57results about How to "Eliminate water hammer" patented technology

The invention discloses a one-frequency one-pump constant pressure water supply control system, which comprises a control unit (6) for controlling the operation of the system and controlling the output frequencies of frequency converters, a human-machine interface (7) for setting parameters of the system and monitoring operational data, the frequency converters (5a, 5b and 5c) for controlling the rotating speeds of water pump motors, and sensing instrument units (1, 3 and 4) connected with the control unit and used for acquiring external feedback information, wherein according to the control system, water pumps (2a, 2b and 2c) in a controlled pump group are matched with the frequency converters and controlled by adopting a common-frequency and common-speed control technology to implement constant pressure water supply.

The invention discloses a check valve comprising a valve seat and a valve flap, in particular, the check valve comprises a damper arranged on the inner cavity wall of the valve seat, wherein the end part of the damper are connected with the valve flap through a flexible element. The damper produces reverse resistance to the valve flap when the valve flap approaches the closed position of the valve flap; the closing speed of the valve flap is slowed down, and the impact force to the sealing surface of the valve seat is reduced. The check valve has a simple structure, can effectively eliminate the impact and water hammer between the valve flap and the sealing seat, and prevents the media leakage in the valve cavity.

A water supply device for high or middle high buildings includes input pipe connected to water main with pressure sensor, electromotive valve, check valve installed on, and a protector also installed between the check valve and water main; outlet pipe connected to customers with pressure sensor installed on; two groups of pressure enhancing pump between the input and output pipe, the pumps are put in anti-fluctuation shell and with input butterfly valve fixed to the front, check valve and output butterfly valve fixed to the back; an airbag isobaric tank connected to the joint position of the pump line to output pipe; a programmable frequency conversion controller linked to pressure sensors, valves and pumps; a chamber on the base to posit pump lines, isobaric tank and the controller; a water box on the base with its floating valve installed between the input electromotive valve and check valve, water box's outlet connected to the front of pump line, check valve also installed on the output line of the water box, both the floating valve and the check valve are linked to the controller.

This invention relates to a water-save time delay valve device in toilet in which, a center film valve core capable of concave-convex floating is mounted on the inlet valve base shaped in a round concave glue piece, an orifice nozzle is insertedin the center with a through needed in the orifice, a decompressing valve is set on an abnormal inner cover implied solid button made of compound material, rigid outside and soft inside, changeable by concave and convex. The decompressing valve is open or close either by hand or foot when fixing the valve on the ground since the ground pollute can't enter into the solid implied button.

The invention provides a buffer and diversion water hammer eliminator which comprises an inner piston buffer part and an outer steady-pressure diversion part which are coaxially arranged inside and outside, wherein the inner piston buffer part comprises an outer wall of the inner piston buffer part as well as an upper piston and a lower pressure regulating piston which are arranged inside the inner piston buffer part; the lower pressure regulating piston is connected with an upper piston through a pre-pressing spring; the top and the bottom of the outer wall of the inner piston buffer part are respectively connected with upper and lower sealing plates; a sealing flange is arranged above the upper piston; the outer wall of the inner piston buffer part is provided with a pressure discharge hole; the outer steady-pressure diversion part comprises an outer wall of the outer steady-pressure diversion part, wherein the outer wall of the outer steady-pressure diversion part is arranged on the outer part of the outer wall of the inner piston buffer part, and the top and the bottom of the outer steady-pressure diversion part are respectively connected with outer walls of the outer steady-pressure diversion parts of the upper and the lower sealing plates; and a breathing water drain-off valve is arranged outside the outer wall of the outer steady-pressure diversion part. The invention further provides a using method of the buffer and diversion water hammer eliminator. The buffer and diversion water hammer eliminator can effectively eliminate a water hammer phenomenon in a water supply process of a water pump, so that a pipe network is kept at stable water pressure, and therefore, safety of a water supply system is guaranteed.

The invention relates to a two-phase damping axial flow type check valve which can adjust closing time. A valve seat is arranged on the inner front part of the valve body, a valve core is arranged in the valve body, the valve core is connected with a valve shaft, a damping cylinder body is arranged in the valve body, the inner front end of the valve body is provided with a sidewise pipe communicated with the valve body, a throttle valve is arranged in the sidewise pipe, the front end of the damping cylinder body is provided with a valve axial hole, and the rear end is provided with a liquid inlet and outlet hole, the inner cavity of the valve body is provided with a front inner cavity and a rear inner cavity with different sizes of the inside diameters, the inner cavity of the cylinder body is provided with a damping cylinder plug matched with the gap of the front inner cavity, the other end of the valve shaft is connected with the damping cylinder plug by the valve shaft hole, the damping cylinder plug is provided with a directional valve flowing forwards, and the distance between the front end of the cylinder cap and the valve core is the same as the distance in which the damping cylinder plug can move in the cylinder sleeve. The invention selects different structural parameters during design to adjust the closing time of the check valve in the two sections. When the invention is used, the openness of the throttle valve can be manually adjusted to adjust the sliding speed of the damping cylinder plug, and therefore, the invention has the characteristic of optimal closing applicable to the transportation state of liquid.

The invention provides a haze-removing, dedusting and cooling system for buildings, and relates to the field of the buildings. The haze-removing, dedusting and cooling system comprises a booster water pump, a water supply pipe, a water distribution pipe, branch pipes and a plurality of nozzles which are arranged on the top of a building, wherein the water supply pipe, the water distribution pipe and the branch pipes are orderly communicated; the input end of the booster water pump is connected with a water source, and the output end of the booster water pump is communicated with the water supply pipe; the nozzles are connected with the branch pipes and arranged around the buildings. The haze-removing, dedusting and cooling system breaks through the traditional thinking, corresponding spraying equipment are additionally mounted at the top of the conventional buildings and used for spraying atomized water around the buildings, and therefore the purpose of improving the micro-climate of the buildings is achieved. If most of buildings in the city adopt the haze-removing, dedusting and cooling system, the microclimatic environment of whole city can also be improved. The haze-removing, dedusting and cooling system only consumes small amount of electricity and atomized water, therefore being more energy-efficient and realizing better environmental protection.

The invention relates to a pressure limiting and stabilizing valve, pertains to the pressure controlling arrangement for tap water, which comprises a water inlet, a casing of a water outlet, and an upper cover and a lower cover. The upper cover is sealedly connected with the casing through a flexible upper seal film; the lower cover is sealedly connected with the casing through a flexible lower seal film; between the water inlet and the water outlet, a partition board with a water-through port is provided; between the upper and the lower cover, a control rod is provided; the inner and outer side of the flexible upper seal film and the flexible lower seal film are provided with an upper cover support, an upper film presser, as well as a lower cover support and a lower film presser for sealedly connecting the controlling rod; on the controlling rod, a seal piece corresponding to the water-through port is fixed; the partition board is connected with a limit; on the controlling rod between the limit and the lower film presser, a spring is provided. The invention is of small size, high strength, high practicability, integrates a plurality of such functions as pressure limiting, stabilizing, and water-hammer eliminating, etc., allows the end users of the water supply pipe network from the municipal engineering not worrying about any water leakage because the water treatment system is damaged by high pressure.

The invention relates to a double-aperture adjustable slow-closure control valve for a water pump, which comprises a main valve and a control device. A diaphragm and a spring are arranged between a valve body and a valve cover, wherein a console cabinet is arranged between the diaphragm and the valve cover and the console cabinet is provided with an inlet connecting pipe and an outlet connecting pipe connected with the inlet and the outlet of the valve body respectively. The invention is characterized in that the inlet connecting pipe is provided with a normally open first electromagnetic valve and the outlet connecting pipe is provided with a normally open second electromagnetic valve and a normally closed third electromagnetic valve. By the control of three electromagnetic valves to the main valve, a closing valve of the water pump starts, a main valve undergoes a double-aperture control, and the main valve realizes two closing stages control such as quick-closure and slow-closure. The invention has the advantages of energy saving, flow regulation and two-level flow outlet, elimination of a water hammer and the like. The invention is used for the outlet pipe control for water pump of water supply system in fire fighting and architecture.

The invention discloses a quick-opening slow-closing water hammer relief valve. The quick-opening slow-closing water hammer relief valve comprises a valve body and a sleeve, wherein the valve body is connected with a valve cover; a valve seat is arranged on a flow channel in the valve body; an opening-closing valve clack which can be sealed with the valve seat is arranged in the valve body; the valve clack is connected with a valve rod; the sleeve of which one end is open penetrates out of the valve cover and is fixedly connected with the valve cover; the valve rod movably extends into the sleeve; the side wall of the valve rod is sealed with the wall of an inner hole of the sleeve; the wall of the sleeve is connected with a drive media pipeline; the drive media pipeline is communicated with the inner hole of the sleeve; the other end of the pipeline is connected with a communication container; and the pipeline is connected with a one-way throttling valve. By using the water hammer relief valve, a water hammer can be opened and eliminated quickly and can be closed slowly at the same time, so that a secondary water hammer generated because of closing the valve too fast is avoided. The quick-opening slow-closing water hammer relief valve has a simple and compact structure.

The invention relates to a water bath vaporizer provided with a vapor-water mixer. The water bath vaporizer is mainly applied to the fields of petrochemical engineering, natural gas, and air separation, is used for vaporizing liquefied natural gas, liquid oxygen, liquid nitrogen and the like, and also can serve as a peak-shaving vaporizer for vaporizing liquefied natural gas to be applied to various levels of natural gas receiving stations, bunkering stations or peak-shaving stations of docks, cities and the like. A cavity is formed in a shell, and a vaporizing tube bundle is arranged in the cavity; a circulating pipeline is communicated with the cavity; and a vaporizing inlet pipe and a vaporizing outlet pipe are communicated with the vaporizing tube bundle. The water bath vaporizer is characterized by also comprising the vapor-water mixer, wherein the vapor-water mixer is communicated with a vapor inlet pipe, the cavity and the circulating pipeline respectively; and the vapor-water mixer is fixed on the middle lower part of the shell. The water bath vaporizer is reasonable in structural design and can avoid water-hammer phenomena.

The invention discloses an intelligent monitoring water purifying machine applicable to a hospital disinfecting and supply center. A running water inlet is connected with a water hammer arrestor; the water hammer arrestor is connected with a composite-filter core filtering device; the composite-filter core filtering device is connected with a booster pump; the booster pump is connected with a water inlet of a RO membrane filtration device; a clean water outlet of the RO membrane filtration device is connected with a clean water pipeline; a concentrated water outlet of the RO membrane filtration device is connected with a concentrated water pipeline; a water quality sensor and a tee joint are sequentially arranged on the clean water pipeline; one end of the tee joint is connected with a water outlet; the other end of the tee joint is connected with a pressure water storage tank; a cleaning pipe is connected onto a pipeline between the tee joint and the pressure water storage tank, and connected with a cleaning air pump. Through the adoption of the intelligent monitoring water purifying machine, the water purifying efficiency and the water purifying quality are improved, so that the intelligent monitoring water purifying machine is worthy of large-scale popularization and application.

The invention provides an elevating type hydraulic slow-closure silencing check valve and relates to a check valve which is mounted on a pipeline and used for preventing media in the pipeline from flowing back. The elevating type hydraulic slow-closure silencing check valve is mainly designed to solve the problem that an existing check valve cannot reduce water hammers. The elevating type hydraulic slow-closure silencing check valve comprises a valve body, a valve body support is cast with the valve body into a whole, a sealing base is arranged in the valve body, a sealing base support is fixedly arranged on the sealing base, a piston rod is fixedly arranged on the sealing base support, the piston rod is arranged in the inner cavity of a valve rod, a rear cap is arranged on the wall of the inner cavity at the rear end of the valve rod, a water in-out hole is formed in the rear cap, the valve rod is arranged on an opening of the valve body support, a valve clack is fixedly arranged at the front end of the valve rod, a guide sleeve is arranged on the wall of the inner cavity of the valve rod, the guide sleeve is connected with the valve clack through a pressing cover, the outer circle of the valve clack is contacted with the sealing base, a sealing ring is arranged on the contact face of the valve clack and the sealing base, one end of a spring sleeved on the outer wall of the valve rod abuts against the valve body support, and the other end of the spring abuts against the valve clack. The elevating type hydraulic slow-closure silencing check valve has the advantage that the valve clack has a slow-closure function.

A piston for well-drilling pump is composed of main body, piston rod, sealing ring installed at front part of main body, the sealing ring positioned at the contact surface between main body and piston rod, and air blocking ring which is a V-shaped, trapezoidal or V-shaped rubber ring. Its advantages are no water hammer, and high sealing performance.

The invention discloses a water hammer eliminating and pressure reducing device for valve protection. The water hammer eliminating and pressure reducing device comprises a first connecting pipe, a device body and a second connecting pipe which are sequentially arranged from left to right. The water hammer eliminating and pressure reducing device has the advantages that in the water hammer eliminating and pressure reducing device, on one hand, in a first straight plane, a first inclined plane, a second straight plane, a second inclined plane and a third straight plane with the widths constantlyincreased, according to the Bernoulli principle, the water pressure is gradually reduced when the width is gradually increased; on the other hand, water flow constantly extrudes a plurality of pistonplates, a second spring is compressed, air in a first compression cavity and a second compression cavity passes through a first communication pipe and a second communication pipe to be pressed into first flow stopping bags and second flow stopping bags, the first flow stopping bags and the second flow stopping bags in a plurality of acting pieces can form flow stopping planes for closing a waterpassing port, and valve impacts are avoided; and due to compressibility of air, a third compression cavity can further achieve the pressure reduction function, the water hammer is thoroughly eliminated, the structure is simple, and the manufacturing cost is low.

The invention discloses a method and device for efficient and energy-saving sludge treatment. The method of sludge treatment comprises the steps: the sludge first enters the preheating unit, and afterpreheating to 60 degrees or more, directly enters the thermal hydrolysis unit, and the high temperature pressurized steam generated after the end of the thermal hydrolysis is returned to the preheating unit to preheat the sludge. The device is a thermal hydrolysis device, including a mounting seat, a tank body, an air inlet pipe, an air guiding pipe, a nozzle, a sieve cylinder, a card slot, a loading bin, a motor, an exhaust pipe, a multi-stage electric push rod, a shaft rod, a connecting rod , block, rotating rod, mixing blade, discharge tube, brush and filter net. The method and the deviceaccelerate the speed of thermal hydrolysis, can make the steam and sludge mixing effect better, and also save the cost, greatly improve the work efficiency, reduce the work intensity of the staff, andalso enhance the work. Practicality.

The invention provides fully-enclosed flow-stabilized and pressure-superposed energy storage water supply equipment. According to the fully-enclosed flow-stabilized and pressure-superposed energy storage water supply equipment, the problem that a common pressure-superposed water supply product has no water storage capacity or has extremely small water storage capacity is solved, and dual functionsof water storage and energy storage are introduced into a pressure-superposed water supply system; the water contention degree of a plurality of secondary water supply stations to a municipal primarywater supply pipe network is greatly reduced, the reactive power loss of water supply is greatly eliminated, the water supply efficiency is improved, and continuous, safe and high-quality water supply for users can still be realized under the condition that the flow quantity and pressure of a municipal tap water pipe network cannot meet user requirements continuously; even under the condition that the water supply of the municipal tap water pipe network is completely cut off, the water supply still can continue for a number of minutes to a number of hours; positive pressure full enclosing ofwater storage facilities can be realized, the purposes of chlorine maintaining, self cleaning and no cleaning are achieved, and the fully-enclosed sanitary safety requirement in the Chinese water supply standard is fully met; and the blank that no secondary water supply products of other forms exists between pressure-superposed water supply and water tank (pool) water storage water supply in the secondary water supply products for many years is filled up.

The invention relates to a slow closing control device of a check valve. The slow closing control device comprises an intake pipe, a first connecting pipe, a second connecting pipe, a cylinder and a hydraulic cylinder; a first inner cavity is formed in the cylinder; a first piston is arranged in the first inner cavity for dividing the first inner cavity into a first cavity body and a second cavity body; the first piston is extended with a first piston rod in the first cavity body; a second inner cavity is formed in the hydraulic cylinder; a second piston is arranged in the second inner cavity for dividing the second inner cavity into a third cavity body and a fourth cavity body; a second piston rod is arranged on the second piston; the first piston rod and the second piston rod are linked and matched; a throttle pipe is connected between the third cavity body and the fourth cavity body; a one-way throttle valve is arranged on the throttle pipe. The slow closing control device of the check valve, provided by the invention, can control the closing time of the check valve to eliminate a water hammer of the pipe so as to achieve a preferable effect of protecting safety of a pipe network system.

The invention belongs to the technical field of pipeline valves, and particularly relates to a hydraulic control ball valve system and a control method. The hydraulic control ball valve system comprises an eccentric ball valve, a hydraulic station and a control cabinet, and the hydraulic station comprises oil cylinders, an oil supplement pump, an energy accumulator, a first electromagnetic valve,a second electromagnetic valve, a third electromagnetic valve, a fourth electromagnetic valve, a fifth electromagnetic valve and a sixth electromagnetic valve. According to the hydraulic control ballvalve system and the control method, the adopted eccentric ball valve is improved on the basis of a full-bore eccentric ball valve, the characteristic that the hydraulic loss of the full-bore eccentric ball valve is zero is inherited firstly, in addition, the abrasion is small, and the service life is long; and then a set of intelligent hydraulic control system (namely the control cabinet and thehydraulic station) is additionally arranged, and through the design of the excellent hydraulic control system and an intelligent control system, the effect of completely eliminating the water hammer can be achieved.

The invention discloses a check valve comprising a valve seat and a valve flap, in particular, the check valve comprises a damper arranged on the inner cavity wall of the valve seat, wherein the end part of the damper are connected with the valve flap through a flexible element. The damper produces reverse resistance to the valve flap when the valve flap approaches the closed position of the valveflap; the closing speed of the valve flap is slowed down, and the impact force to the sealing surface of the valve seat is reduced. The check valve has a simple structure, can effectively eliminate the impact and water hammer between the valve flap and the sealing seat, and prevents the media leakage in the valve cavity.

The invention discloses a dye vat water circulation system, and belongs to the field of textile printing and dyeing equipment. The dye vat water circulation system comprises a dye vat (1) and a water injection pump (6) for injecting water into the dye vat (1), and a heat exchanger is arranged in the dye vat (1). The dye vat water circulation system is characterized in that a recycled water tank (9) is arranged, a heat exchange water outlet of the heat exchanger is connected into the recycled water tank (9) through a pipeline, a water inlet of the water injection pump (6) is connected to the bottom of the recycled water tank (9) through a pipeline, a water outlet of the water injection pump (6) is connected to the top of the dye vat (1) through a dye vat water filling pipe (2), and a water hammer eliminating branch is arranged between the water injection pump (6) and the recycled water tank (9). According to the dye vat water circulation system, secondary application of heat exchange water of the heat exchanger is realized by the aid of the recycled water tank, waste of water resources is avoided, and water hammer in the pipelines is eliminated when the water injection pump stops working.

The invention discloses a countryside household cleanable water purifying machine which comprises a machine shell and a control device. A water hammer eliminator, a resin filter element, an activated carbon filter element, a super filter element, a water storage tank, a rear activated carbon filter element and a cleaning air pump are arranged in the machine shell, and a water inlet is connected with the water hammer eliminator. The water hammer eliminator is in pipeline connection with the resin filter element, the resin filter element is in pipeline connection with the activated carbon filter element, and the activated carbon filter element is in pipeline connection with the super filter element. One end of the super filter element is in pipeline connection with the water storage tank through a three-way valve, the other end of the super filter element is in pipeline connection with the rear activated carbon filter element, the rear activated carbon filter element is in pipeline connection with a purified water outlet, one end of the water storage tank is connected with a cleaning pipeline through a three-way valve, the cleaning pipeline is connected with the cleaning air pump, and the cleaning air pump is electrically connected with the control device. The water purifying machine is easy to use, safe drinking of countryside underground water is guaranteed, and convenience can be brought to daily cleaning.

The invention relates to a micro sound check valve. The micro sound check valve comprises a valve body and a valve deck. A medium inlet channel and a medium outlet channel are formed inside the valve body and communicated with a valve cavity inside the valve body. An opening is formed in the valve cavity and provided with the valve deck, a valve rod is arranged inside the valve cavity and sleeved with a valve clack, the connecting position of the medium inlet channel and the medium outlet channel is a connector, and the valve clack and the connector are sealed. A water hammer can be effectively eliminated, and in this way, it is guaranteed that the performance and the sealing effect of the valve are better, and the service life of the valve is longer.

The invention discloses a photovoltaic control system achieving water supply automatic adjustment through a frequency converter. The photovoltaic control system achieving water supply automatic adjustment through the frequency converter comprises a photovoltaic control module, the frequency converter and a water supply module. The photovoltaic control module is provided with a solar panel, a photo-electricity conversion module, a storage battery, a power module and a motor driver. The frequency converter is arranged on one side of the photovoltaic control module. The frequency converter is provided with a rectifying circuit, a filter circuit, a signal sensor, a light sensor, a drive circuit and a current and voltage signal processing module. The water supply module is arranged on one side of the frequency converter. The water supply module is provided with a controller. A frequency adjuster is arranged on one side of the controller. A flow speed sensor, a liquid level sensor, a data collecting module and a water flow control module are arranged at one end of the controller. The photovoltaic control system achieving water supply automatic adjustment through the frequency converter achieves that water supply is automatically controlled, avoids the situation that other energy sources are consumed to provide electric energy for operation of a drive device and has the effects of saving energy and being environmentally friendly and intelligent.

The invention discloses an isotonic constant-pressure compensator. An exhaust pipeline and a pressure meter are arranged on the upper portion of an expansion tank. An isotonic expansion ball filling inlet is arranged on the right side of the expansion tank. Lifting lugs are arranged on the two sides of the upper portion of the expansion tank. A left baffle plate and a right baffle plate used for dividing the expansion tank into an expansion tank left area, an expansion tank middle area and an expansion tank right area are arranged in the expansion tank. Flow guide holes are machined in the bottom of the left baffle plate and the upper portion of the right baffle plate. Isotonic expansion balls extruding one another are arranged in the expansion tank left area, the expansion tank middle area and the expansion tank right area and are filled with gas. A first water inlet and outlet pipe communicating with a pipeline is arranged at the bottom of the expansion tank right area. A second water inlet and outlet pipe communicating with the pipeline is arranged on the upper portion of the expansion tank left area. A water drain valve is arranged on the pipeline. A drain outlet is arranged inthe middle of the bottom of the expansion tank and communicates with a pollution discharge valve through the pipeline. The pressure of the isotonic constant-pressure compensator can be stable, and the phenomena of water hammers and air hammers of the isotonic constant-pressure compensator can be eliminated. The isotonic constant-pressure compensator has the advantages of being convenient to maintain, low in maintenance cost and the like.

The invention provides a self-exhausting lift type hydrant and relates to the technical field of water conservancy equipment. The self-exhausting lift type hydrant comprises an elbow, an inner pipe, a gland, an outer pipe and a bottom support, wherein the elbow is connected with the inner pipe; the inner pipe moves in the outer pipe; the gland is arranged at the upper end part of the outer pipe; the outer pipe is connected with the bottom support; an exhausting valve is arranged on the bottom support; the exhausting valve comprises an outer mounting shell; a limiting part is arranged on the outer mounting shell; an elastic sealing body for allowing water flow to pass through is arranged at the upper part of the outer mounting shell; a floating ball is arranged between the limiting part and the elastic sealing body; and the floating ball is capable of floating upwards to block a water outlet in the elastic sealing body. By virtue of the design of the exhausting valve, the self-exhausting lift type hydrant provided by the invention is capable of eliminating the water hammer phenomenon; by adopting a valve composite component, the problem of the poor sealing effect of a rubber ring is prevented; the self-exhausting lift type hydrant is simple in structure, convenient to open and close, scientific in manufacturing process, economical, practical, and widely applicable to farm irrigation, water supply and water draining of urban green lands.

The invention discloses a hydraulic plug-type slag slurry pump control valve, it includes the valve body (3) and its base (9), the valve spool (4) installed in the valve body (3) through the valve axle (17), said valve axle (17) is connected with one end of the lever (2), another end of said valve axle (17) is equipped with a heavy hammer (1), the lower end of hydraulic cylinder (6) is hinged on said base (9), said lever (2) is hinged with the piston bar (7) in said hydraulic cylinder (6), the normal open magnetic valve (11) is parallel connected with the one-way valve (12) and then one end of them is connected with the lower cavity of said hydraulic cylinder (6), and another end is connected with the hydraulic station (13) through said oil pipes (10). The invention is a safe hydraulic plug-type slag slurry pump control valve which is mainly used for slag slurry pump outlet and has the functions of preventing inverse flow, starting pump in no-load, releasing water hammer and automatic control, and it can protect the water pump and pipe net equipments effectively.

The invention relates to a double-aperture adjustable slow-closure control valve for a water pump, which comprises a main valve and a control device. A diaphragm and a spring are arranged between a valve body and a valve cover, wherein a console cabinet is arranged between the diaphragm and the valve cover and the console cabinet is provided with an inlet connecting pipe and an outlet connecting pipe connected with the inlet and the outlet of the valve body respectively. The invention is characterized in that the inlet connecting pipe is provided with a normally open first electromagnetic valve and the outlet connecting pipe is provided with a normally open second electromagnetic valve and a normally closed third electromagnetic valve. By the control of three electromagnetic valves to themain valve, a closing valve of the water pump starts, a main valve undergoes a double-aperture control, and the main valve realizes two closing stages control such as quick-closure and slow-closure. The invention has the advantages of energy saving, flow regulation and two-level flow outlet, elimination of a water hammer and the like. The invention is used for the outlet pipe control for water pump of water supply system in fire fighting and architecture.