405 results about "Pressure rise" patented technology

The invention relates to the technical field of automatic control, in particular to an automatic control method of a BOG low-temperature recovery system for a storage tank for an LNG (liquefied natural gas) ship, which comprises the following steps: acquiring BOG pressure fluctuation data and temperature difference trend, analyzing pressure rise rate and cooling efficiency change, identifying a pressure peak value and a cooling lag section, screening a low-efficiency section and marking an optimization unit. And identifying an energy matching degree, analyzing energy loss distribution, identifying an over-limit node and a fault signal, and obtaining an energy and fault synchronous control table. According to the system, through real-time data monitoring and intelligent analysis, the BOG recovery process can be accurately controlled, energy circulation and cooling treatment can be optimized, the efficiency of a low-temperature recovery system can be improved, BOG pressure and temperature difference changes can be monitored, pressure fluctuation and cooling lag can be analyzed, continuous improvement of condensation efficiency can be ensured, control parameters can be accurately adjusted, energy loss is avoided, and the energy efficiency of equipment can be improved; energy consumption and equipment fault management are optimized, and efficient and safe operation of the low-temperature recovery system is ensured.

The invention discloses a liquid hydrogen container heat leakage prediction and boost characteristic detection method and system. The method comprises the following steps: establishing a three-dimensional heat flow field model of a liquid hydrogen container; calculating the heat flow density of a gas-liquid interface based on the three-dimensional heat flow field model so as to adjust the liquid hydrogen evaporation capacity; total heat leakage is obtained through finite element simulation and experimental data collaborative calibration; calculating a static evaporation rate according to the total heat leakage; establishing a nonlinear mapping model of the static evaporation rate and the boost rate through a response surface regression method; the wall temperature distribution of the liquid hydrogen container is monitored in real time, thermophysical parameters are calibrated through the LSTM neural network by adopting a dynamic calibration algorithm, and the output result of the three-dimensional heat flow field model is corrected. By establishing a three-dimensional heat flow field model of the liquid hydrogen container, determining a nonlinear response relationship between the evaporation rate and the pressure rising rate of the liquid hydrogen container, and constructing a cloud-edge collaborative detection system, the heat leakage performance of the liquid hydrogen container is accurately predicted, and efficient pressure rising rate detection is realized.

Low-pressure oil enters an inlet of a proportional overflow valve, the pressure of a low-pressure system is controlled by the proportional overflow valve, pressure oil on the low-pressure side acts on a plunger control cavity of the hydraulic control overflow valve through a pressure stabilizing damper and a one-way valve, and hydraulic pushing force generated by a plunger is transmitted to an overflow valve steel ball through a disc spring; when the force obtained by multiplying the ultrahigh pressure of the inlet of the hydraulic control overflow valve by the action area of the steel ball is equal to the pushing force of the plunger, the steel ball of the overflow valve is opened to start overflowing, and the overflow pressure of the ultrahigh pressure system can be controlled by adjusting the pressure of the proportional overflow valve of the low-pressure system. The external control type ultrahigh-pressure proportional pressure regulating valve can be used for pressure regulation of a hydraulic system with the pressure being 200 MPa or above and can be used as a proportional overflow valve of an ultrahigh-pressure hydraulic system. By arranging a hydraulic loop of two auxiliary oil ports of the external control type ultrahigh pressure proportional pressure regulating valve, the pressure rising one-way proportional regulating function, the pressure unloading function and the pressure rising / falling two-way proportional regulating function of an ultrahigh pressure system can be achieved.

The invention belongs to the technical field of valves, and particularly discloses a self-pressure-control cut-off ball valve which comprises a valve shell, a sealing cavity is formed in the middle of the interior of the valve shell, a spherical valve element is rotationally arranged in the middle of the inner wall of the sealing cavity in a sealed mode, the middle of the spherical valve element is in a through opening shape, and an indicating groove is formed in the bottom of the valve shell. When pressure in a pipeline rises, the transmission assembly can be triggered in the valve shell to work so that the spherical valve element can rotate, then the valve shell is opened and conducted, the transmission assembly can be further driven to work along with pressure rising, and when the maximum pressure value of the valve is reached, the transmission assembly can be driven to rotate, so that the transmission assembly can be driven to rotate. At the moment, the opening degree of the spherical valve element in the valve shell is in the maximum state, the limiting assembly is triggered to limit the transmission assembly at the moment, the situation that the spherical valve element continues to rotate, and consequently the opening degree is decreased is prevented, and opening and closing of the valve can be automatically adjusted according to changes of the pressure in the pipeline.

The utility model relates to the technical field of detection devices, and discloses a collection device for gas detection, which comprises a shell, a sliding plate is slidably mounted in the shell, two rectangular columns are fixedly mounted at the top of the sliding plate, tooth grooves are respectively formed in the right sides of the two rectangular columns, a mounting groove is formed in the right side of the shell, and the tooth grooves are fixedly mounted in the mounting groove. A rotating rod is rotationally mounted on the inner wall of the mounting groove, and the outer wall of the rotating rod is fixedly sleeved with a door plate and a first gear. When a rectangular column moves upwards, linear motion is efficiently converted into rotation motion of a gear through a meshing mechanism of a tooth groove and the gear, and it is ensured that a door plate can rapidly and stably rotate so as to respond to internal air pressure changes. The rotating angle and speed of the door plate can be accurately controlled, and when too much gas is collected in the shell and the gas pressure rises to a certain degree, the door plate can automatically rotate to open the gap.

The invention discloses a multi-mode cooperative intelligent forming control system, particularly relates to the field of production strategy control, and is used for solving the problems that a control strategy is difficult to dynamically adjust according to different mold characteristics in an existing mold forming process, and intelligent matching cannot be realized due to forming period section division. A preloading module is used for collecting mold press-fitting displacement parameters and a thermal response curve in a forming period, a response hysteresis analysis module is used for analyzing stress response and structural deformation absorption capacity of a mold, a thermal inertia analysis module is used for identifying a mold thermal inertia window, and a section division strategy space of the current forming period is jointly constructed; and time sequence boundaries of the pressure rising section, the pressure stabilizing section and the cold conversion section are set through the control module, and accurate control over the forming process is achieved. The system further constructs a biaxial parameter space based on a hysteresis attribute and a thermal inertia window through a strategy space updating module, executes strategy updating, and forms a strategy adjustment network capable of adapting to the multi-mode collaborative processing process.

The invention relates to the technical field of ascites drainage, in particular to an ascites drainage device which comprises a puncture tube, the output end of the puncture tube is fixedly connected with a one-way valve, the output end of the one-way valve is fixedly connected with a separation tube, a drainage opening is formed in the bottom of the separation tube, and the output end of the drainage opening is fixedly connected with a drainage tube. The output end of the drainage tube is fixedly connected with a liquid accumulation bag, a filter cartridge is arranged in the separation tube, and the input end of the filter cartridge is communicated with the input end of the separation tube. The spiral flow deflectors which are uniformly arranged along the central axis are arranged at the input end of the filter cartridge, so that ascites can be guided to form a spiral flowing state, and solid substances are always kept in dynamic distribution of'spirally advancing along the wall 'by virtue of centrifugal force; meanwhile, when the filter cartridge is blocked and the pressure rises to a preset value, the second T-shaped piston rod can extrude the titanium alloy spring to slide, so that ascites enters the hole-free groove to expand the internal space of the filter cartridge, the pressure is balanced, and time is bought for cleaning blockages.

The invention discloses an engine multi-vehicle-type adaptive NVH quality optimization method and system, and belongs to the technical field of automobile engine debugge.The method comprises the steps that after an engine is installed on a to-be-adapted vehicle, vehicle working condition data are collected in real time, the vehicle working condition data comprises a vehicle speed, an accelerator opening degree, an engine rotating speed, a gear, a hydraulic torque converter locking state and an engine oil temperature signal; the vehicle working condition data is compared with the working condition of the engine noise sensitive working condition, and whether the engine noise sensitive working condition is entered or not is recognized; when the engine has the noise sensitive working condition, an NVH control strategy embedded in an engine electronic control unit is activated; the NVH control strategy comprises adjustment of an engine ignition angle and oil injection parameters; the engine is controlled according to the ignition angle optimization control instruction and the oil injection parameter optimization instruction; and when the vehicle runs out of the working condition of the noise sensitive working condition of the engine or gear shifting is completed, the conventional combustion control logic is recovered. And the rising rate of the pressure in the cylinder is effectively reduced, so that the structural knocking noise within the range of 150-600Hz is inhibited.

The invention relates to the technical field of transportation devices, and discloses a coated glass carrying control method and system, and the method comprises the steps: respectively collecting surface reflection spectrum data, dimension specification parameters and carrying force arm information; extracting film layer combination characteristics, and carrying out bearing capacity calculation by combining dimension specification parameters and carrying force arm information to obtain a theoretical stress extreme value; acquiring a pressure rise rate and a steady-state leakage rate, and performing airtight characteristic inversion on the coated glass based on the pressure rise rate and the steady-state leakage rate to obtain an interface adsorption efficiency value; carrying out constraint boundary fusion on the theoretical stress extreme value and the interface adsorption efficiency value to obtain a double constraint envelope; time sequence deduction is conducted on the mechanical arm based on double constraint envelope, and a space motion time sequence is obtained; a self-adaptive inertia carrying instruction is generated based on the space motion time sequence; the carrying stability of the coated glass can be improved.

An automated vacuum container can include a main body, lid, valve(s), automated pump, processor, and input device(s). The main body can have an outer housing, sealable opening, and inner volume. The lid can be removably coupled to the main body to cover the sealable opening and can include air passage(s) therethrough. Valve(s) can control airflow through air passage(s). as air is pumped from the inner volume to form a vacuum. The processor can operate in sleep and awake modes, receive input(s), and control pump operation. An input device can send a wake up signal to the processor based on an environmental condition change. Pressure sensor(s) can detect pressure within the inner volume and provide input to the processor. The pump can be stopped when pressure is sufficiently low and restarted when pressure rises above a threshold level, such as when stored perishable item(s) outgas under vacuum within the inner volume.

The invention relates to the technical field of product detection, in particular to a plastic mold production quality detection method and system. The method comprises the following steps: acquiring in-mold pressure data of each cavity of the multi-cavity mold in a plastic injection molding process and mold wall temperature data of a cooling stage; determining a pressure rise acceleration curve based on the in-mold pressure data of each cavity; based on the pressure rising acceleration curve and a preset fluctuation threshold value, a filling fluctuation index of the melt filling stage is determined; based on the mold wall temperature data, a cooling hot spot index of a cooling stage is determined; and comparing the filling fluctuation index with a filling fluctuation threshold value, and comparing the cooling hot spot index with a cooling hot spot threshold value to obtain a detection result of the production quality of the plastic mold. The objective of the invention is to solve the problem of early cracking, deformation or structural failure of a product caused by difficulty in accurately detecting the product produced by a plastic mold in the prior art.

The invention provides a stall boundary prediction method and device of a gas compressor, electronic equipment and a storage medium, and relates to the technical field of pneumatic design of gas compressors. The method comprises the steps that through-flow calculation is conducted on the gas compressor, and a through-flow calculation result is obtained; according to the through-flow calculation result, stage static pressure rise coefficients and diffusion factors of different blade height sections of the gas compressor are determined; according to the stage static pressure rise coefficients and the diffusion factors of the different blade height sections, the first stall section is determined from the different blade height sections; determining a limit value which can be reached by the stage static pressure rise coefficient of the first stall section; and in response to the fact that the stage static pressure rise coefficient of one stage on the first stall section reaches the limit value, it is predicted that the compressor reaches the stall boundary. Therefore, according to the scheme, the prediction precision and the prediction speed of the stall boundary of the gas compressor are improved, so that rapid and accurate prediction of the stall boundary of the gas compressor is realized.

The invention provides a blowout control method based on wellhead methane adsorption, which comprises the following steps of: compounding a methane adsorption material with other necessary drilling fluid additives to form high-density composite well killing fluid in a key stage (namely when well control dangerous conditions such as overflow or well kick occur) before blowout; and then, at the position 100-200 m below a well mouth, the composite well killing fluid is injected into a shaft through special well killing fluid injection equipment according to preset injection parameters. According to the method, slipping and rising of methane bubbles invading a shaft are effectively restrained through the high density of well killing fluid, meanwhile, methane gas in the shaft is adsorbed in real time through a methane adsorption material compounded in the well killing fluid, gas column expansion and pressure rising are effectively controlled in the early stage of gas invasion through the dual-action mechanism of density suppression and active adsorption, and the gas invasion safety is effectively improved. Therefore, blowout is prevented or development of blowout is restrained.

The invention relates to a hydrogen-diesel oil dual-fuel single-cylinder engine heavy-load working condition combustion control system and method, belongs to the technical field of engines, and is characterized in that an air inlet pressure sensor is mounted near an air inlet valve, a control valve is mounted in an air inlet channel, an electric supercharger and an intercooler are connected to the other air inlet channel in series, and a temperature sensor is mounted; a pressure sensor, a hydrogen sprayer and an oil sprayer are installed in the combustion chamber, and the hydrogen sprayer, the oil sprayer, the electric supercharger, the control valve, the air inlet pressure sensor, the pressure sensor, the intercooler and the temperature sensor are connected with a vehicle-mounted computer at the same time. The control over the pressure rising rate and the pressure fluctuation of the hydrogen-diesel oil dual-fuel single-cylinder engine under the large-load working condition is achieved by adjusting the air inlet supercharging pressure and the fuel injection control strategy, and the problem of abnormal combustion under the large-load working condition is solved.

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

The invention relates to a linked polyethylene insulated power anti-interference control cable which sequentially comprises a wire core, a filling layer, a shielding layer, an armor layer and a rubber layer from inside to outside and further comprises a machine shell. The first air pressure sensor outputs a detected air pressure rising signal, and the air pressure rising signal is essentially a key indirect temperature abnormity indication signal. As the temperature sensor directly reflects that the temperature of the local armor layer area exceeds the threshold temperature of particle decomposition, an external system sends out an overheat alarm after receiving the signal, and an operator is prompted to troubleshoot a fault point. The thermal decomposition particles filled in the metal tube in the armor layer are utilized to convert the local high temperature of the armor layer / rubber layer junction area which is difficult to directly measure into visible gas generation amount change, and then the visible gas generation amount change is converted into an accurate gas pressure signal through the closed cavity.

The invention relates to a production string leakage positioning method. The method comprises the steps that an initial pressure stable value of an oil sleeve annulus and a pressure fluctuation value of the oil sleeve annulus are obtained; calculating a pressure fluctuation threshold value of the oil jacket annulus according to the initial pressure stable value and the sensor monitoring error; the pressure fluctuation value is compared with a pressure fluctuation threshold value, and whether a new leakage point appears or not is judged; if no new leakage point appears, the depth of the leakage point is calculated according to the U-shaped pipe pressure balance principle, and a positioning result is obtained; and operating oil pressure fluctuation based on a positioning result to obtain an oil pressure fluctuation calculation value, and comparing the oil pressure fluctuation calculation value with an actually-monitored oil pressure fluctuation monitoring value to judge the positioning reliability. According to the method, the leakage point position is determined and the positioning result is verified by judging the state of the leakage point of the production pipe column in advance, so that the positioning precision is improved, the leakage pressure rising phenomenon of the production pipe column is effectively controlled, and the working efficiency is improved.

The invention is suitable for the technical field of vehicle part testing, and provides a firmness testing system for new energy automobile part manufacturing, which comprises a protection box, a force storage part and an automobile anti-collision frame, a support frame is fixedly mounted at the top of the force storage part; a rotating part is rotationally arranged on the supporting frame; a pull rope penetrates through the peripheral side surface of the Z-shaped pipe in a sliding manner; an impact ball matched with the conical cover is fixed at one end of the pull rope; the end part of the first L-shaped plate is fixedly connected with a force unloading part; the force unloading part comprises a U-shaped plate; according to the system, an impact ball is launched by inflating and boosting the force storage part to carry out a simulation impact test on the automobile anti-collision frame, the launching angle of the impact ball is adjusted by controlling the rotation of the rotating part, and the launching position of the impact ball is adjusted by controlling the movement of the sliding sleeve. Therefore, impact scenes from different directions in the actual driving process are simulated, the diversity of firmness test data is increased, and the test accuracy is improved.

The utility model discloses an integrated pressure reducing valve which comprises a pressure reducing valve body and an air inlet formed in the upper end of the pressure reducing valve body. When equipment is used, when the system gas pressure fluctuates or the system is damaged to cause pressure rise, the pressure of the second-stage pressure reduction part rises accordingly, when the critical value of the pressure relief valve is reached, the pressure relief valve element is opened, gas is discharged through the pressure relief valve, the system pressure is reduced, breathing openings are formed in the first-stage pressure reduction part and the second-stage pressure reduction part respectively, and when the pressure relief valve works, the pressure relief valve element is opened. The first-stage valve rod and the second-stage valve rod move, the volume of a cavity between two sealing faces of the valve rod combination can change accordingly, gas in the cavity can flow in and flow out, a breathing opening is provided with a waterproof breathable filtering device, and the situation that impurities pollute the cavity and sealing elements, and consequently the pressure reducing valve fails is avoided. The integrated pressure reducing valve is used for monitoring the gas pressure of the second-stage pressure reducing part, and through the arrangement of the two-stage pressure reducing function, the integrated pressure reducing valve is stable in performance and high in durability.

The invention belongs to the technical field of transformer protection, and particularly discloses a transformer safety protection device. A trigger valve body is arranged on the main body; the isolation shell is arranged outside the main body, and a blocking area is formed between the isolation shell and the main body; the connecting rod frame is slidably arranged in the blocking area; the explosion suppressant storage tank is arranged on the inner wall of the isolation shell; and the trigger valve body is arranged to trigger the connecting rod frame to open the explosion suppressant storage tank when the air pressure in the main body rises. When air pressure rises due to electric arcs, short circuits and the like generated in the transformer due to faults, the trigger valve body is pushed by the internal air pressure to act, then the connecting rod frame is driven to slide in the blocking area, the releasing mechanism of the explosion suppressant storage tank is triggered in the movement process of the connecting rod frame, the explosion suppressant is rapidly sprayed to the main body, and suppression of initial faults is achieved. According to the protection device, active protection is achieved through air pressure triggering, faults are restrained in the germination stage, and meanwhile high-temperature oil gas generated by the faults can be preliminarily isolated through an isolation area formed by the isolation shell and the main body.

The invention provides an adsorption pressure return type blowout control method, which comprises the following steps: intervening when well control abnormity occurs at the beginning (such as overflow precursor), compounding a methane adsorbent and a conventional drilling fluid additive to prepare high-density composite well control fluid, and injecting the high-density composite well control fluid into a shaft by a special device at a position 100-200m below a wellhead according to preset displacement and pressure parameters. According to the method, bubbles in a shaft are adsorbed through an adsorbent, the slippage speed and the gas phase volume fraction are reduced, and the synergistic effect of static pressure constraint and active adsorption is achieved. Therefore, back pressure fluctuation can be stabilized in the early stage of gas cut, gas column expansion and pressure rising are limited, the risk of pressure leakage and secondary eruption is reduced, the purpose of preventing or restraining blowout is achieved, and the gas cut blowout prevention device is suitable for complex working conditions such as fractured stratums, deep water, high temperature and high pressure and narrow-density windows.

The invention relates to the technical field of emptying valves, and discloses a diaphragm type high-temperature-resistant emptying valve which comprises a valve seat, a plurality of valve bodies are fixedly connected to the bottom of the valve seat, a connecting plate is fixedly connected to the top of the valve seat, a diaphragm is fixedly connected to the interior of the connecting plate, a shell is fixedly connected to the top of the connecting plate, and a fixing ring is fixedly connected to the inner diameter of the shell. A sliding column is slidably connected to the inner diameter of the fixing ring, an extrusion part is fixedly connected to the bottom end of the sliding column, a first spring is fixedly connected between the extrusion part and the fixing ring, and a second spring is arranged in the first spring. In the normal state, the first spring and the second spring abut against the extrusion piece to be tightly attached to the valve seat, when the pressure rises, the first spring is compressed firstly, the extrusion piece moves upwards, the valve is opened, at the moment, the first spring provides small resistance, the valve can respond to small overpressure rapidly, and the compression amount of the first spring is increased along with continuous rising of the pressure.

The application provides a delay opening toe sleeve, comprising: a hollow pipe, a lower end of which is configured as a lower joint and is provided with a first communication hole; a sealing sleeve and a communication sleeve sleeved on the hollow pipe, a first annular space and a second annular space being respectively formed between the sealing sleeve, the communication sleeve and the hollow pipe, the communication sleeve being provided with a second communication hole aligned with the first communication hole; a pressure transmission sleeve arranged between the sealing sleeve and the communication sleeve, the pressure transmission sleeve being provided with a pressure transmission hole; a delay medium and a sleeve arranged in the second annular space; a rupture disc assembly arranged in a side wall of the lower joint, a radial outer side of the rupture disc assembly being provided with a gap in communication with the second annular space; wherein the sleeve blocks the first communication hole and the second communication hole in an initial state, and the pressure transmission hole is closed, the delay opening toe sleeve is configured to make the rupture disc assembly break when a wellbore pressure rises to a test pressure value, and to open the delay opening toe sleeve through the sleeve and the delay medium.

The invention relates to the field of valve structures, in particular to a fluid control system integrating a gate valve and a pressure reducing valve. The control system comprises a pressure reducing valve, a gate valve, a pilot valve device and a brake separating device. The brake separating device is linked and synchronously prevents upstream fluid from entering a flow guide cavity of the pilot valve device before the pilot valve device is adjusted, the high-pressure impact risk is eliminated, and a zero-pressure calibration environment is established. The pilot valve device serves as a pressure adjusting center, the swing piece of the pilot valve device swings around the rotating shaft under driving of fluid pressure, the first plunger and the second plunger are synchronously driven by the connecting rods on the two sides to axially and reversely move, and when high-pressure fluid pushes the first plunger to move into the flow guide cavity to open a high-pressure port, the high-pressure port is opened. And the second plunger is linked to move to synchronously open the low-pressure port to form a pressure relief channel. When the output pressure is increased abnormally, the fluid drives the second plunger in the reverse direction to press the sealing face tightly, the high-pressure port is locked in a linkage mode through the swing piece, the action is in linkage with the diaphragm of the pressure reducing valve to drive the valve clack to close the valve port, and overpressure cutting-off and dynamic pressure balance are achieved.

The invention relates to the technical field of display module packaging, and discloses an OLED display module packaging structure which comprises a laminating mechanism, a placing assembly is fixedly mounted on the inner wall of the laminating mechanism, a driving assembly is mounted on the inner wall of the laminating mechanism, an electric telescopic rod is started to generate back-and-forth contraction force, a first roller is pushed to roll on a substrate, and a second roller is driven to roll on the substrate. Through the jacking assembly and the extruding assembly, the first roller descends to increase the pressure on the substrate, after the first roller rolls every time, the pressure applied to the first roller is gradually increased, the first roller rolls at low pressure, large-size bubbles on the surface of the substrate are driven from the center area to the edge, and after the pressure is increased, the bubbles are pushed to migrate to the edge of the substrate in the movement direction of the first roller. And finally, the pressure is increased again, the roller I compacts the coating glue between the cover plate and the base plate, so that the coating glue flows uniformly, the cover plate and the base plate are tightly attached, and bubble residues in the cover plate and the base plate when the cover plate and the base plate are pressed are effectively prevented.

This invention relates to the field of research on the operational characteristics of overpressure relief devices, and particularly to an experimental device for measuring the operational characteristics of overpressure relief devices under water hammer conditions. The device includes: a high-pressure air compressor, a frame, a piston accumulator, a quick-opening device, a high-pressure test assembly, and a high-frequency dynamic pressure sensor. This invention enables the measurement of operational characteristics under different pressure rise rate loads caused by water hammer phenomena on a test bench, providing an experimental platform for the research on the operational characteristics of overpressure relief devices under high pressure rise rates. The overall device is simple, quick, and stable. It effectively solves the problem of applying high pressure rise rate loads in current overpressure relief device operational characteristic measurement tests, overcomes the danger of using combustible gas explosions as pressure sources in existing operational characteristic measurement tests, and overcomes the shortcomings of existing test methods, such as long testing times, the need to calculate gas explosion pressure, and the difficulty in accurately controlling the pressure rise rate.

To provide a method for continuously casting a steel with which the natural opening ratio of a long nozzle can be improved by restraining the pressure rise in the long nozzle at the time of changing a ladle.SOLUTION: A molten steel flow rate control device (5) for controlling a flow rate of molten steel poured from a ladle (1) into a tundish (2) is closed, and a tip portion of a long nozzle (9) for pouring the molten steel from the ladle (1) into the tundish (2) is immersed in the molten steel in the tundish (2) with a filler (4) filled in a molten steel outflow hole (3) of the ladle (1).SELECTED DRAWING: Figure 4

This invention discloses a dynamic pressure-based method for testing and analyzing hammer shock waves in aero-engines, belonging to the field of aero-engine testing and structural strength design. The method first uses a surge-induced pressure method to generate hammer shock waves at the engine inlet. Based on the flow field characteristics of the air intake outlet section (AIP section) during surge, dynamic total pressure and static pressure measuring points are arranged in a combination of circumferential and radial directions. Pressure signals are synchronously recorded using a high-speed data acquisition system, and four characteristic parameters—surge overpressure, overpressure ratio, loading time, and pressure rise rate—are defined to quantitatively analyze the intensity, spatial distribution, and dynamic process of the hammer shock waves. This invention achieves rapid, accurate, and comprehensive characterization of the aerodynamic load of hammer shock waves, providing reliable input loads directly for the strength design of complex structures such as S-curve air intakes, thereby improving aircraft safety.

The invention provides an oil return pipe mechanism and a compressor. The oil return pipe mechanism comprises an oil return pipe, a supporting column, a spring, an activation valve plate and a fixed valve plate, and the oil return pipe is communicated with an upper support oil pool, a lower support oil pool and a bottom oil pool. The activation valve plate can slide and is initially attached to the fixed valve plate under the elastic force of the spring; when the pressure of the oil pool rises to a set value, the oil pushes and activates the valve plate to overcome the resistance of the spring, a corresponding oil return channel is opened, and redundant oil is guided back to the oil pool at the bottom. The upper support oil return pipe is opened preferentially to maintain the pressure of the backpressure oil groove, and the lower support oil return pipe is opened to further relieve pressure when the rotating speed is increased, so that self-adaptive oil pressure adjustment under different working conditions is achieved, dynamic disc backpressure is stabilized, friction loss is reduced, and operation reliability is improved. The scroll compressor is reasonable in structural layout, low in machining precision requirement, high in oil return efficiency and suitable for scroll compressors with various rotating speed frequencies.

The invention relates to a magnesium steam dynamic flow guide baffle, a magnesium ingot reduction device and a manufacturing method. The magnesium steam dynamic flow guide baffle comprises a shell, a base and a dynamic adjusting mechanism. The shell is matched with a tank opening of the magnesium ingot reduction tank in size; the end, close to the crystallization barrel, of the shell is open, and the other end is provided with an air inlet. The base is mounted in the opening, and a movable cavity is reserved between the base and the air inlet; at least one air outlet and at least one mounting cavity are formed in the base; the air outlet penetrates through the base and is used for communicating the movable cavity with the outside. According to the invention, the dynamic adjusting mechanism is arranged; closed-loop regulation of pressure triggering-dynamic pressure relief-automatic reset is formed, sudden pressure rise is effectively avoided, and the pressure in the reduction tank is kept stable, so that the pressure load of the reduction tank is effectively reduced, the service life of equipment is greatly prolonged, meanwhile, magnesium steam can be relatively uniformly distributed, and the service life of the equipment is prolonged. And a large amount of magnesium steam produced in the reduction tank cannot enter the crystallization barrel in a short time, so that the crystallization effect is greatly improved.