83results about How to "Fast boost" patented technology

The invention discloses an impulse test system of a hydraulic hose. The system comprises a hydraulic impulse loading system and the like. The hydraulic impulse loading system comprises an oil source and the like. The oil source comprises a main oil tank and the like. The main oil tank is respectively connected with a hydraulic pump and an overflow valve. The hydraulic pump is connected with a one-way valve I which is respectively connected with a hydraulic control valve, an electro-hydraulic servo valve, a pressurizing cylinder and an energy storage device I. The electro-hydraulic servo valve is connected with the hydraulic control valve, and an energy storage device II, the hydraulic control valve and a tested hydraulic hose connecting block I are connected with the pressurizing cylinder. The pressurizing cylinder, the electro-hydraulic servo valve, the hydraulic control valve and the overflow valve are connected with the main oil tank. A temperature control system comprises a throttling hole, a one-way valve II, a high temperature oil tank and a radiator. A tested hydraulic hose connecting block II and the radiator are connected with the throttling hole. The radiator is communicated with the high temperature oil tank. A one-way valve II is connected with the high temperature oil tank, and the one-way valve II is communicated with the tested hydraulic hose connecting block I. The electro-hydraulic servo valve is connected with a controller.

The disclosed device comprises: a gas dynamic system, a water-filling exhausting system to fill the pressure media into the high-pressure device rapidly and exhaust gas, a pressure up-down system for compression, holding and release; a detection control system to monitor and control whole process and output data, and a security protection system to protect when over pressure. This invention fit to different test and analysis with stable pressure and well reliability.

The invention relates to a low-power rapid-boost FLASH charge pump control circuit. The low-power rapid-boost FLASH charge pump control circuit comprises a programming erase control circuit, a voltage regulating circuit, a voltage reducing circuit, a clock generating circuit, a four phase clock circuit, a charge pump and a voltage stabilizing circuit. The voltage reducing circuit is divided into two paths, one path is used for quick start and works when the output voltage of the charge pump is low, the other path is used for the voltage trimming of the charge pump and works when the output voltage of the charge pump approaches a target value, and the voltage reducing circuit reduces the voltage through a reverser biased diode and a forward biased diode in order to reduce power consumption; the clock generating circuit is used for generating a clock required by the work of the charge pump, the frequency of the clock is adjustable, and in the early start stage, the clock runs in a fastest frequency within an adjustable range, and the voltage of the charge pump fast rises; and when the voltage of the charge pump approaches the target value, the clock frequency is trimmed according to the feedback voltage of the charge pump in order o maintain the voltage of the charge pump in a reasonable range. The control circuit reduces the power consumption of a Flash memory and increases the programming erasing speed of the Flash memory.

The invention discloses a balloon dilatation pressure pump for interventional therapy, which comprises a rack, a handle part, a sleeve with a blind nut, a pressure meter and an extension pipe, wherein the handle part is sleeved outside the rack and can be movably inserted into the sleeve for use, one side of the rack is provided with a thread, the inner wall of the blind nut on the sleeve is provided with a corresponding thread, the rack is meshed with the blind nut through the threads, the pressure meter is arranged at one end of the sleeve, the extension pipe is connected to the protruding part of the sleeve, the angle Theta of the thread on the rack is 40-50 degrees, and the pressure meter is connected with the sleeve through the thread. The invention meets the requirements of the pressure pump about smooth supercharging, pressure maintaining and rapid pressure releasing through reasonable design of the thread angle on the rack, improves the air tightness and the durability of the product through the thread connection of the pressure meter and the sleeve, and increases the visibility in an operating room through the fluorescence panel design of the dial of the pressure meter.

The invention discloses a high-energy-rate pulse impact hydraulic-forming method and belongs to the field of high-speed formation of materials. According to the high-energy-rate pulse impact hydraulic-forming method, the advantages of high-speed impact forming and the advantages of pulse hydraulic forming are combined, and an impact body which moves at a high speed impacts liquid media repeatedly to complete incremental forming of a part. According to the process of each time of impacting, an impact power source drives the impact body to move at a high speed, the impact body which moves at a high speed impacts the liquid media, the kinetic energy of the impact body is instantly converted into the pressure energy of the liquid media, and thus rapid deformation of a workpiece is completed. According to the method, the overall output energy can be controlled accurately, so that the energy transmission rate, namely energy used for workpiece forming, is controlled accurately, and the required part shape is obtained through multiple times of pulse impact; the deformation of each pass can be controlled accurately, the forming time is short, the strain rate of materials is high (10<3>s<1->-10<4>s<-1>), the forming limit of the materials can be increased, and the mold attaching effect is good; and the high-energy-rate pulse impact hydraulic-forming method can be used for precise formation of magnesium alloy, aluminum alloy, titanium alloy and other alloys difficult to deform.

The invention discloses a production method for colored PET industrial filaments. A chip spinning one-step method production line is employed; when PET melt flux passes through a melt flux pipeline, color oil and auxiliary agent are added to the PET melt flux via an injection port on the melt flux pipeline; then the color oil and the PET melt flux are evenly mixed via a plurality of novel static mixers in the melt flux pipeline; and the mixed PET melt flux is redistributed into a spinning case or each spinning position. Colored high-strength PET industrial filament possesses even and bright colors, requires short production period and low energy consumption by the use of the production method.

The invention relates to a high-pressure air pump, and belongs to the field of high-pressure air pump manufacturing. The high-pressure air pump comprises a pump cover, air cylinders, pistons, a water cooling device and a pump seat. The air cylinders are composed of the first air cylinder, the second air cylinder and the third air cylinder, the diameters of the first air cylinder, the second air cylinder and the third air cylinder are gradually reduced, the first air cylinder, the second air cylinder and the third air cylinder are coaxially arranged, the pistons are composed of the first piston, the second piston and the third piston, the diameters of the first piston, the second piston and the third piston are gradually reduced, and the first piston, the second piston and the third piston are arranged in the first air cylinder, the second air cylinder and the third air cylinder respectively. The water cooling device is arranged between the second air cylinder and the third air cylinder. The high-pressure air pump further comprises a water cooling detecting system, an automatic lubricating system and an automatic drainage system. The high-pressure air pump has the advantages that the output work pressure is high, the heat radiation structure is designed, the heat radiation effect is good, and the high-pressure air pump can continuously work for a long time; the high-pressure air pump is suitable for being driven by a motor, pressure rising speed is high, and work efficiency is high; an air moisture filtering device is arranged, and the interior of the air pump does not need to be drained even though the air pump is used for a long time.

The invention discloses an electric pressure cooker and a safe uncovering mechanism thereof. The safe uncovering mechanism comprises a cooker cover (8), a fixed cover (1) and a floater (4) as well as a magnetic adsorption part (5) and an electromagnet (7), wherein the fixed cover (1) is arranged in the cooker cover (8), and the floater (4) is arranged on the fixed cover (1) in a floating manner; the magnetic adsorption part (5) is arranged at one end, away from the inside of the electric pressure cooker, of the floater (4); the electromagnet (7) is arranged corresponding to the magnetic adsorption part (5) and fixed on the cooker cover (8). According to the safe uncovering mechanism, uncovering protection is realized by controlling the electromagnet (7), uncovering protection is favorably realized, and uncovering by mistake is prevented; floater floating is facilitated by the magnetic aid, the requirement for the weight accuracy of the floater is lowered, production is facilitated, and the production efficiency is improved; at the initial pressure boosting stage, the floater floats upwards by magnetic force, sealing inside the cooker is guaranteed at the stage, and rapid pressure boosting is facilitated.

The invention provides a polyethylene preparation method, an initiator injection system, and a polyethylene reaction system. The polyethylene preparation method comprises following steps: a first circulating gas is delivered into a pressurizer for pressurizing; a first mixed gas is delivered into a first compressor for pressurizing, wherein the first mixed gas comprises the first circulating gas processed via the pressurizer and ethylene; a second mixed gas is delivered into a second compressor for pressurizing, wherein the second mixed gas comprises the first mixed gas processed via the first compressor and a second circulating gas, the pressure of the second circulating gas is larger than that of the first circulating gas, and pressurizing rate of the second compressor is controlled to be 11 to 13MPa / min; the second mixed gas delivered through the second compressor is delivered into a polymerization unit so as to obtain a reaction product; and the reaction product is delivered through a high pressure circulating gas unit, a lower circulating gas unit, and a extruding granulation unit successively so as to obtain polyethylene and a polyethylene copolymer. The polyethylene preparation method is capable of avoiding a problem in polyethylene preparation that scaling of a reactor in a reaction zone is easily caused.

The invention provides a high voltage rise DC / DC converter. The high voltage rise DC / DC converter can convert a low voltage direct current into a high voltage direct current, can achieve soft switching, and has high work efficiency. The high pressure rise DC / DC converter comprises two portions which are respectively a boost circuit unit and a voltage rise unit. The boost circuit unit is composed of two power switches S1 and S2, and a primary side L 1 of a coupling inductor. A subsidiary side L 2 of the coupling inductor, a capacitor c and a diode D form the voltage rise unit of the high voltage rise DC / DC converter. The voltage rise unit is equivalent to a controllable direct current voltage source, and voltage of the voltage rise unit is related to turn ratios N of the subsidiary side and the primary side of the coupling inductor, and the duty ratio D of a switching tube S1. Compared with an existing high voltage rise DC / DC converter, the high voltage rise DC / DC converter is high in voltage gain, low in voltage stress of devices, and high in efficiency.

The invention discloses a dynamic induction simulation device for broken surrounding rock grouting reinforcement, and a testing method therefor. The device consists of a test piece die, a grouting container, a high-pressure oxygen pressurizer, a sensing apparatus, a dynamic monitoring control system, and other main parts. The simulation of broken surrounding rocks in underground construction is achieved through the combination of mashed rock particles with different diameters. The dynamic monitoring control system is used for the real-time monitoring and control of grouting pressure, so as to enable the grouting pressure to remain steady. An osmotic pressure sensor and a flow sensor are used for the measurement of the osmotic pressure and flow of a rock mass, thereby providing data support for subsequent research.

The invention relates to a hydraulic device with a pneumatic pressurizing oil tank and for an oil liquid hybrid power bus. The pressure of hydraulic oil in the hydraulic oil tank is pressed into an axial plunger pump to form pressure oil supply and form a closed hydraulic system by utilizing air pressure of an air compression device of a motor bus aiming at the shortcomings of use of an open hydraulic system on an oil liquid hybrid power motor bus. The hydraulic device utilizes cylindrical air cylinders and oil cylinders to replace a traditional hydraulic oil tank, has the advantages of being small in size, simple in structure and quick in force exertion. Generation of hydraulic force does not require extra driving force, noise and vibration of the hydraulic system are reduced, and the hydraulic device is suitable to be popularized in and applied to the oil liquid hybrid power motor bus.

The invention discloses a boiler thermodynamic system with smoke wastes as fuels and a method thereof. The system comprises a boiler body, a stokehole hopper, a fire grate, a water-cooled wall pipe, a convection pipe, a coal economizer, an air preheater, an air blower, a dust remover and an induced draft fan; a feeding roller is arranged in the stokehole hopper; a front arch and a back arch are arranged in a combustion chamber; a secondary air device is arranged at the middle part of the combustion chamber; and multiple shock wave dust blowers are arranged on heated surfaces of the water-cooled wall pipe, the convection pipe, the coal economizer and the air preheater. The system can effectively use the smoke wastes of redrying enterprises, and realizes energy recovery and resource reuse; when the boiler thermodynamic system uses the smoke wastes as main fuels, the heat efficiency of a boiler is higher than the heat efficiency of a coal-fired boiler; and the smoke NOx and SO2 and dust emission of the boiler reaches the requirements on a gas-fired boiler in the GB13271-2014 boiler atmospheric pollutant discharge standard.

The invention provides a water supply machine, and belongs to the field of water supply equipment. The water supply machine comprises a water pump, a pressure sensor, a controller and a machine box, wherein the pressure sensor is electrically connected with the controller; a contactless switch is arranged on the water pump; the controller is electrically connected with the water pump through the contactless switch; the pressure sensor is used for sensing the water supply pressure of the water pump; the controller contacts the on-off state of the contactless switch according to the pressure sensed by the pressure sensor. The water supply machine belongs to a water supply machine with the advantages that the water pressure is adjustable; the service life is long; the pressure regulation starting is fast.

A test system of 3D geologic mechanical model is composed of box testing device formed by connecting box cast steel component, angle element and chassis together through high strength bolts; hydraulic loading control system formed by variable - load loading plate with thin jack at top, hydraulic loading control table and oil separator. It features that said loading plate is connected on left and right internal walls of box testing device through thin jack and said loading control table is connected to jack through oil separator and oil pipe.

The invention discloses a transformer verification system and a verification method. The verification system comprises a control cabinet, a self-boosting standard voltage transformer, a current transformer detection table, a two-dimensional code generation device, a code scanning gun and a PC. The control cabinet comprises a program-controlled voltage load box, a program-controlled current load box, a program-controlled transformer calibrator, a linear program-controlled electronic power supply and a control cabinet communication system. A current booster, a standard current transformer and acurrent transformer detection communication system are arranged in the current transformer detection table. A plurality of current transformers can be connected to the current transformer detection table. Error verification of the voltage transformers and the current transformers can be realized, full-automatic simultaneous error verification of multiple current transformers can be completed at the same time under the condition of one-time wiring of only one set of device, the verification efficiency is greatly improved, and manual wiring is less and simple.

The present invention discloses a core clamper constant temperature system and an experiment method thereof. The constant temperature system comprises: a core clamper containing a fluid chamber; a constant pressure pump connected with the inlet of the fluid chamber of the core clamper and used for pressurizing the core clamper; a cooling device, wherein the inlet of the cooling device and the outlet of the fluid chamber of the core clamper are connected and are connected with a switch pipeline in a parallel manner, the cooling device cools the core clamper during the working, and the fluid chamber of the core clamper is communicated with the switch pipeline when the cooling device is in the off-line state; a heating device, wherein the inlet of the heating device is communicated with the outlet of the cooling device and the switch pipeline, and the heating device heats the core clamper through the switch pipeline; and a circulation pump connected between the outlet of the heating device and the inlet of the core clamper so as to form the whole fluid circulation circuit. According to the present invention, the constant temperature system can easily be combined with other devices, and can improve the experiment efficiency.

The invention belongs to a catalytic combustion-supporting additive for fire coals of a pulverized coal boiler of a fuel electric plant use, which is composed of powder and liquor. The manufacturing and the using of the additive is realized according to a mechanism that coal is pulverized to powder by a pulverizer and then is blown into the boiler for combustion, and the application of properties of high dispersivity, high permeability, and high catalysis of a high energy catalyst. The manufacturing method of the additive comprises the following steps: firstly, preparation of the powder, and secondly, preparation of the liquor. The using method of the additive is as follows: adding the additive into coals directly, and sending into a coal pulverizer to operate, so as to improve the quality of the pulverized coal, increase the activity of the pulverized coal, and promote the pulverized coal to combust fiercely and fully in the boiler; and spraying the liquor in vaporous to a high-temperature fire zone in the boiler to react with the baking-hot coal, so as to generate water gas to participate in and help the combustion to emit strong heat. The additive has the advantages of small dosage, good effect, and convenience in using, helps to combust efficiently, and has the effect of decoking and deashing.

The invention discloses an impulse test system of a hydraulic hose. The system comprises a hydraulic impulse loading system and the like. The hydraulic impulse loading system comprises an oil source and the like. The oil source comprises a main oil tank and the like. The main oil tank is respectively connected with a hydraulic pump and an overflow valve. The hydraulic pump is connected with a one-way valve I which is respectively connected with a hydraulic control valve, an electro-hydraulic servo valve, a pressurizing cylinder and an energy storage device I. The electro-hydraulic servo valve is connected with the hydraulic control valve, and an energy storage device II, the hydraulic control valve and a tested hydraulic hose connecting block I are connected with the pressurizing cylinder. The pressurizing cylinder, the electro-hydraulic servo valve, the hydraulic control valve and the overflow valve are connected with the main oil tank. A temperature control system comprises a throttling hole, a one-way valve II, a high temperature oil tank and a radiator. A tested hydraulic hose connecting block II and the radiator are connected with the throttling hole. The radiator is communicated with the high temperature oil tank. A one-way valve II is connected with the high temperature oil tank, and the one-way valve II is communicated with the tested hydraulic hose connecting block I. The electro-hydraulic servo valve is connected with a controller.

The invention discloses 1.0 meter wide sheet molding compound and a molding process thereof. The molding compound comprises the following compositions in portion by mass: 60 portions of + / -10 percent unsaturated polyester resin, 40 portions of + / -10 percent low profile shrinking agent, 1.5 portions of + / -10 percent moistening dispersant, 4 portions of + / -10 percent processing aid, 1.5 portions of + / -10 percent tert-butyl benzoperoxide, 1 portion of + / -10 percent cobalt accelerant, 0.5 portion of + / -10 percent para-benzoquinone, 210 portions of + / -10 percent calcium carbonate, 2.6 portions of + / -10 percent magnesium oxide, and glass fiber which accounts for 18 to 28 percent of total mass of the compositions by mass. The molding process has the advantage that the process can obtain the molding compound with 1.0 meter width, thickened and even surface and good performance.

The present invention relates to a method and device for starting a driving system of a motor vehicle, in particular to a method used for starting the driving system of a commercial vehicle. The driving system is equipped with an internal combustion engine boosted by an electrical exhaust turbine booster, and an engine side or transmission side power output device. According to the overall aspect of the present invention, a motor of the electrical exhaust turbine booster is started depending on the modes of the operation state of the power output device, so that the increased power output needed by the power output device can be provided faster, and accordingly, the rotating speed decrease caused by the power output demands of the power output device can be avoided or at least reduced.

The invention belongs to the field of steroid hormone preparation, and in particular relates to a florfenicol intermediate state compound and a method for preparing the florfenicol intermediate. The method comprises the following steps: adding (4R, 5R)-2-dichloromethyl-4-hydroxymethyl-4, 5-dihydro-5-(4-(methylsulfonyl) phenyl) oxazoline into a prepared ishikawa reagent, uniformly stirring, and reacting to obtain a florfenicol intermediate compound; carrying out fluorination reaction of the florfenicol intermediate compound in a micro-channel reaction system at a temperature controlled to be 130 to 160 DEG C and pressure controlled to be 1.6 to 2.0Mpa to obtain the florfenicol intermediate. The florfenicol intermediate disclosed by the invention is a soluble substance, the reaction container is not blocked when the florfenicol intermediate is prepared by using the micro-channel reactor, and the method is safe and reliable.

The invention discloses a temperature isostatic press furnace temperature uniformity optimization device. The temperature isostatic press furnace temperature uniformity optimization device comprises apressure vessel (1) and is characterized in that the pressure vessel (1) is externally provided with a heater (4) heating a working medium; the bottom of the pressure vessel (1) is provided with a working medium inlet and a working medium outlet, and the heater (4) communicates with the working medium inlet and the working medium outlet which are arranged at the bottom of the pressure vessel (1);a supercharger (3) is arranged between the heater (4) and the working medium inlet of the pressure vessel (1); and a combined pressure relief valve (7) is arranged between the heater (4) and the working medium outlet of the pressure vessel (1). The invention further discloses a temperature isostatic press furnace temperature uniformity optimization method. A working medium is heated at first andthen enters the internal greater circulation, thus, superhigh pressure and furnace (8) interior temperature uniformity are achieved within the temperature range of 200 DEG C or below, and the follow-up processing technology requirements of special new materials are met.

The invention relates to the field of fans, and particularly relates to a blowing or induced draft device for pressurizing combustible and explosive as well as corrosive gases. When a working gas is a hazardous gas which is high-pressure, combustible, explosive, corrosive and the like, as a protective gas is arranged in a pressure vessel, an inside-outside pressure difference of a fan can be decreased; and therefore, higher rising pressure can be safely provided. By using the blowing or induced draft device for pressurizing the inflammable and explosive as well as corrosive gases, the pressure vessel is only needed to be filled with the protective gas, and a magnetic driver is not needed to be arranged additionally; therefore, the manufacturing cost is low; the structure is simple; and the production is easy. According to the blowing or induced draft device for pressurizing the inflammable and explosive as well as corrosive gases, a pressure gauge is adopted to monitor gas pressure in the pressure vessel and a gas inlet; the absolute value of a pressure difference between the protective gas and the working gas is guaranteed to meet the pressure resistance of a shell of the fan; therefore, the safe running of the fan is guaranteed; and moreover, the manual monitoring is not needed.

The present invention relates to a pressure device for mould locking, which comprises a push plate arranged between a mould plate of a mould closing mechanism and a corresponding mould, wherein there is a gap between the push plate and the mould plate, in which gap a pressure bag is provided, the pressure bag being made from a resilient plastic cement and provided on a sidewall thereof with a metal interface to be connected with a hydraulic apparatus for feeding a pressure medium into the pressure bag. As compared to the prior art, the pressure device for mould locking provided in the present invention, used in cooperation with a mould closing mechanism on a related apparatus, overcomes defects of hydraulic mould closing mechanisms, such as complex structure, high cost, low efficiency and easy leakage of oil, as well as overcoming defects of crankshaft-type mould closing mechanisms, such as difficulty in control of mould locking forces, low precision, low wear resistance and short service lifetime.

The invention discloses a charge pump. The charge pump comprises N stages of voltage boosting circuits, wherein N in the N stages of voltage boosting circuits is an integer greater than 1; each stage of the voltage boosting circuit comprises a main capacitor; and in the output direction of voltage signals in the N stages of voltage boosting circuits, the main capacitance value in the former stage of the voltage boosting circuits is higher than or equal to that in the next stage of the voltage boosting circuits. Based on a condition of an unchanged main capacitive area, the main capacitance value in each stage is re-allocated; according to charge conservation, the charges in the next stage of the main capacitor are transmitted by the main capacitor in the former stage; if the main capacitance value of the former stage is greater than or equal to that of the next stage, the quantity of charges transmitted from the former stage to the next stage is increased, so that the speed of boosting the output voltage of the charge pump to a stable value is improved; when the main capacitance value of the former stage is higher, the more charges can be stored; and meanwhile, the capacitance value in the next stage is lower, however, the quantity of charges obtained by the capacitor in the next stage in one time is still increased.

The invention provides a four-column guiding type pressurizing device of a hydrostatic testing machine. The four-column guiding type pressurizing device comprises four guiding columns which are vertically arranged, wherein a pressure bearing plate, a lifting plate and a positioning plate are sequentially installed on the four guiding columns from top to bottom. A second hydraulic cylinder and at least two return stroke standard hydraulic cylinders are installed at the lower end of the positioning plate, a first hydraulic cylinder with no oil port is arranged in the second hydraulic cylinder, the upper end of the first hydraulic cylinder is fixedly connected with the lifting plate, a tubular plunger is vertically arranged in the first hydraulic cylinder, the upper end of the plunger sequentially penetrates through the positioning plate, the lifting plate and the pressure bearing plate to be fixedly connected with the pressure bearing plate, the lower end of the plunger is arranged in the first hydraulic cylinder, the return stroke standard hydraulic cylinders are all connected with the lifting plate and drive the lifting plate to drive the first hydraulic cylinder to move vertically in the vertical direction. The four-column guiding type pressurizing device improves the pressure in a tube to testing pressure fast and stably by adopting an automatic speed control pressurizing mode, is novel and compact in structure, reasonable in layout, high in specific pressure, large in capacity, fast and stable in boosting and improves the safety and stability of the system.

The invention relates to an active buck-boost regulating valve for a three natures detecting device of building doors and windows and curtain walls. By means of the active buck-boost regulating valve, the problems of complex structure, large volume, large land occupation, high manufacturing cost and incapability of ensuring the buck-boost speed in the prior art are solved. The active buck-boost regulating valve is characterized in that a first exhaust opening, a second exhaust opening, a first air outlet and a second air outlet are arranged on the right end cover of a cylinder body; a fan air inlet and a fan air outlet are arranged on the left end cover of the cylinder body; a negative pressure cavity and a positive pressure cavity are arranged in the cylinder body; a servo motor is arranged in the middle of the right end cover and a fan plate is connected through a fan plate connection shaft; and a first ventilation opening and a second ventilation opening are symmetrically arranged on the fan plate. In the invention, the regulation of pressure fluctuation, the reversing of positive and negative pressures and the symmetry of buck-boost processes are integrated to a whole, therefore, the active buck-boost regulating valve has the beneficial effects of simple structure, small volume and low cost, high boost or buck speed and stable running, controls air volume by changing the sectional areas of the exhaust openings and the air outlets through the coincidence conditions of the fan plate as well as the exhaust openings and the air outlets, and realizes the reversing of positive and negative pressures through the positive rotation or the reversal rotation of the fan plate.

The invention provides an accurate method for verifying pressure of a low-pressure instrument. A standard meter and a calibrated meter are connected with a verification device; a pressure source provides rated pressure to a filter reducing valve; the pressure entering the filter reducing valve is reduced to the working pressure required by a setter by adjusting the filter reducing valve; no less than 5 pressure calibration points are selected uniformly in the pressure value range of the calibrated meter, the setter is adjusted to output pressure signals in the increase or decrease direction, and when the pressure value of the standard meter points to each pressure calibration point, a stop valve is turned off; a fine tuning handle, a precise fine tuning handle and a pressure release valveon a pressure fine tuner are adjusted to enable the pressure value of the standard meter to be stabilized on each pressure measurement point, and then, the pressure value of the calibrated meter is observed; and when the intrinsic error and variation of the pressure value of the calibrated meter at each pressure calibration point do not exceed the permissible error required by instrument accuracy,the calibrated meter does not need to be adjusted, or otherwise, the calibrated meter needs to be adjusted.

The invention relates to an alertor, in particular to a low-power-consumption security and protection alertor. The low-power-consumption security and protection alertor comprises a buzzer shell, a buzzer cover plate and a piezoelectric sheet, wherein the piezoelectric sheet is fixed in the buzzer shell, the buzzer cover plate is installed at the outer side of the piezoelectric sheet in a covering mode, a pronunciation hole which protrudes outward is formed in the buzzer shell, and the pronunciation hole is communicated with the piezoelectric sheet. The low-power-consumption piezoelectric security and protection alertor further comprises a sound-amplifying chamber. A horn-shaped connecting port which is matched with the pronunciation hole is formed in the sound-amplifying chamber, a reflex sound-amplifying channel is connected with a flaring end of the horn-shaped connecting port, and the other end of the horn-shaped connecting port is connected with the pronunciation hole. By means of the low-power-consumption piezoelectric security and protection alertor and the reflex of the sound-amplifying chamber, a function of sound amplification is achieved. Meanwhile, frequency is reduced through a sound guiding column, and boost is further improved by combination of the sound-amplifying chamber and the sound guiding column. Considering a gap can exist when the horn-shaped connecting port is connected with the pronunciation hole, thus a gasket is adopted to seal the gap, and low sound pressure caused by air leakage is avoided.