CN102644604A - Automatic priming device for centrifugal pump - Google Patents
Automatic priming device for centrifugal pump Download PDFInfo
- Publication number
- CN102644604A CN102644604A CN2012101105891A CN201210110589A CN102644604A CN 102644604 A CN102644604 A CN 102644604A CN 2012101105891 A CN2012101105891 A CN 2012101105891A CN 201210110589 A CN201210110589 A CN 201210110589A CN 102644604 A CN102644604 A CN 102644604A
- Authority
- CN
- China
- Prior art keywords
- valve
- output
- pump
- centrifugal pump
- input
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Abstract
The invention discloses an automatic priming device for a centrifugal pump. The automatic priming device mainly comprises a centrifugal pump, a gas-liquid separating tank, a liquid level sensor, a controller, an injector and a valve, wherein the gas-liquid separating tank is connected with a sucking port of the centrifugal pump, the liquid level sensor and a second pneumatic valve; the input of the controller is connected with the liquid level sensor; the output of the controller is connected with an electromagnetic reversing valve; the electromagnetic reserving valve is connected with a first pneumatic valve, the second pneumatic valve and a cut-off valve; and the injector is connected with the second pneumatic valve and is simultaneously connected with the first pneumatic valve through a one-way check valve. According to the automatic priming device disclosed by the invention, the function of automatically priming is achieved and the condition that no cavitation phenomenon always occurs in the operation process of the centrifugal pump can be ensured. In addition, the automatic priming device has the advantages of simple structure, low manufacturing and maintaining cost and stability and reliability in operation and is especially suitable for priming before the start of a ship ballast pump, a bilge pump and an emergency firefighting pump.
Description
Technical field
The present invention relates to a kind of water diversion apparatus, relate in particular to a kind of centrifugal pump automatic water diversion device that does not have suction capacity.
Background technique
Centrifugal pump belongs to vane pump, if the inside does not have water, the blade rotation is to set up vacuum pressure, also just can't suck water, does not therefore have suction capacity for centrifugal pump.But the most suitable ballast pump, bilge pump and the emergency fire pump etc. done of centrifugal pump are pressed the CCS code requirement, and all burr pumps or dual-purpose burr pump all should have self-priming performance; If fire water pump or emergency fire pump are arranged in more than the waterline, also self-priming performance should be arranged.Do not have the problem of suction capacity in order to solve centrifugal pump, all will on pump, add self-priming apparatus.What the self-priming water diversion apparatus was common has two kinds: a kind of is the jet pump formula; It is to do power with electromagnetic valve pressurized air to come the air in the suction pump to form negative pressure through sparger; Its solenoid valve when the startup of pump is switched on simultaneously and is opened the air feed diversion, closes again after the time relay time-delay to quit work.Another kind is the water ring pump formula; It contacts the drive water ring pump through friction clutch and comes the air in the suction pump to form negative pressure with the shaft coupling of pump; This device also needs a little water tank to guarantee that water is arranged in the water ring pump, and when delivery side of pump reached certain pressure, the water pressure pushing clutch shaft made it to throw off with the shaft coupling of pump; At this moment, the water diversion apparatus diversion finishes and quits work.For first kind of diversion mode, at the beginning of pump startup, do not fill water in the pump, but after after a while, just fill water in the pump gradually, therefore, pump can gather air in certain amount in the pump in a period of time that has just brought into operation, and produces cavitation phenomenons.In order to avoid and reduce the generation of cavitation phenomenons as far as possible, should be first diversion recurrence pump, but being pump and diversion, this mode carries out simultaneously; Obvious this mode can impact the working life of pump, and this mode another one deficiency is exactly to be used for example with centrifugal pump as ballast pump; After diversion finished, ballast pump got into normal working, along with the liquid level decline of ballast tank; Whirlpool occurs at horn mouth, when whirlpool bottom during near horn mouth, a large amount of gases will be inhaled into; Therefore need the effect that a kind of device can play diversion badly, can guarantee again in the process of pump operation, do not have a large amount of air all the time and be inhaled into the water diversion apparatus in the pump.For second kind of diversion mode, install relative complex, increased the difficulty and the product cost of installation and maintenance.
CN201288937Y discloses a kind of " self-controlled type centrifugal pump vacuum water diversion device ", and this device mainly is made up of vacuum pump, vacuum tank, the automatic vent sealing valve and the automatic control system that are loaded on water pump relief opening top.Vacuum pump operation produces vacuum water diversion, and automatic vent sealing valve stops water entering vacuum pipe behind the water pump full water, and vacuum tank has formed the degree of vacuum buffer area, and degree of vacuum is controlled the start and stop of vacuum pump automatically, thereby is in full water state when guaranteeing the centrifugal pump standby all the time.This device has self-absorption function and can be the advantage of many pump diversions simultaneously, but some is not enough below existing: the one, because this device is the start and stop according to the vacuum degree control vacuum pump of vacuum tank, degree of vacuum is a relatively more responsive monitoring target; Sensitivity to monitoring element has proposed higher requirement, and the sealing to vacuum tank also has very high requirement simultaneously, gives the Selection and Design of Sealing; The processing of vacuum tank all brings certain degree of difficulty, if vacuum tank has leakage, degree of vacuum will be low; Chain reaction is exactly the vacuum pump running; Just need consumed power accordingly, bring energy waste, frequent start-stop is all influential to vacuum pump or motor in addition; The 2nd, the interface of this device and pump is the steam-expelling port of pump; If the suction inlet of pump near the bottom of liquid goods, has a large amount of gases to be inhaled into, these gases are to be introduced into pump; The back is taken away by vacuum pump; At this moment the operation of pump has been produced and damaged, can not play the early warning protective action, therefore diversion before the startup of inapplicable ballast for cruising pump, bilge pump and emergency fire pump; The 3rd, this device needs to be provided with " automatic vent sealing valve " and prevents that the aqueous reflux in the pump from getting into vacuum tank, only allow the gas in the pump to get into vacuum tank, and the setting of " automatic vent sealing valve " this functional element has brought complexity to device.The manufacturing and the operating cost of device have been increased.
Summary of the invention
The objective of the invention is to overcome the deficiency of existing technology; And a kind of automaticity height, good reliability, simple in structure are provided; And the preceding diversion of the startup that is applicable to ballast for cruising pump, bilge pump and emergency fire pump, and can guarantee that centrifugal pump does not have gas and is inhaled into a kind of automatic water diversion device in the centrifugal pump in operation process.
The objective of the invention is to realize like this: a kind of centrifugal pump automatic water diversion device; Comprise centrifugal pump, knockout drum, liquid level sensor, controller, solenoid directional control valve, pneumatic valve, sparger, one way stop peturn valve and stop valve; It is characterized in that: knockout drum is connected with centrifugal pump, liquid level sensor and second pneumatic valve; The input of controller is connected with liquid level sensor, and output is connected with solenoid directional control valve, and solenoid directional control valve is connected with stop valve with first pneumatic valve, second pneumatic valve; Sparger is connected with second pneumatic valve, is connected with first pneumatic valve through one way stop peturn valve simultaneously.
The lower cavity of said knockout drum is communicated with centrifugal pump intake through pipeline, and upper chamber is communicated with second pneumatic valve through pipeline, and liquid level sensor is arranged on the middle and upper part of knockout drum.
Said controller is made up of input interface, comparison circuit, drive circuit and output interface, and the input of comparison circuit is connected with input interface, and the output of comparison circuit is connected with the input of drive circuit, and the output of drive circuit is connected with output interface.
Said comparison circuit comprises hysteresis comparator, low-pass filter, voltage follower and comparator; The input of hysteresis comparator is connected with input interface; The output of hysteresis comparator is connected with the input of low-pass filter; The output of low-pass filter, the output of voltage follower are connected with the input of comparator, and the output of comparator is connected with the input of drive circuit.
Said drive circuit comprises photo coupler and relay, and the input of photo coupler is connected with the output of comparison circuit, and the output of photo coupler is connected with the input of relay, and the output of relay is connected with output interface.
Working procedure of the present invention is: knockout drum is arranged on centrifugal pump intake; When the liquid level in the knockout drum is lower than the height of setting, utilize sparger that the gas of gas-liquid separation tank top is extracted out, form vacuum; Its liquid level is risen, pump medium thereby remain to be full of in the centrifugal pump.The startup of sparger/stop is to be controlled by the liquid level of knockout drum, when the liquid level in the knockout drum reach a certain height, and the solenoid directional control valve switching-over, the halt system air feed, sparger quits work, and the diversion process finishes, and starts centrifugal pump; Along with the reduction of liquid level in the cabin, suction pressure also decreases, and moves closer to the pressure of medium vaporization; Part medium vaporization back enters into knockout drum and gathers the gas-liquid separation tank top along with pumping medium, and along with top air pressure increases, the liquid level in the knockout drum descends gradually; After liquid level dropped to certain altitude, the testing signal of liquid level sensor got into control circuit, after the hysteresis comparator conversion; Get into low-pass filter, compare with setting voltage value from voltage follower, the high-low level signal of output is isolated amplification rear driving solenoid directional control valve through photo coupler and relay; Solenoid directional control valve can commutate according to the testing signal of liquid level sensor, the start-up system air feed, and sparger is started working; Gas in the knockout drum is extracted out, its liquid level is risen.
Compared with prior art, advantage of the present invention is:
1, improved the automaticity of diversion process.The design of apparatus of the present invention mainly is that the working principle according to sparger has realized the diversion function; But with the maximum difference of existing technology is exactly design and the dynamo-electric design philosophy that combines through piping; Improved the automaticity of diversion process, through the liquid level sensor use that combines with solenoid directional control valve, as long as the low height of attending the meeting centrifugal pump suction ability being impacted of the liquid level in the knockout drum; Water diversion apparatus will start automatically; To keep high liquid level in the knockout drum, the knockout drum medium will be poured in down a chimney in centrifugal pump, and it is empty to avoid centrifugal pump to inhale.
2, stable, antijamming capability is strong.The present invention is provided with comparison circuit and drive circuit in controller; The major function of comparison circuit is in order to make the level sensing signal avoid being in critical unstable state at set point; Utilize the up and descending boundary of hysteresis comparator to comprise desirable set point; Increased between a liquid level watershed area, can effectively avoid the critical wild effect of circuit.The driving force that strengthens the high-low level signal is not only played in the setting of photo coupler in the drive circuit, but also has played the insulation blocking function of signal circuit and drive circuit effectively, has further strengthened the antijamming capability of circuit.
3, simple in structure, making and operating cost are low.Apparatus of the present invention can play the effect of automatic diversion; Can guarantee that again centrifugal pump can not produce cavitation phenomenons all the time in operation process, and simple in structure, stable; Making and maintenance cost are low, are specially adapted to the preceding diversion of startup of ballast for cruising pump, bilge pump and emergency fire pump.
Description of drawings
Fig. 1 is a workflow schematic representation of the present invention;
Fig. 2 is Fig. 1 middle controller circuit diagram.
Among the figure: centrifugal pump 1, knockout drum 2, liquid level sensor 3, controller 4, controller input interface 41, comparison circuit 42, hysteresis comparator 42a, low-pass filter 42b, voltage follower 42c, comparator 42d, drive circuit 43, photo coupler 43a, relay 43b, controller output interface 44, solenoid directional control valve 5, first pneumatic valve 6, second pneumatic valve 7, one way stop peturn valve 8, sparger 9, stop valve 10.
Embodiment
Below in conjunction with embodiment and embodiment the present invention is done further detailed explanation.
Referring to Fig. 1: a kind of centrifugal pump automatic water diversion device; Comprise centrifugal pump 1, knockout drum 2, liquid level sensor 3, controller 4, solenoid directional control valve 5, pneumatic valve 6 and 7, one way stop peturn valve 8, sparger 9 and stop valve 10; Knockout drum 2 is connected with centrifugal pump 1, liquid level sensor 3 and second pneumatic valve 7 respectively; The input of controller 4 is connected with liquid level sensor 3, and output is connected with solenoid directional control valve 5, and solenoid directional control valve 5 is connected with stop valve 10 with first pneumatic valve 6, second pneumatic valve 7; Sparger 9 is connected with second pneumatic valve 7, is connected with first pneumatic valve 6 through one way stop peturn valve 8 simultaneously.Specifically be the lower cavity of knockout drum 2 to be passed through pipeline be communicated with, be communicated with the water source through pipeline simultaneously with the suction port of centrifugal pump 1; The upper chamber of knockout drum 2 is communicated with the A mouth of second pneumatic valve 7 through pipeline; Liquid level sensor 3 is arranged on the middle and upper part of knockout drum 2.The output of liquid level sensor 3, promptly testing signal is connected with the input interface 41 of controller 4, and the output interface 44 of controller 4 is connected with the input of solenoid directional control valve 5.The A mouth of solenoid directional control valve 5 is connected with the pilot port P of first pneumatic valve 6 and second pneumatic valve 7 respectively; The A mouth of first pneumatic valve 6 is connected with the import of one way stop peturn valve 8; The outlet of one way stop peturn valve 8 is connected with the working gas imported L of sparger 9; The pumped gas import T of sparger 9 is connected with the B mouth of second pneumatic valve 7; The slop tank piping links to each other on the outlet D of sparger 9 and the ship, and gas is disposed in the dirty oil tank.The import of stop valve 10 is connected with source of the gas, and the outlet of stop valve 10 is connected with the B mouth of solenoid directional control valve 5 and the B mouth of first pneumatic valve 6 respectively.
Apparatus of the present invention are in the operation starting stage, and knockout drum 2 and pipeline are empty, according to the testing signal of liquid level sensor 3; When the actual liquid level value is lower than the liquid level of setting, solenoid directional control valve 5 is unlocked, and source of the gas is divided into two the tunnel after getting into through stop valve 10; The solenoid directional control valve 5 of leading up to is opened first pneumatic valve 6 and second pneumatic valve, 7, one road warp, first pneumatic valve 6 and the injection gas of one way stop peturn valve 8 as sparger 9 respectively, according to the basic principle of sparger 9; The gas that injection gas drives in ejection in the knockout drum 2 sprays through second pneumatic valve 7 in the lump; Thereby the water level in the knockout drum 2 is risen gradually, and when liquid level reach a certain height, solenoid directional control valve 5 cuts out; Source of the gas breaks off; First pneumatic valve 6 and second pneumatic valve 7 are closed under the effect of spring force thereupon, and sparger 9 quits work, and centrifugal pump 1 starts.
Referring to Fig. 2: automatic water diversion device middle controller 4 of the present invention is made up of input interface 41, comparison circuit 42, drive circuit 43 and output interface 44.The input of comparison circuit 42 is connected with input interface 41, and output is connected with the input of drive circuit 43, and the output of drive circuit 43 is connected with output interface 44.That is: the input of comparison circuit 42 is connected with the output of liquid level sensor 3 through input interface 41, and the output of comparison circuit 42 is connected with the input of drive circuit 43, and the output of drive circuit 43 is connected with the input of solenoid directional control valve 5 through output interface 44.
Claims (5)
1. centrifugal pump automatic water diversion device; Comprise centrifugal pump (1), knockout drum (2), liquid level sensor (3), controller (4), solenoid directional control valve (5), pneumatic valve (6,7), one way stop peturn valve (8), sparger (9) and stop valve (10); It is characterized in that: knockout drum (2) is connected with centrifugal pump (1), liquid level sensor (3) and second pneumatic valve (7); The input of controller (4) is connected with liquid level sensor (3); Output is connected with solenoid directional control valve (5); Solenoid directional control valve (5) is connected with first pneumatic valve (6), second pneumatic valve (7) and stop valve (10), and sparger (9) is connected with second pneumatic valve (7), is connected with first pneumatic valve (6) through one way stop peturn valve (8) simultaneously.
2. according to the said a kind of centrifugal pump automatic water diversion device of claim 1; The lower cavity that it is characterized in that said knockout drum (2) is communicated with the suction port of centrifugal pump (1) through pipeline; Upper chamber is communicated with second pneumatic valve (7) through pipeline, and liquid level sensor (3) is arranged on the middle and upper part of knockout drum (2).
3. according to the said a kind of centrifugal pump automatic water diversion device of claim 1; It is characterized in that said controller (4) is made up of input interface (41), comparison circuit (42), drive circuit (43) and output interface (44); The input of comparison circuit (42) is connected with input interface (41); The output of comparison circuit (42) is connected with the input of drive circuit (43), and the output of drive circuit (43) is connected with output interface (44).
4. according to the said a kind of centrifugal pump automatic water diversion device of claim 2; It is characterized in that said comparison circuit (42) comprises hysteresis comparator (42a), low-pass filter (42b), voltage follower (42c) and comparator (42d); The input of hysteresis comparator (42a) is connected with input interface (41); The output of hysteresis comparator (42a) is connected with the input of low-pass filter (42b); The output of the output of low-pass filter (42b), voltage follower (42c) is connected with the input of comparator (42d), and the output of comparator (42d) is connected with the input of drive circuit (43).
5. according to the said a kind of centrifugal pump automatic water diversion device of claim 2; It is characterized in that said drive circuit (43) comprises photo coupler (43a) and relay (43b); The input of photo coupler (43a) is connected with the output of comparison circuit (42); The output of photo coupler (43a) is connected with the input of relay (43b), and the output of relay (43b) is connected with output interface (44).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210110589.1A CN102644604B (en) | 2012-04-16 | 2012-04-16 | Automatic priming device for centrifugal pump |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210110589.1A CN102644604B (en) | 2012-04-16 | 2012-04-16 | Automatic priming device for centrifugal pump |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN102644604A true CN102644604A (en) | 2012-08-22 |
| CN102644604B CN102644604B (en) | 2014-08-13 |
Family
ID=46657635
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201210110589.1A Active CN102644604B (en) | 2012-04-16 | 2012-04-16 | Automatic priming device for centrifugal pump |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102644604B (en) |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103122862A (en) * | 2013-01-29 | 2013-05-29 | 武汉船用机械有限责任公司 | Liquid leakage monitoring device |
| CN103147993A (en) * | 2013-01-05 | 2013-06-12 | 浙江华球机械制造有限公司 | Mobile dual-purpose fire pump suitable for complex environment |
| CN103736227A (en) * | 2013-12-25 | 2014-04-23 | 广州中船黄埔造船有限公司 | Pressure-maintaining type firefighting system |
| CN105457203A (en) * | 2015-05-12 | 2016-04-06 | 新兴重工湖北三六一一机械有限公司 | Remote controlled and automatic sealed liquid sucking device |
| CN106812687A (en) * | 2016-12-27 | 2017-06-09 | 武汉船用机械有限责任公司 | A kind of gas extraction system for oil carrier ballast pump |
| CN114033713A (en) * | 2021-11-05 | 2022-02-11 | 扬州大学 | Pump station control method considering startup and shutdown loss based on orthogonal test-dynamic programming combined algorithm |
| CN114566943A (en) * | 2022-02-23 | 2022-05-31 | 睿士医疗科技(浙江)有限公司 | Overvoltage protection system of hardware |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH09137799A (en) * | 1995-11-15 | 1997-05-27 | Tlv Co Ltd | Ejector vacuum pump |
| CN1594887A (en) * | 2004-06-28 | 2005-03-16 | 龚寿奇 | Water self-priming apparatus for water pumps |
| JP2006161791A (en) * | 2004-12-10 | 2006-06-22 | Ebara Corp | Water level control device for plumbing tank |
| CN201513337U (en) * | 2009-09-02 | 2010-06-23 | 上海连成（集团）有限公司 | Novel vacuum automatic water drawing equipment |
-
2012
- 2012-04-16 CN CN201210110589.1A patent/CN102644604B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH09137799A (en) * | 1995-11-15 | 1997-05-27 | Tlv Co Ltd | Ejector vacuum pump |
| CN1594887A (en) * | 2004-06-28 | 2005-03-16 | 龚寿奇 | Water self-priming apparatus for water pumps |
| JP2006161791A (en) * | 2004-12-10 | 2006-06-22 | Ebara Corp | Water level control device for plumbing tank |
| CN201513337U (en) * | 2009-09-02 | 2010-06-23 | 上海连成（集团）有限公司 | Novel vacuum automatic water drawing equipment |
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103147993A (en) * | 2013-01-05 | 2013-06-12 | 浙江华球机械制造有限公司 | Mobile dual-purpose fire pump suitable for complex environment |
| CN103147993B (en) * | 2013-01-05 | 2015-09-16 | 浙江华球机械制造有限公司 | Be suitable for the dual-purpose fire water pump of complex environment downward moving |
| CN103122862A (en) * | 2013-01-29 | 2013-05-29 | 武汉船用机械有限责任公司 | Liquid leakage monitoring device |
| CN103736227A (en) * | 2013-12-25 | 2014-04-23 | 广州中船黄埔造船有限公司 | Pressure-maintaining type firefighting system |
| CN105457203A (en) * | 2015-05-12 | 2016-04-06 | 新兴重工湖北三六一一机械有限公司 | Remote controlled and automatic sealed liquid sucking device |
| CN105457203B (en) * | 2015-05-12 | 2018-07-27 | 新兴重工湖北三六一一机械有限公司 | A kind of self-styled liquid suction device of remote control |
| CN106812687A (en) * | 2016-12-27 | 2017-06-09 | 武汉船用机械有限责任公司 | A kind of gas extraction system for oil carrier ballast pump |
| CN106812687B (en) * | 2016-12-27 | 2018-09-18 | 武汉船用机械有限责任公司 | A kind of exhaust system for oil carrier ballast pump |
| CN114033713A (en) * | 2021-11-05 | 2022-02-11 | 扬州大学 | Pump station control method considering startup and shutdown loss based on orthogonal test-dynamic programming combined algorithm |
| CN114033713B (en) * | 2021-11-05 | 2023-10-31 | 扬州大学 | Pump station control method considering start-stop loss based on orthogonal test-dynamic programming combination algorithm |
| CN114566943A (en) * | 2022-02-23 | 2022-05-31 | 睿士医疗科技(浙江)有限公司 | Overvoltage protection system of hardware |
Also Published As
| Publication number | Publication date |
|---|---|
| CN102644604B (en) | 2014-08-13 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102644604B (en) | Automatic priming device for centrifugal pump | |
| US11298651B2 (en) | Gas-liquid separator for separating at least one liquid component from a gaseous component | |
| CN102840140B (en) | Starting method of outer ring type efficient starting system for self-priming pump | |
| CN203879753U (en) | Self-suction device for jet flow out of centrifugal pump | |
| CN201288937Y (en) | Self-control type centrifugal pump vacuum priming device | |
| CN201461456U (en) | Double-suction submersible electric pump | |
| CN105952612B (en) | A kind of pump self-priming apparatus and method | |
| WO2010057413A1 (en) | Automatic-control fluid jet guide lift pump | |
| CN110409589B (en) | Non-pump station anti-blocking jet flow vacuum drainage system | |
| CN101101000A (en) | Automatic control turbine synchronous discharging-suction pump | |
| CN201687726U (en) | Synchronous self-priming pump | |
| CN208518908U (en) | A kind of fully automatic vacuum auxiliary diesel vacuum aided self priming pump | |
| CN212928228U (en) | Water pump is from inhaling system based on control | |
| EP3064655A1 (en) | Train water supply apparatus and control method therefor | |
| CN205401153U (en) | Self -suction type centrifugal pump | |
| CN204663903U (en) | A kind of jet pump device | |
| CN102287171A (en) | Automatic delivery device for natural gas well foam water discharge rod | |
| CN203613638U (en) | Vacuum drainage-type sewage suction collection system | |
| CN203834571U (en) | Automatic exhaust device for ship water supply system | |
| CN106640680A (en) | Electric self-suction fire pump | |
| CN105673514A (en) | Self-priming centrifugal pump | |
| CN110685923A (en) | Composite strong self-suction centrifugal pump set | |
| CN2929264Y (en) | Self control turbine synchronous discharge and sucking pump | |
| CN201546971U (en) | Efficient suction and drain pump | |
| CN2453047Y (en) | Dual control and air compensation type automatic water supply equipment |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant |