413 results about "Maximum pressure" patented technology

The invention provides a method and a system for controlling a stable grasping force threshold value of a vibration manipulator for a camellia oleifera tree and the manipulator, and relates to the field of technical mechanical engineering and automatic control. The stable grasping force threshold value of the vibration manipulator for the camellia oleifera tree is obtained by obtaining a surface friction coefficient of the camellia oleifera tree, determining a damage threshold value, measuring a claw finger opening angle and clamping pressure when the manipulator works, and determining a clamping pressure range; the maximum pressure, the minimum pressure and the equivalent pressure are calculated, the clamping pressure of the mechanical arm is adjusted, the natural frequency and the maximum dynamic displacement response of the mechanical arm claw fingers are obtained, the claw finger opening angle and calculation data are adjusted based on the natural frequency and the maximum dynamic displacement response, and it is ensured that the grabbing force index is smaller than the damage threshold value through iterative adjustment. Mechanical simulation and actual measurement data are comprehensively utilized, through feedback adjustment and fine control, the problems of mechanical arm abrasion and low efficiency caused by excessive pressure and load in the prior art are successfully solved, the service life of the mechanical arm is prolonged, and the production efficiency of the mechanical arm is improved.

The invention relates to an optimal design method for controlling leakage pressure rise of a production pipe column. The method comprises the steps that whether annulus liquid in an oil sleeve annulus of a target gas well leaks or not is determined; if the annulus liquid in the oil sleeve annulus of the target gas well does not leak, the depth of a leakage point of the production pipe column is determined; under the condition that the depth of the leakage point is determined, a first changing curve of the maximum pressure value of the oil sleeve annulus along with the annulus liquid density is determined; according to the pressure bearing capacity of an oil pipe head, a production pipe column, a production casing and a packer, a second changing curve of the maximum value of the pressure control range of the oil sleeve annulus along with the annulus liquid density is determined; and the annulus liquid density is optimized and determined according to the first change curve and the second change curve, so that the oil sleeve annulus pressure is reduced to be within a safety threshold value. The annular pressure of the oil sleeve can be reduced to be within the safety threshold value on the premise that a production pipe column is not replaced and a well is not overhauled, the pipe column leakage pressure rising phenomenon is effectively controlled, the phenomenon that the pressure bearing capacity of a shaft is exceeded is avoided, the control cost is reduced, and the maintenance period is shortened.

The invention discloses an anti-liquid-impact compressor cylinder structure, a compressor and a wellhead natural gas compression method, and relates to the technical field of compressors, the cylinder structure comprises a cylinder barrel and a piston ring assembly, a piston cavity is formed in the cylinder barrel, the cylinder structure further comprises a partition plate, the partition plate divides the piston cavity into a working cavity and a buffering cavity, and the piston ring assembly is arranged in the working cavity; the communication channel is used for realizing mutual communication of the working cavity and the buffer cavity on the two sides of the partition plate; the partition plate is configured in the mode that when the pressure difference between the pressure of the working cavity and the pressure of the buffer cavity exceeds a set threshold value, the fixed relation of the partition plate in the piston cavity is damaged under the pressure difference between the two sides of the partition plate, the partition plate can move towards the side where the buffer cavity is located under the pressure difference, the compressor comprises the cylinder body structure, and the compression method is achieved based on the cylinder body structure. According to the scheme, the maximum pressure in the cylinder is reduced by adopting a method of expanding the clearance volume of the cylinder body when the liquid impact phenomenon occurs, and the response speed in the clearance volume expanding process can be effectively optimized.

The invention discloses a pressure controller for a water supply and drainage system and a regulation and control method, and relates to the technical field of emergency protection devices. The method comprises the following steps: acquiring monitoring data of each pressure controller; based on the monitoring data, the pressure value gradient amount of each pressure controller is obtained; obtaining an abnormal region position of the conveying pipeline based on each pressure value gradient amount; obtaining a first pressure controller based on the abnormal region position; and the first pressure controller is adjusted, so that the maximum pressure value of the abnormal area position is smaller than or equal to a standard pressure threshold value. Through the arrangement of the pressure controller capable of measuring the pressure and position of the conveying pipeline, the position where turbulent flow or vortex occurs in the conveying pipeline can be determined, then the pressure of the abnormal area of the conveying pipeline is adjusted based on the corresponding pressure controller, and the situation that the abnormal area of the conveying pipeline is damaged due to the too large pressure is avoided.

The invention discloses a piezoelectric ceramic stack driven impact press-in test method and a test system thereof. According to the invention, a piezoelectric ceramic stack is used as a drive, a sample is carried on a displacement table, measurement parameters in an impact press-in test are monitored through a force sensor and a displacement sensor, a computer is used for realizing accurate control and subsequent processing and analysis of the measurement parameters, and the whole test adopts electric control actuation; the device is simple in structure and convenient to operate and control, the pressure head can be accurately controlled to be impacted and pressed into the surface of a sample at a certain speed, and the maximum press-in load and the maximum press-in depth in the impact press-in process can be estimated according to the maximum output displacement of the pressure head under the free condition; compared with other impact press-in tests, the impact press-in test method has the advantages that the safety and the stability are well guaranteed, and the impact press-in test method has great application potential.

Devices and methods which dynamically adjust tire pressure using pressure reserves stored and actively maintained within the inflated space of the tire / wheel assembly. In some examples, pressure reserves are stored by pumping gas into tanks and / or expandable envelopes mounted the circumference of the wheel. In some examples, the pumps themselves, and optionally power reserves and / or power generating devices are also positioned within the inflated space of the tire / wheel assembly. Optionally, pressurization is in stages, e.g., from a mid-pressure level in expandable envelopes up to a maximum pressure level in the tanks. Optionally volumes containing stored elevated pressures and / or partially evacuated pressures of gas are dynamically valved in response to operating conditions and events, allowing rapid pressure adjustment.

The utility model provides an open-loop controlled multifunctional hydraulic pulse test bench, which comprises a storage oil tank, an oil supply pump machine, a reversing valve, a pressurizing oil cylinder and an oil supplementing overflow valve, according to the test bed, a large amount of oil flows into a system at the moment that an oil way is opened by a reversing valve, and due to the fact that an overflow valve has a lag phenomenon in response, oil pressure instantaneously generates an overshoot peak value, pressure in a pipeline rapidly rises and a pressure peak appears, then the overflow valve is conducted, the oil is guided out along the overflow valve, and the pressure in the system is reduced to the set pressure of the overflow valve; water hammer waves and rectangular waves of various waveforms and frequency bands can be generated by adjusting the diameter of a variable damping hole of the one-way throttle valve and the rotating speed of the motor, so that the hydraulic pulse test bed can form hydraulic pulse waveforms of various waveforms and frequency bands; the set pressure of the overflow valve is increased, meanwhile, the travel switch loses efficacy, and when the reversing valve is located at the right position all the time, a damage test can be conducted on the hydraulic pipeline to measure the maximum pressure value capable of being borne by a tested piece.

Device (10; 110; 210) for conveying one or more fluids through an outlet line (44), comprising: a housing (20; 120; 220) with a chamber (22; 122; 222) for receiving and / or holding one or more pressurized fluids and an outer surface (24; 124), wherein the housing (20; 120; 220) has a first outlet opening (32; 132; 232), a first inlet opening (30; 230), a second outlet opening (34; 234) and a second inlet opening (36; 236), each opening extending from the chamber (22; 122; 222) to the outer surface (24; 124) to receive conveying means; a first outlet conveying means (42; 142; 242) for connection to an analytical device (65), wherein the first outlet line means (42; 142; 242) is received from the first outlet opening (32; 132; 232) and is in communication with the chamber (22; 122; 222) to guide fluids out of the chamber via the first outlet opening; a first inlet line means (40; 140;240) for connection with a first feed means (70; 170), wherein the first inlet line means (42; 140; 240) is received by the first inlet opening and communicates with the chamber (22; 122; 222) to supply a first fluid into the chamber (22; 122; 222); a second inlet line means (46; 146; 246) for connection with a second feed means (95; 195), wherein the second inlet line means (46; 146; 246) is received by the second inlet opening (36; 136; 236) and communicates with the chamber (22; 122; 222) to supply a second fluid into the chamber; a second outlet line means (44; 144; 244) for connection with a waste container, wherein the second outlet line means (44; 144; 244) is received from the second outlet opening (34; 234) and is in communication with the chamber (22; 122; 222) to guide fluids out of the chamber via the second outlet opening (34; 234);a fitting (241, 243, 245, 247) arranged between each opening (232, 230, 234, 236) and the associated conduit means (242, 240, 246, 244) and comprising a first valve means configured to form an intermediate fluid seal and to retain the conduit means in each opening at a chamber pressure between 15,000 and 120,000 psi; a first outlet conduit valve means (52; 152) arranged in the first outlet conduit means (42; 142; 242) configured to assume a closed position to prevent fluid flow and an open position to allow fluid flow, the valve means being configured to respond to a signal; a first supply means (70; 170) connected to the first inlet conduit means (40; 140;240) connected and configured to assume a supply state to supply the first fluid at a pressure up to a maximum of 120,000 psi and configured to assume a stop state in which the first fluid is not supplied; and a control means (80; 180) for controlling the first outlet line valve means (52; 152) and the first supply means (70; 170), wherein the control means (80; 180) is configured to send a signal (82; 182) to the first outlet line valve means (52; 152) to assume either the open or the closed position, and is configured to send a signal (72; 172) to the first supply means (70; 170) to assume either the supply state or the stop state.;

The invention relates to the field of pressure difference control, in particular to a clean room pressure difference self-adaptive control method, device and equipment and a medium. The method comprises the steps that the current air flowing state of the clean room can be accurately reflected by obtaining the air supply amount data and the air return amount data in real time, and the requirement for pressure change in the clean room can be more accurately reflected according to the maximum pressure difference air amount determined on the basis of the data. By establishing the first air leakage quantity fluctuation function corresponding to the basic pressure difference air quantity fluctuation value, namely by considering the air leakage quantity caused by the sealing condition of the clean room, tiny pressure fluctuation possibly existing in the clean room can be considered and adapted, and therefore the precision of pressure difference control of the clean room is improved.

The invention relates to a method for monitoring and managing the working state of an oil pressure press, and belongs to the technical field of oil pressure press management.The method comprises the steps that a knowledge graph is constructed according to pressure performance characteristic data under all working parameters, and the real-time working parameters of each oil pressure press are obtained; and finally, according to the knowledge graph and the real-time working parameters of each oil pressure press, the real-time pressure performance of the oil pressure press is obtained, and the current pressure minimum demand data information is obtained. And intelligent management is conducted on the oil pressure presses according to the real-time pressure performance of the oil pressure presses, the current pressure minimum demand data information and the maximum pressure performance characteristic data of each oil pressure press within the preset time. According to the method, the pressure performance of the oil pressure press is evaluated, so that the working parameters of the oil pressure press are adjusted according to the evaluation result, the working requirements are met, and normal operation of the oil pressure press is guaranteed.

The invention relates to the technical field of ship mooring systems, and discloses a self-energy-storage device and method applied to mooring constant tension. A piston pull rod of the hydraulic cylinder is connected with one end of the cable; an energy storage module; the energy storage module comprises a first energy accumulator and a second energy accumulator, the volume of the second energy accumulator is larger than that of the first energy accumulator, and the maximum pressure intensity of the first energy accumulator is set to be larger than that of the second energy accumulator; the first energy accumulator and the second energy accumulator are connected with an oil cavity of the hydraulic cylinder through hydraulic pipelines respectively. The first energy accumulator and the second energy accumulator are connected through a hydraulic pipeline. The pressure in the hydraulic cylinder is adjusted by adjusting the hydraulic oil amount in the hydraulic cylinder through the first energy accumulator and the second energy accumulator, so that the tension in the mooring rope is constant within a preset value during working. By storing self-generated energy of ship movement, the problems that extra energy consumption is needed for providing constant tension for ship mooring, and cable tension and elongation are insufficient are solved.

The invention relates to the technical field of shield tunneling machine construction, in particular to a shield tunneling machine settlement control method which comprises the steps that the maximum pressure and the minimum pressure of a shield tunneling machine in an undercrossing subway tunnel section are calculated according to the burial depth and geological data, and when the shield tunneling machine conducts tunneling, the notch pressure of an excavation face is monitored according to the maximum pressure and the minimum pressure; in the tunneling process of the underpass subway tunnel section, the tunneling speed and the unearthing amount of a shield tunneling machine are monitored, meanwhile, grouting is conducted through radial holes in a shield shell by adopting a plastic material, and a gap, caused by excavation, between a soil body and the shield shell is filled; and when the shield tunneling machine tunnels to the granite layer, slurry injection parameters are controlled. According to the scheme, the safety and reliability of the construction process can be effectively controlled, the construction settlement condition is effectively controlled, it is guaranteed that the safety of the subway tunnel and the surrounding ground is effectively guaranteed, and related potential safety hazards are eliminated.

The invention belongs to the field of natural gas well exploitation control, and discloses a gas well wellhead pressure drop control method and system, electronic equipment and a medium. Judging whether the wellhead pressure is greater than a pressure threshold, and if so, calculating the wellhead pressure drop of the gas well in the current comparison period; judging whether the wellhead pressure drop is greater than the maximum pressure drop threshold value, if so, controlling the valve opening to be reduced, and then obtaining the wellhead pressure of the gas well in the preset comparison period again, if not, judging whether the wellhead pressure drop is less than the minimum pressure drop threshold value, if so, controlling the valve opening to be increased, and then obtaining the wellhead pressure of the gas well again, and if not, controlling the valve opening to be reduced. And re-acquiring the wellhead pressure of the gas well. According to the method, the pressure drop of the wellhead is controlled within a stable range, accurate control over the gas well is achieved, the effects of delaying fracture closing, reducing the formation sand production amount and the like can be achieved, stable exploitation of the gas well is guaranteed, and meanwhile the EUR of the gas well is improved.

The utility model belongs to the technical field of aluminum alloy templates, particularly relates to an aluminum alloy template with a double-layer structure, and aims to solve the problems that the pressure of a large amount of pouring cement on the aluminum alloy template is increased along with the increase of the height of a poured wall body, and particularly, the aluminum alloy template at the bottom bears the maximum pressure and is easy to damage and deform. According to the technical scheme, the formwork comprises a formwork body, a plurality of installation holes matched with bolts for installation and use are formed in the periphery of the formwork body, the installation holes are arranged at equal intervals, and aluminum plates matched with the formwork body in size are arranged in the formwork body. Two cross rods are symmetrically welded to the two ends of the inner wall of the formwork body, and the cross rods are hollow. According to the utility model, the structural stability of the template main body is integrally improved, the anti-pressure capability is improved, the impact force of a large amount of poured cement on the template main body is dealt with, the durability is improved, the recycling is facilitated, and the construction cost is reduced.

The invention discloses a marine high-pressure common rail diesel engine MPC combustion control method based on a physical informatization neural network, and belongs to the field of marine high-pressure common rail diesel engine control. The problems that physical consistency of a model and a real machine is ignored and the generalization ability of the model is poor due to the fact that only data driving is relied on are solved. The method comprises the following steps: keeping a combustion midpoint unchanged, and acquiring in-cylinder pressures, in-cylinder maximum pressure rise rates, indication heat efficiency and emission data of different pilot injection fuel ratios and pilot main injection positive time intervals; calculating the average indicated pressure circulation change of the diesel engine, screening data and calculating the accumulated heat release amount and the combustion midpoint; obtaining an influence rule of related characterization parameters of combustion in a diesel engine cylinder, and determining a crank angle corresponding to pilot injection timing, a pilot injection fuel ratio, a pilot main injection interval boundary and an upper limit of a maximum pressure rise rate of cylinder pressure; a diesel engine in-cylinder combustion prediction output model and an MPC controller are constructed; and updating control parameters and combustion state data to realize closed-loop control. The method is used in energy-saving and emission-reducing fields.

The present application relates to an air-jet type spinning device provided with a spinning starter system, in which the included spinning starter system is arranged to:-pneumatically supply an injector or venturi nozzle (36) at an initial maximum pressure pmax in order to retrieve fibres in a fibre introducer (20),-supply fibres into a spinning chamber (16) and then into a spindle (24) of the spinning chamber (16); the spinning chamber (16) is pneumatically supplied with a main nozzle (40) such that the two compressed air jets overlap each other, and the ejector or venturi nozzle (36) is gradually closed according to an average pressure gradient having an absolute value of less than 6 bar / sec. The utility model has the main advantage of improving and adjusting the starting of the air jet spinning process, which is particularly useful for yarns made of hard fibers and for reducing the fiber passing time in the spinning chamber.

The invention relates to the technical field of centrifugal pumps, and particularly discloses a high-leakproofness non-variable-capacity pump and a component thereof, the high-leakproofness non-variable-capacity pump comprises a pump shell and an impeller, the pump shell is provided with a water inlet and a water outlet, the pump shell is in a volute shape, the volute shape comprises a wide section and a narrow section, and the high-leakproofness non-variable-capacity pump further comprises a flow aiding mechanism; the flow dividing device comprises a flow dividing opening and a flow dividing sleeve which are formed in the narrow section of the pump shell, a plurality of liquid inlet holes are formed in the water inlet in a circumferential array mode, and the flow dividing opening and the liquid inlet holes are covered with the two ends of the flow dividing sleeve respectively. According to the centrifugal pump, in the operation process of the impeller, fluid is guided to enter the flow dividing sleeve along the flow dividing opening at the volute-shaped narrow section with the maximum pressure through the flow dividing sleeve, then the flow dividing sleeve supplements the fluid to the water inlet of the pump shell, the negative pressure at the water inlet is supplemented, the cavitation condition is relieved, and the service life of the whole centrifugal pump is prolonged.

The invention discloses a testing device and a testing method for an aircraft main wheel turning system. The aircraft main wheel turning system comprises a turning system crank, a turning actuation system, a turning system connecting rod and a turning shaft and is mounted on the test device, and one end of the turning system crank is fixedly connected with a bracket connecting piece of the turning system bracket; the upper end of the turning actuation system is hinged with the other end of the turning system crank; a connecting rod connecting piece at the upper end of a turning system connecting rod is hinged to the third end of a turning system crank, loading points are additionally arranged on the two sides away from the rotation center of a turning shaft, clockwise rotation loading and anticlockwise rotation loading of a main wheel turning system are achieved by switching the loading points, and the loading mode of a conventional loading test bed is expanded. The maximum pressure and the tension locking force of the aircraft main wheel turning system and the turning rate of the aircraft main wheel turning system can be tested, the test requirements of the aircraft main wheel turning system are met, and safe, reliable and efficient work of the aircraft main wheel turning system is guaranteed.

The application discloses a centrifugal air compressor surge control method, system, electronic equipment and storage medium, and the centrifugal air compressor surge control method comprises the following steps: obtaining the exhaust pressure variation intensity of a centrifugal air compressor; performing classified control according to the obtained exhaust pressure variation intensity value; when it is detected that the exhaust pressure variation intensity is less than a set maximum pressure variation threshold value and greater than a set minimum pressure variation threshold value, switching the anti-surge valve to an anti-surge automatic control mode; under the anti-surge automatic control, slowly opening the anti-surge valve to introduce airflow into the atmosphere and discharge the airflow; after continuously detecting that the exhaust pressure variation intensity is less than the set minimum pressure variation threshold value and maintaining the set time, switching the anti-surge valve out of the anti-surge automatic control mode and restoring the anti-surge valve to a normal control mode; and when it is detected that the exhaust pressure variation intensity is greater than the set maximum pressure variation threshold value, switching the anti-surge valve to a surge protection mode and switching to a surge fast-opening mode. The application can improve the stability of the centrifugal air compressor.

The invention relates to a method for controlling a hydraulic system (1) for a vehicle having an electrically operated pump (2) that adjusts a system pressure, wherein, for actuating a clutch, the system pressure is controlled between a maximum pressure (p(max)) and a minimum pressure (p(min)) by means of a slave cylinder (6). In order to enable both precise and robust control of the hydraulic system (1), a pressure signal of the system pressure is filtered using different types of filters as a function of at least one operating parameter of the hydraulic system (1).

The invention relates to a powder needleless injection pressure monitoring device, which belongs to the technical field of medical instruments and comprises a pressure sensing needleless injector main body, a partition pressure reading recording display screen, a main body pressure sensor and a pressure sensing medicine tube. The powder needleless injection pressure monitoring device is provided with a medicine tube pressure intensity monitoring structure, an injector injection generation pressure sensing structure and a pressure value display structure at the same time; the pressure sensors arranged at the top of the injection push rod and the upper end of the injection piston push piece are used for accurately sensing the injection generation pressure intensity and the actual acting pressure intensity value, the real-time pressure during needleless injection is sensed and displayed, the actual pressure value of powder needleless injection can be accurately monitored, effective injection is guaranteed, and the injection efficiency is improved. The action pressure intensity verification sensor is used for sensing the actual action and the maximum pressure intensity value of the medicine powder, and the maximum pressure intensity value is compared with a numerical value detected through sensing, so that the monitoring accuracy is further guaranteed, and accurate and effective pressure-controlled injection is completed.

The invention discloses a shield tunneling machine shield tail sealing pressure monitoring method and device, and the method comprises the steps: receiving pressure data collected by a plurality of pressure sensors disposed in a shield tail sealing cavity, and obtaining the maximum pressure data and the minimum pressure data from the pressure data; the pressure sensors are anticlockwise distributed in the annular shield tail sealing cavity at equal intervals; according to the maximum pressure data and the minimum pressure data, performing normalization processing on each piece of pressure data, mapping the normalized pressure data into a preset standardization interval, and matching the pressure data with a corresponding pressure standard value; mapping the pressure standard value to a preset RGB color gradation interval, matching an RGB value corresponding to the pressure standard value, and generating a pressure cloud picture according to the RGB value; and monitoring pressure data in the shield tail sealing cavity according to the pressure cloud picture. According to the invention, the monitoring precision of the shield tail sealing pressure can be improved, and comprehensive and accurate monitoring is provided for the shield tail sealing state.

The invention discloses a surface micro-texture of a radial sealing fin of a cycloid rotor engine. The surface micro-texture comprises a double-layer herringbone groove, a sealing weir area and a sealing dam area. The double-layer herringbone groove is formed in the contact surface of the rotor, gas enters the groove from the upper-layer gas inlet and the lower-layer gas inlet in the vertex angle of the herringbone groove, the maximum pressure value is achieved in the groove, and the gas is exhausted from the upper-layer gas outlet and the lower-layer gas outlet after the pressure difference effect is completed. A plurality of pairs of herringbone grooves are evenly distributed in the radial sealing piece, a sealing weir area is arranged between every two adjacent pairs of herringbone grooves in the axial direction, and a sealing dam area is arranged on the outer side. The herringbone grooves are of an axial symmetry structure, the groove depth is 1-5 micrometers, the number of the herringbone grooves is 2-10 pairs, and the edges can be straight lines, arc lines, spiral lines or sawtooth lines. Gas enables the radial sealing fins and the rotor to be tightly adsorbed through pressure difference, and the sealing weir area and the sealing dam area provide multi-layer sealing protection. The air tightness problem of the radial sealing piece is solved, the stable radial sealing performance of the cycloid rotor engine is achieved, and gas leakage is remarkably reduced.

The invention discloses a Smart Crown cold-rolling mill intermediate roll shape and a design method thereof, and belongs to the technical field of cold-rolled sheet strip steel production. According to the method, values of a, b, c and phi are randomly selected within a parameter range according to setting of boundary conditions, optimal values of a, b, c and phi are calculated according to the maximum roll gap adjustment value and the minimum inter-roll pressure difference of an objective function, and therefore the optimal roll type of the intermediate roll of the Smart Crown cold rolling mill is obtained. According to the method, an optimization algorithm is combined with a load roll gap shape calculation model, elastic deformation of the roll in a load state is fully considered, the method is more suitable for actual production, and the purpose of improving the strip steel plate shape quality can be achieved.

The embodiment of the invention discloses a fuel gas safety Rubik's cube and a monitoring method thereof. The Rubik's cube comprises an electromagnetic valve used for controlling opening / closing of a fuel gas pipeline, a pressure sensor used for detecting the pressure of the fuel gas pipeline and a temperature sensor used for detecting the environment temperature. When the fuel gas safety magic cube detects that the real-time pressure value P of the fuel gas pipeline exceeds the maximum pressure preset value PMAX or is smaller than the minimum pressure preset value PMIN through the pressure sensor, the electromagnetic valve is closed. According to the self-closing valve, abnormity detection is more accurate, and the abnormity can be directly improved to be within 5% compared with an existing self-closing valve 25%; the state can be updated in real time, and a user is clear at a glance; according to the invention, the security check of the gas company can be remote, and the operation cost is greatly reduced.

The invention provides a hydraulic system and engineering machinery. The hydraulic system comprises a hydraulic pump, a proportional directional valve, a compensation valve and a first overflow valve. An oil outlet of the compensation valve is communicated with an oil inlet of the proportional reversing valve, and an oil inlet of the compensation valve is communicated with an oil outlet of the hydraulic pump; an oil inlet of the first overflow valve can selectively communicate with a first oil port of the proportional reversing valve or a second oil port of the proportional reversing valve, a first cavity of the compensation valve and the oil inlet of the first overflow valve are connected with the same oil port of the proportional reversing valve, and an oil inlet of the proportional reversing valve can communicate with a second cavity of the compensation valve. The first chamber and the second chamber are located on a rearward side of the compensation valve. As the compensation valve can control the front and back pressure difference of the proportional reversing valve to be basically constant, the output flow is not influenced by the load. The overflow valve limits the maximum pressure of an oil way, and the minimum overflow energy consumption is achieved.

The present invention relates to the technical field of cementing equipment, and is an integrated isolation type drilling-free cementing tool, comprising a housing, a sleeve, a rubber cylinder, a positioning mechanism, shear pins, and a vertically arranged center tube. The present invention has a reasonable and compact structure, and the center tube is lowered into a predetermined position in the well together with the casing string. After the first-level cementing collision pressure is completed, the casing continues to be pressurized. When the spacer moves downward to the set position, the positioning mechanism fixes the spacer and the housing together. At this time, the rubber cylinder expands outward, and the expanded outer diameter reaches the maximum value. When the pressure reaches the maximum pressure-bearing value of the bursting disc, the bursting disc ruptures, and the inside of the casing and the annulus form a circulation channel to perform the second-level cementing. The present invention can realize the expansion sealing of the rubber cylinder only through a sleeve, and the positioning mechanism can form a positioning effect on the sleeve, and the sleeve cannot move up and down. The inside and outside of the integrated isolation type drilling-free cementing tool are still two independent working systems, which will not be connected in series, greatly improving the success rate of the tool.

The utility model discloses a positioning structure of explosion-proof spherical shell machining welding equipment, and belongs to the technical field of positioning auxiliary mechanisms of explosion-proof spherical shell machining equipment. The device comprises a welding workbench, and a gear is movably connected in the welding workbench. The explosion-proof spherical shell is placed between the two cylinders, the cylinders on the two sides are driven to get close to each other through rotation of the motor, the cylinders drive the movable rods to get close to each other, the movable rods are arranged in the cylinders, when the explosion-proof spherical shell makes contact with the small ball, the movable rods are squeezed, then the compressed springs are compressed, and under the action of the limiting rings, the small ball can be driven to rotate. When the movable rod moves to the maximum compression position, the movable rod does not continue to move any more, at the moment, the movable rod can rigidly clamp the anti-explosion spherical shell, the movable rods at different positions can surround the two sides of the anti-explosion spherical shell due to the fact that the contact positions of the movable rods and the anti-explosion spherical shell are different, and therefore the positioning stability of the anti-explosion spherical shell is improved, and the service life of the anti-explosion spherical shell is prolonged. The positioning device has the advantage of being good in positioning effect.

A trailer system with a trailer and a booster is provided. The trailer can have a hitch assembly provided at a front end of the trailer, a load bed provided behind the hitch assembly, and an axle assembly. The booster can have a connection assembly pivotally connecting the booster to a rear end of the trailer and an axle assembly. The connection assembly can include a booster hydraulic cylinder to dampen the pivoting of the booster; and an axle assembly comprising: a booster suspension frame; at least one axle; ground wheels provided on each axle; a booster suspension having at least one booster suspension air spring controlling the height of the booster suspension frame relative to the ground wheels; and a pressure regulator limiting the maximum pressure of a fluid supplied to the at least one booster suspension air spring.

The invention relates to a method for controlling a hydraulic system (1) for a motor vehicle with an electrically operated pump (2) that regulates the system pressure, wherein the system pressure is controlled between a maximum pressure and an opening pressure to actuate a clutch (17) by means of a slave cylinder (6). To prevent damage to the hydraulic system (1) due to excessive system pressure, pressure values ​​of a pressure signal of the system pressure are statistically evaluated after exceeding the maximum pressure over a predetermined measurement interval, and an error is output if a predetermined probability of the pressure values ​​exceeding the maximum pressure is reached.