulse flow. The method specifically comprises the following steps: placing the porous carbon in a heating furnace, continuously contacting the porous carbon with airflow at a high temperature, rapidly reducing the absolute static pressure of the gas in the furnace to be less than or equal to 85kPa every 8-100min during the contact period, then restoring to be close to the initial static pressure to form negative-pressure pulse airflow, and intermittently introducing the pulse airflow in this way until the appropriate contact time is reached. According to the invention, the specific surface area, the total pore volume and the capacitance desalination amount of the pore-containing carbon can be improved without increasing energy consumption; compared with constant-pressure airflow modified porous carbon, the reaction temperature, the reaction time or the gas consumption can be reduced under the condition of reaching the same carbon index.

Systems and methods of the invention generally relate to prolonging viability of bodily tissue, especially lung tissue, through the use of an expandable accumulator to maintain a constant pressure within the lumen of the organ even during external pressure fluctuations due to, for example, flight. Systems and methods may include prolonging donor organ viability in storage through the use of an organ container that mimics the geometry and orientation of the organ in vivo.

The invention discloses coal rock hydraulic fracturing crack dynamic evolution monitoring equipment and method, and the method comprises the steps: firstly applying three-way independent stress to a coal rock test piece through a true triaxial loading module, and simulating an underground true stress environment; then an ultrasonic excitation module is started, an ultrasonic physical field excitation environment is applied to the coal rock test piece, and development of microcosmic fractures in the coal body is promoted; and the high-pressure pump injection module is started, high-pressure water is injected into the coal rock test piece at constant flow or constant pressure, and more efficient hydraulic fracturing is achieved under excitation of the ultrasonic physical field. In the whole process, the acoustic emission monitoring module captures an elastic wave signal generated by coal rock fracture in real time, and the microcrack initiation position is accurately positioned; the CT scanning module obtains the three-dimensional expansion morphology of the macroscopic crack through scanning; and finally, through a multi-physical field cooperative loading and multi-scale monitoring technology, the whole-process dynamic representation from microcrack initiation to macroscopic crack penetration is realized, and a theoretical support and a technical means are provided for efficient development of coal bed gas.

The invention relates to the technical field of water turbine generator set installation and maintenance, and discloses an intelligent water turbine runner test device and method, and the device comprises a hydraulic control unit which is used for providing and adjusting pressure oil for a constant-pressure cavity, an opening cavity and a closing cavity of a water turbine runner; and the main controller is used for receiving a user instruction, calling an automatic control logic according to a selected test item, driving the hydraulic control unit to execute a corresponding oil path action, and receiving and processing the cavity pressure of the runner hub, the servomotor stroke and the blade rotation angle parameter which are acquired in real time so as to automatically complete the runner test item specified by the national standard. The test process is automatically executed through the main controller, and frequent manual operation is replaced by simple clicking, so that the labor intensity of operators is greatly reduced.

The invention discloses an ultra-low temperature refrigerator self-adaptive temperature control method based on fuzzy control, and relates to the technical field of intelligent control and industrial automation. Initializing target temperature, pressure and flow, acquiring data by using a high-precision sensor, and performing Kalman filtering to reduce noise; a fuzzy control rule base is constructed, the temperature deviation and the change rate serve as input, and the refrigerating / heating power adjusting quantity is deduced and output; a compressor, a heating pipe and an expansion valve are adjusted according to the reasoning result, and fine adjustment is switched when the deviation is smaller than 0.5 DEG C; dynamically adjusting the pressure to avoid boiling or cavitation of the secondary refrigerant, monitoring the liquid level of the constant-pressure tank and supplementing liquid; an interference compensation model is established, the system state is monitored in real time, faults are recorded, and pharmacy, military industry and other scenes are adapted. The temperature control precision and stability of the ultra-low temperature refrigerator are improved, pressure-temperature cooperative control is achieved, the interference influence is offset, it is guaranteed that a secondary refrigerant is stable, multi-load and fault switching are adapted, the high-precision requirements of pharmacy and the military industry are met, and the shutdown risk is reduced.

The invention discloses a method for testing compression creep performance of a metal material under a constant-temperature condition, relates to the technical field of high-temperature performance testing of metal materials, and aims to solve the problem of inaccurate creep measurement at a constant temperature. According to the invention, a full-process compression creep performance test method of constant temperature control, loading compensation and strain correction is constructed, the test accuracy and the result consistency of the metal material in a constant temperature environment are improved, closed-loop control is realized through actual measurement temperature, time delay prediction and retaining ring heating are introduced, the constant temperature stability is ensured, and the test accuracy is improved. A micro-stepping compensation mechanism is adopted to maintain constant pressure stress, a loading state is automatically recovered after interruption, then system deformation is deducted through main and auxiliary link cooperation and a compliance template, strain measurement precision is ensured, distortion caused by boundary friction is overcome in combination with end face stick-slip detection and equivalent strain correction, and the accuracy of strain measurement is improved. Finally, automatic output of performance parameters is achieved through steady-state segment extraction and anomaly recognition, and the effectiveness, reproducibility and engineering applicability of test data are guaranteed.

The invention belongs to the field of ocean instrument metering calibration, and particularly relates to a temperature compensation type ocean pressure sensor calibration device and method, and the device comprises a standard constant temperature system, a standard constant pressure system, a data collection system, and a data processing unit. The standard constant temperature system is used for providing a controllable and monitorable constant temperature environment for the calibrated sensor; the standard constant pressure system is used for providing a controllable standard pressure source; the data acquisition system synchronously acquires temperature, standard pressure and sensor output signals; and the data processing unit establishes a temperature-pressure mathematical relationship model based on the acquired data and generates temperature compensation correction parameters. According to the calibration method, a plurality of standard pressures are applied at different temperature points, synchronous data are acquired, and a temperature compensation function is obtained through fitting by using a least square method, so that high-precision compensation of the ocean pressure sensor in a wide temperature gradient environment is realized. The measurement precision of the ocean pressure sensor in the temperature range is effectively improved, and the method is suitable for high-precision scenes such as ocean hydrological observation.

The invention discloses a control method, a control system and related equipment for constant temperature, constant oxygen and constant pressure. The control method comprises the following steps: acquiring temperature data, oxygen concentration data and pressure data in a cabin body in which an oxygen cabin mainboard is positioned; determining a current working stage according to the pressure data and a preset target pressure value; in the boosting stage, the opening degree of an air inlet valve of a control cabin, the rotating speed of an air compressor and the oxygen production amount of an oxygen generator are synchronously increased; in the pressure stabilizing stage, at least two of the opening degree of an exhaust valve, the opening degree of an air inlet valve, the rotating speed of an air compressor, the oxygen production amount of an oxygen generator and the temperature adjusting capacity of an air conditioner of the cabin are adjusted at the same time according to the temperature data, the oxygen concentration data and the pressure data; if so, controlling the oxygen generator to be closed, and controlling the opening degree of the exhaust valve and the rotating speed of the air compressor to synchronously change. According to the invention, higher-precision pressure control, oxygen concentration control and temperature control can be realized, and the stability of pressure, oxygen concentration and temperature is ensured.

The utility model discloses a polishing device for metal casting production, which is used for polishing the outer wall of a cylindrical metal casting and comprises a fixing seat and a bearing seat fixedly mounted on the fixing seat, an annular groove is formed in the fixing seat, a polishing mechanism capable of moving in the annular groove is movably mounted in the annular groove, and the bearing seat is fixedly mounted on the fixing seat. The bearing seat is composed of a plurality of bearing pipes with square sections, and the bearing pipes are evenly arranged around the circle center of the annular groove and located on one radius line of the annular groove. According to the grinding device for metal casting production, simple and reasonable structure matching is adopted, a high-automation grinding mechanism replaces conventional manual grinding, the grinding efficiency is improved while the grinding effect is guaranteed, the grinding head keeps constant-pressure contact in the whole process under the matching of the pressure sensor and the telescopic rod, and the grinding efficiency is improved. And the polishing smoothness and uniformity are higher and more accurate.

The utility model discloses a novel hydraulic control system of household garbage dry-wet classification equipment, and belongs to the field of hydraulic control. The hydraulic control system comprises a large variable pump connected and driven by a first motor, a small variable pump connected and driven by a second motor, a duplex vane pump connected and driven by a third motor, a cooling circulating pump connected and driven by a fourth motor, a pressure control valve group, an extrusion roller feeding control valve group, a cooperative control valve group, an extrusion oil cylinder and a low-speed large-torque hydraulic motor; the device comprises a feeding oil cylinder, a door blocking oil cylinder, a door lifting oil cylinder, a push-pull box oil cylinder, a box locking oil cylinder, an oil return filter, a circulating filter, an air cooler and an oil tank. According to the utility model, the multifunctional control variable pump with constant power and remote constant-pressure control is adopted, so that the device is suitable for the extrusion working condition of household garbage dry-wet classification equipment, the working efficiency is higher, and small-load high speed and large-load low speed are easier to realize; and the system is more energy-saving and smaller in heat generation.

The utility model discloses a constant pressure switch and drainage system for a urine bag, which comprises a shell, the shell comprises a main shell, a front cover body and a rear cover body, the main shell is provided with an input port and an output port, a liquid inlet cavity and a liquid drainage cavity are arranged in the shell, the input port is communicated with the liquid inlet cavity, the output port is communicated with the liquid drainage cavity, and the liquid drainage cavity is communicated with the front cover body. A movable sealing plate is arranged between the liquid inlet cavity and the liquid outlet cavity, the liquid inlet cavity and the liquid outlet cavity are communicated or isolated through movement of the sealing plate, and a spring is arranged between the sealing plate and the inner wall of the front cover body and / or the inner wall of the rear cover body. The scheme provides the constant pressure switch capable of protecting the urination function.