683results about How to "Small pressure fluctuations" patented technology

The invention discloses a method for recovering potential energy of a movable arm of a hydraulic digging machine and a device thereof. The method comprises the following steps: firstly, the potential energy is stored through an energy accumulator in the retraction process of a hydraulic cylinder; and secondly the stored energy in the energy accumulator drives a generator to generate electricity, thereby realizing the recovery of the potential energy of the movable arm of the hydraulic digging machine. A mode for storing the potential energy is to convert the potential energy into pressure energy. The energy accumulator and the generator are connected through a proportioning valve so as to control the rotational speed of the generator. The method realizes high-efficiency recovery of the potential energy of the movable arm of the hydraulic digging machine; the principle of the method is to skillfully change the working time of hydraulic oil for power generation through the function of energy storage of the energy accumulator and provide effective buffering for recovering the potential energy; in addition, through the throttling control of the proportioning valve, the method reduces pressure fluctuation of the hydraulic oil in the power generation process, realizes the adjustment of the working rotational speed of the generator, improves the working efficiency of the generator and further improves the efficiency of energy recovery.

The present invention provides a method of making a fluoropolymer comprising repeating units derived from one or more gaseous fluorinated monomers. The method comprises an aqueous emulsion polymerization of gaseous fluorinated monomers in the presence of an ether selected from the group consisting of dimethyl ether (DME), methyl tertiary butyl ether (MTBE) and mixtures thereof.

The invention discloses a system for differential recovery of potential energy of a boom of an oil liquid hybrid power excavating machine. The system comprises a variable capacity pump, a multi-channel valve, a boom cylinder, an operating handle, a controller, a hydraulic control reversing valve, a hydraulic control reversing and throttling valve, a hydraulic control unloading valve, an energy accumulator, an electro-hydraulic proportional valve and a one-way valve. The controller is used for controlling the electro-hydraulic proportional valve and the variable capacity pump according to pressure at an outlet of the variable capacity pump and a pressure signal of the energy accumulator, thereby solving the flow distribution problem of the energy accumulator and the variable capacity pump. The energy accumulator is an energy storage element which can transform descending kinetic energy and potential energy of the boom to hydraulic energy and reasonably distribute the energy for a main power source and an auxiliary power source, and a working device is driven by the pump-energy accumulator. The system can avoid the waste of a large amount of the descending kinetic energy of the boom, reduce the energy transformation link, enable an engine to stably work in a high-efficient fuel oil region, improve the fuel coil economy of the excavating machine and reduce the emission of the system.

The invention relates to a two-position three-way inverse proportion decompression electromagnetic valve for an AT (Automatic Transmission). The two-position three-way inverse proportion decompression electromagnetic valve is mainly formed by a main valve and a proportion electromagnet, wherein the main valve is formed by a valve body, a valve core which is positioned at the inner part of the valve body, a valve seat which is sleeved on the valve body and an inner valve core which is positioned at the inner part of the valve core and close to one side of the valve seat, and the proportion electromagnet is formed by a sliding bearing, a bearing seat, a pole shoe, an armature, a top rod, a stroke gasket, a stop iron, a spring seat, a regulating spring, a baffle plate, a regulating screw, a baffle plate cushion, a coil and a yoke iron. According to the two-position three-way inverse proportion decompression electromagnetic valve disclosed by the invention, the problems such as lower response speed, larger pressure fluctuation, short service life, large leakage rate and high manufacturing cost of an existing inverse proportion decompression electromagnetic valve for the AT are solved, and the two-position three-way inverse proportion decompression electromagnetic valve disclosed by the invention has the advantages of high response speed, small pressure fluctuation, long service life , small leakage rate, lower manufacturing cost and the like.

The invention discloses a servo brake cylinder used for a distributed composite brake system, the distributed composite brake system adopting the servo brake cylinder and a brake method of the distributed composite brake system adopting the servo brake cylinder. The servo brake cylinder comprises a shell body, an electromotor, a coupler, a ball screw assembly composed of a nut and a lead screw, abearing, a retainer ring, a piston, a cylinder body and a return spring, wherein an inner hole is formed in the center of the piston, the inner hole comprises a tapered first conical surface, a cylindrical surface and a gradually-expanded second conical surface, the left end of the lead screw extends in the axial direction to sequentially form a tapered third conical surface, a cylindrical surfaceand a gradually-expanded fourth conical surface, the first conical surface cooperates with the fourth conical surface to form an output valve, and the second conical surface cooperates with the thirdconical surface cooperate to form an input valve. According to the servo brake cylinder used for the distributed composite brake system, the distributed composite brake system adopting the servo brake cylinder and the brake method of the distributed composite brake system adopting the servo brake cylinder, the advantages of being compact in structure, flexible in control, high in braking response, high in braking pressure control precision, reliable in failure protection capability, low in manufacturing cost and the like are achieved, so that an intelligent driving automobile is good in motion stability and high in reliability during braking.

The invention discloses an electro-hydraulic combined braking system with the electric power function and applicable to a regenerative braking automobile. A braking pedal pushes a piston ejector rod of a braking master cylinder to move through a pedal push rod, and an electric braking power device assists in pushing the ejector rod of the braking master cylinder to move. The structure of combining a ball screw pair with a reacting disc is adopted for the electric braking power device, and therefore the torque output by rotation of a motor can be converted into linear movement of an output rod. In the braking process, the movement of the piston ejector rod of the braking master cylinder can be braked by controlling rotation of the motor. According to received collection signals of all sensors on the automobile, an electronic control unit controls a hydraulic control system and the electric braking power device and selects one braking mode, and the braking modes include the electric power mode, the regenerative braking mode, and the driving braking mode. The electro-hydraulic combined braking system has the advantages of having the electric braking power and driving braking functions, and being high in reliability, low in manufacturing cost, small in pressure fluctuation and high in pressure adjusting accuracy.

The invention relates to a rotary sealing feeding valve which comprises a valve casing, side flanges which are symmetrically arranged and a star-shaped rotor, wherein the side flanges are fixedly installed at the front side and the back side of the valve casing; a main shaft is supported between the side flanges; and the star-shaped rotor is supported between two side flanges in the valve casing. The invention is characterized in that the space between each side flange and the valve casing is divided into a plurality of sealed chambers by the star-shaped rotor; a pressure-reducing balanced opening and a pressure-increasing balanced opening are arranged on the valve casing; and the valve casing also comprises a feeding opening and a discharge opening. The rotary sealing feeding valve is a rotary valve which is suitable for continuous feeding in the environment with pressure difference and temperature difference.

The invention discloses a hydraulic driving system for an offshore drilling compensation winch.A hydraulic secondary regulation element and a driven hydraulic cylinder jointly drive the winch to fulfill a heave compensation function, and a bit feeding hydraulic motor drives the winch to fulfill an automatic bit feeding function.During compensation, the driven hydraulic cylinder and a liquid-gas energy storage device thereof are used or bearing all static loads of a drilling rig and periodically recovering and releasing gravitational potential energy of loads; the hydraulic secondary regulation element operates in a constant-pressure network to overcome other loads in the compensation process, and the liquid-gas energy storage device periodically recovers and releases inertia kinetic energy of the a winch rotary system.During bit feeding, the driven hydraulic cylinder and the liquid-gas energy storage device thereof recover the gravitational potential energy of the loads of the drilling rig and release in lifting of a drilling rig traveling system.The hydraulic driving system is integrally compact in structure, a hydraulic energy recovery system is high in operation efficiency and long in service life, and an engine is low in power and power consumption.

The invention belongs to the technical field of oil drilling, and relates to a double-throttle control slurry pump distributing manifold for applying wellhead back pressure and a method. The double-throttle control slurry pump distributing manifold for applying the wellhead back pressure comprises a main pipe, a manifold four-way joint, a first distributing pipeline, a second distributing pipeline and a third distributing pipeline; the manifold four-way joint is respectively connected with the main pipe, the first distributing pipeline, the second distributing pipeline and the third distributing pipeline; a pressure gauge is installed on the main pipe; and the first distributing pipeline is provided with a first stop valve and a first throttling valve, the second distributing pipeline is provided with a second stop valve and a second throttling valve, and the third distributing pipe is provided with a third stop valve. The pump is unnecessary to stop and start in the connecting process, the pulling out process and the drilling down process, so that the pressure fluctuation on the bottom of a well can be reduced, and the control capacity for the bottom pressure can be improved; a back pressure pump is not needed, so that additional work caused by the back pressure pump is avoided, the nonproduction time can be reduced, and the drilling cost can be reduced; the pollution caused by the leakage of the back pressure pump can be avoided; and the energy and the floor area can be saved.

The invention discloses a hydraulic control device for a hybrid power transmission, wherein a main oil-way is respectively connected with a lubricating oil-way, a clutch control oil-way and an electromagnetic valve control oil-way, the main oil-way is connected with a cooling and lubricating oil-way through an unloading valve, the cooling and lubrication oil-way is connected with a valve core control oil port of the unloading valve at the same time, the oil outlet of the unloading valve is respectively connected with an oil inlet of an overflow valve and the clutch control oil-way, the oil outlet of the overflow valve is connected with the lubricating oil-way, the clutch control oil-way is respectively connected with oil inlets of proportional reducing valves A and B, a reducing valve is arranged between the electromagnetic valve control oil-way and the main oil-way, the electromagnetic valve control oil-way is respectively connected with valve core control oil ports of the proportional reducing valves A and B through oil-saving holes, and is respectively connected with a switching electromagnetic valve and a halt locking hydraulic cylinder through the oil-saving holes. The hydraulic control device has simple structure, can rapidly lubricate the transmission, and is suitable for the hydraulic control of the hybrid power transmission.

The invention relates to the liquid rocket propulsion technology, and particularly discloses a thrust chamber collector with a flow uniformizing function. A body shell is composed of an inner wall and an outer wall together. A cylinder formed when the inner wall is closed serves as a combustion chamber. An interlayer between the inner wall and the outer wall forms a cooling passageway. Annular grooves are formed in the inlet and the outlet of the cooling passageway. A bent pipe of the collector is welded and connected to the body shell at the annular groove in the inlet of the cooling passageway. A collector cavity is formed by the bent pipe and the body shell. The opening of the collector cavity is welded and connected to an inlet flange to form a collector inlet. Due to the double-collection-cavity structure, fluid is secondarily uniformized before entering the cooling passageway; by means of a horn-shaped expansion inlet with a reverse-Y-shaped diversion piece, fluid can more stably turn at the collector inlet, pressure fluctuation at the inlet and the two sides is reduced, local pressure loss can be reduced, and the diversion piece can play a role in reinforcing structure supporting.

The invention discloses an energy-saving control method for a compressed air industrial screw-type air compressor group control system. The method comprises automatic control of the number of air compressors and automatic loading and uploading control of screw-type air compressors. In the system, gray scale prediction of total run traffic is conducted to control start and stop of the air compressors, so that the frequent start and stop defect of the air compressors is overcome, and the system operation stability is greatly improved; meanwhile, automatic loading and uploading control of the screw-type air compressors is carried out, so that the system operating pressure is stable, the pressure fluctuation range is reduced, and a defect that the power consumption of a frequency converter is increased caused by modification of frequency conversion control of an air compressor group. The method has the characteristics that the energy utilization efficiency is high, and the system is flexible in operation and stable in running.

The invention discloses a braking system with combined function of drive-by-wire and power-assisted and with a manpower-magnification action. Functions such as electric braking power-assisting, active braking and regenerative braking can be achieved, control can be conducted on a motor, a hydraulic control unit and several magnetic valves according to the collected signal of a brake pedal displacement sensor and a master cylinder pressure sensor through an electronic control unit, and choice on each braking mode is realized. When the system works under the drive-by-wire mode, the motor is controlled by the brake pedal displacement sensor to push the master cylinder piston to output the brake pressure to a wheel cylinder, and a brake pedal and a friction brake are coupled completely at the moment; when the system works under the electric power-assisting mode, the pedal effort is input into a master cylinder back cavity after being amplified through a human-powered cylinder, a first piston of the master cylinder is pushed, at the same time, the motor output torque is controlled by the electronic control unit, the electronic control unit exerts assisting power on the first piston of the master cylinder, and the brake pressure is output to the wheel cylinder; when the system works under the active braking mode, the electronic control unit controls the motor output torque to make the main cylinder to output the brake pressure to the wheel cylinder.

A medium and high pressure pump systems supplies a cryogenic fluid from a storage tank. The system comprises a pump that is operable to pump cryogenic liquid or a mixture of cryogenic liquid and vapor. The pump preferably comprises an inducer with at least two chambers and means for recycling excess fluid within the inducer instead of returning excess fluid to the storage tank. The reciprocating pump is preferably double acting such that fluid is discharged from the pump during both extension and retraction strokes.

The invention relates to the field of medical instruments and particularly discloses a mechanical ventilation control method of a positive pressure respirator and the respirator. According to the mechanical ventilation control method of the positive pressure respirator, the respiration state is judged by a microcontroller according to air pressure and air flow, the pressure information is used as the input parameter of a PID controller, a control voltage is obtained after the pressure information is input into the PID controller, then an air supply device is controlled, and pressure is provided for a respiration catheter; a next inspiration time is predicted during the expiratory phase, the respirator is controlled to release pressure in advance during the inspiratory phase, and the respirator is controlled to generate positive pressure support at the tail stage of expiration. The mechanical ventilation control method of the positive pressure respirator and the respirator have the advantages that predetermined respiration pressure can be obtained fast, and pressure fluctuation is reduced; due to the fact that the pressure is released in advance before the inspiratory phase, man-machine synchronism is improved; in addition, due to the fact that the positive pressure support is added at the tail stage of expiration, the respirator can better conform with human body respiration physiological characteristics, and the problem that an air passage is closed again due to over low pressure support is solved.

The melt rotating fast filter for extruder consists of mold body, filtering net plate and hydraulic assembly. The split mold body includes material feeding mold body and discharge mold body connected with screws; the ratchet wheel type filtering net plate is fixed with one rotating shaft between the material feeding mold body and the discharge mold body and has several filtering net holes with filtering net inside; the hydraulic assembly connected onto the fixing seat of the oil cylinder includes two parts of a hydraulic cylinder and a draw hook; and the draw hook set on the piston rod has roller unit clamped to ratchet of the filtering net plate. The present invention can realize non-stop fast net replacement, and has great filtering area and clear melt passage maintained during net replacement, small resistance change of the filtering net and less melt pressure fluctuation in the system.

The invention discloses a gas steam combined cycle unit multivariable constrained prediction function load control method. The method is characterized by comprising the steps that (1) an original load instruction counter circuit is adjusted, and a primary frequency modulation instruction is superposed onto a load instruction of a gas turbine; (2) a 2*2 controlled object model with gas turbine fuel valve opening and steam turbine inlet adjusting valve opening as input and combined cycle unit actual power and steam turbine main steam pressure as output is built, wherein the controlled object model is expressed by an equation shown in the specification, PW is the combined cycle unit actual power (MW), TP is the steam turbine main steam pressure (MPa), U1 is the gas turbine fuel valve opening (%), U2 is the steam turbine inlet adjusting valve opening (%), G11 is a transfer function with the U1 as input and the TP as output, G12 is a transfer function with the U2 as input and the PW as output, G21 is a transfer function with the U1 as input and the TP as output, and G22 is a transfer function with the U2 as input and the TP as output; in addition, it is ensured that denominators of the G11 and the G12 are the same, and the denominators of the G21 and the G22 are the same after reduction of fractions to a common denominator is carried out on the transfer functions.

The invention discloses an intermittent hot water circulation pressure stabilization insulation tyre vulcanization technology, comprising the following steps: injecting saturated superheated steam to a vulcanizing machine after spotting, injecting primary superheated water without backing, providing internal pressure rapidly to enable a tread rubber material to fill patterns, injecting secondary superheated water and circulating as external pressure steam is entered to heat a green tyre, starting positive vulcanization, stopping the circulation of the secondary superheated water, feeding external pressure steam continuously, carrying out positive vulcanization for a tyre continuously, cycling the secondary superheated water again, feeding external pressure steam continuously, stopping the circulation of the secondary superheated water, keeping the pressure until the vulcanization is finished, stopping the external pressure steam, discharging the external pressure to atmospheric pressure, discharging hot water in capsules and vacuumizing, completing the vulcanization finally and taking the tire out of a mould. The overcure phenomena of carcass and the belt layer are effectively prevented according to the invention. The durability of the tire is enhanced from original 90 hr to over 110 hr. The service life of the tire is prolonged.

The invention relates to the field of intelligent water supply management systems, and discloses an energy-saving peak-shifting intelligent water supply system based on a cloud technology. The energy-saving peak-shifting intelligent water supply system is characterized by comprising pump houses, water storage tanks, water pump units, water supply pipeline assemblies, data acquisition and transmission units, pump house monitoring units, intelligent water tank adjusting and controlling units, hydraulic data monitoring units, water quality monitoring and treatment units, pipe network hydraulic data monitoring units, a cloud platform server and a cloud platform big data analysis module. The energy-saving peak-shifting intelligent water supply system has the beneficial effects that at the moment which is not water use busy hours, the water storage tanks are subjected to regulation and storage as a whole, pipe network water supply resources are optimized and distributed, the instant water demand on a municipal water supply pipe network during the water use busy hours is reduced, the fluctuation range of the pressure of the water supply pipe network is narrowed, fluctuation of the pressure of the water supply pipe network is low, the phenomenon of leakage of the pipe network can be reduced, stable water supply of a water plant system is guaranteed, the rebuilding requirements of the water factory municipal water supply pipe network and the water supply pipe assemblies are lowered, and national water supply resources and ancillary facilities are saved.

The invention relates to a novel vortex-preventing cone for water feeding of a water pump, belonging to the technical field of hydraulic engineering. The vortex-preventing cone is arranged under a suction flared pipe nozzle of the water pump, the tip of the vortex-preventing cone is just opposite to the center of the suction flared pipe nozzle of the water pump, vortex-preventing teeth are arranged on the conical surface of the vortex-preventing cone, and the plane area of the vortex-preventing cone is more than the area of the suction flared pipe nozzle of the water pump. The uneven vortex-preventing teeth are arranged on the conical surface of the vortex-preventing cone, and the section shape of a rack of the vortex-preventing teeth is rectangular or triangular or trapezoidal. A cone axial line of a flat cone and a pipe core line of a suction flared pipe of the water pump are arranged on the same straight line. The invention has the advantages of simple and scientific structure and reasonable design; the primary basis of a vortex strip is destroyed from the starting point of the vortex strip, circular quantity of water flow in a water inlet region can not accumulate, and the condition of generating high-intensity vortexes is deprived, the water flow in the water inlet region is smooth, the pressure fluctuation is reduced, and the pump vibration is avoided. The invention is suitable for inlets of various water pumps, ensures no vortex or corresponding hydraulic vibration, reduces hydraulic loss and improves properties of pumps.

The invention provides a system for accurately measuring flow of an engine nozzle. The system comprises a hydraulic source, a measurement and control platform and a clamping platform, wherein the hydraulic source comprises a test medium container and a measurement device, and is used for providing test medium with stable pressure for the system; the measurement and control platform comprises a hydraulic pipeline and a measurement and control system, and is used for stably transferring the test medium with pressure output by the hydraulic source to the clamping platform and feeding back a signal according to the pressure of the clamping platform, so that the test medium is transferred with a stable preset pressure value; and the clamping platform comprises a liquid storage platform, a clamping device and a measurement device, and is used for mounting and fixing the nozzle and providing real-time liquid flow pressure with reliable sealing. Through measuring the flow of the nozzle, the affect of the nozzle on power, combustion sufficiency and stability of the engine is ensured. The system has the advantages of high measurement efficiency, high measurement precision, high intelligent degree and the like, and can be used for measuring the flow of the engine nozzles in various models.

The invention provides a pipeline gas pressure stabilization regulating system including a pressure monitoring system and a pressure regulating system, the pressure regulating system includes a fuel tank, a first pressure release valve and solenoid switch connected in turn, the solenoid switch connects to a first buffer vessel set, the other end of the first buffer vessel set connects to a regulating valve set by a second buffer vessel set, then connected to a combustor on the one hand; on the other hand the other end of the first buffer vessel set separately connects a secure boot flame and an igniter by a general pressure reducer; a gas pressure sensor in the pressure monitoring system is arranged on the top of the first buffer vessel set and the second buffer vessel set. The inventive system can reduce gas pressure wave motion for maintaining stabilization of the pipeline gas pressure.

The invention discloses a distributed water mixing and pressurized heat supply system having a decoupling function and a design method of the system, relate to a heat supply system and a design method thereof, and aims to solve the problems of high invalid energy consumption and mutual coupling of hydraulic regimes existing in the conventional directly-connected centralized heat supply system, the problems of mutual coupling of hydraulic regimes and poor system adaptability existing in a distributed pump system, the problems of mutual coupling of hydraulic regimes and the presence of invalid energy consumption existing in the conventional water mixing system, and the problems of high invalid energy consumption and large diameter of an equalizer tank existing in an equalizer tank system. The distributed water mixing and pressurized heat supply system comprises a heat source, a heat source circulating water pump set, a water supply pipeline, a water return pipeline and three types of heat users, wherein the inlets of a first type of heat supply network users are provided with water mixing pumps and differential pressure valves; the inlets of a second type of heat supply network users are provided with water mixing pumps, booster pumps and decoupling equipment; and the inlets of a third type of heat supply network users are provided with water mixing pumps. The distributed water mixing and pressurized heat supply system is applied to heat supply systems.

The invention discloses a bypass defrosting device with four-port valves, which comprises a compressor, a gas-liquid separator, a high-pressure reservoir, at least two four-port valves, at least two groups of heat exchanging components in a condensing side, and at least two groups of heat exchanging components at an air side. The first port of each four-port valve is connected with the vent of the compressor, and the second port of each four-port valve is connected with one end of each heat exchanging component at the condensing side, the other end of the heat exchanging component is connected with the high-pressure reservoir; one end of each heat exchanging component at the air side is connected with the high-pressure reservoir, the other end of each heat exchanging component at the air side is respectively connected with the third port of the corresponding four-port valve, the input end of the gas-liquid separator is connected with the fourth port of each four-port valve, and the output end of the gas-liquid separator is connected with the intakeport of the compressor. The bypass defrosting device with the four-port valves has small system pressure fluctuation during defrosting, higher reliability and stability, good defrosting effect, short defrosting time and simple structure, and can implement heating and defrosting at the same time.

The invention discloses a test board for flow rate pressure of a pressure regulating valve, which comprises an oil tank, wherein the oil tank is connected with an oil inlet pipeline, and the oil inlet pipeline is connected with an oil pump, a flow rate meter and a pressure sensor and is connected to the pressure regulating valve to be tested, and the pressure regulating valve to be tested is connected with an oil return pipeline; the oil return pipeline is connected with the pressure sensor and is connected to an oil return box; and a data acquiring and controlling device is connected to a flow rate meter and the oil pump to control the oil pump to output a certain quantity of test liquid, wherein the data acquiring and controlling device comprises a processor which is connected to the pressure sensor and used for processing the acquired flow rate pressure data. The test board for the flow rate pressure of the pressure regulating valve achieves the multifunctional test capability to the pressure regulating valve, can simulate the working states of the pressure regulating valve under multiple conditions, and has high automation and intellectualization and high efficiency.

The invention relates to a trajectory planning method for variable speed drop of composite press. The trajectory planning method comprises: first, the differential command signals are input in a proportional pilot control valve to control the circulation drop of the press and collect signals of the movable beam displacement, return cylinder pressure and instruction; then, the movable beam displacement is treated by differential method to get the falling velocity signal of movable beam and the mathematical model of valve flow is obtained by training the collected parameters by neural network algorithm; then, combining the force balance equation of the return cylinder and the continuity equation of the flow, a comprehensive mathematical model of the falling system is built; finally, with the error integral of the return cylinder pressure as the optimization index, the improved genetic algorithm is used to optimize the cubic wire interpolation trajectory, and the control trajectory of the moving beam falling is obtained. The trajectory planning method for variable speed drop of composite press adopts the movable beam falling instruction path planning method can effectively avoid the impact of rigid and flexible impact system, restrain the system pressure fluctuations and improve the efficiency and accuracy of trajectory planning activities to enhance the transmission beam falling, improving engineering adaptability.

The invention aims to provide an electromagnetic control pressure-storage and pressure-stabilizing oil sprayer. The oil sprayer comprises an oil sprayer head, an oil sprayer body, a flow limiting assembly, a needle valve reset spring, a spray nozzle, a needle valve, a cap nut, an electromagnetic valve assembly and a locking sleeve. The structure of the flow limiting assembly is adopted in the oil sprayer, therefore, fuel oil economy reduction caused due to the fact that the oil sprayer sprays oil abnormally and interruptedly can be effectively avoided and the working reliability of oil sprayer is guaranteed. A pressure storage cavity in the oil sprayer body can reduce pressure fluctuation caused in the fuel oil injection process and facilitate accurate control over oil spraying stability. Meanwhile, when the oil sprayer is used in a common rail fuel oil system, the structural size of a common rail pipe can be reduced, therefore, the requirements for strength of materials of the common rail pipe are reduced, the service life can be prolonged and the spatial utilization rate can be increased. The action process of the needle valve is directly driven by a solenoid valve, the response speed of the needle valve is high, the control precision is high, oil spraying is regular, flexible and changeable, the dynamic property and the economy of a diesel engine are effectively improved, and therefore the diesel engine can meet stricter emission regulations.

A load economic distribution control method based on a flow balance group is used for the economic distribution control of the load of a boiler and a stream turbine group in a piping-main scheme parallel operation mode, can be conveniently realized by supervising and controlling a two-stage computer system structure, and has the characteristics of good rapidity of distribution control, small pressure fluctuation of a main pipe, remarkable reduction of coal consumption and the like. When a control system in a piping-main scheme thermal power plant conducts load distribution on a parallel operation machine set, the control method comprises the following steps: (1) dividing a flow supply and demand balance group in the principle of proximity at the moment of each timing load distribution; (2) executing an overall situation load economic distribution task according to a given load demand at the moment of each timing load distribution; (3) judging whether a new lifting load demand appears or not in the stable operation process; (4) judging whether a malfunction and blowing-out signal appears or not in the operation process; (5) judging whether a malfunction and stopping signal appears or not in the operation process.

The invention relates to a valve for a piston pump, wherein the valve (22) comprises a valve closure body (10) and a valve seat (26) disposed longitudinally facing to the valve closure body (10); the valve closure body (10) comprises a cylindrical guide section (12) and a hemispheric sealing section (14) longitudinally facing to the cylindrical guide section (10) and facing to the valve seat (26); the sealing section is used for selectively closing and opening a hole (30) enclosed by the valve seat (26); according to the invention, the sealing section (14) comprises at least one channel opening (16) which is located out of the hole (30) enclosed by the valve seat (26) under the state that the valve (22) is closed, and extended into a channel (18) in the valve closure body (10) substantially extending along a flow direction.