This paper mainly introduces the development history, classification, working principle and related applications of pumps commonly used in life, and boldly looks forward to the development direction of pumps.

Key words: development history, classification, principle, application and direction.

Introduction: A pump is a machine for conveying or pressurizing liquid. It transfers the mechanical energy or other external energy of the prime mover to the liquid, which increases the energy of the liquid. Pumps are mainly used to transport liquids, including water, oil, acid-base liquids, emulsions, suspension emulsions and liquid metals. They can also transport liquids, gas mixtures and liquids containing suspended solids. In daily life and industrial production, we can't live without pumps.

Development history of pumps

The improvement of water is very important for human life and production. In ancient times, there have been various water lifting appliances, such as Egyptian chain pump (BC 1 7th century), China orange (BC17th century), windmill (BC1/century) and waterwheel (AD1century). More famous is the screw invented by Archimedes in the third century BC, which can lift water to several meters steadily and continuously, and its principle is still used by modern screw pumps.

Around 200 BC, the fire pump invented by the ancient Greek craftsman Ketcibius is the most primitive piston pump, which has the main components of a typical piston pump, but the piston pump developed rapidly after the steam engine appeared.

1840- 1850, worthington invented the piston pump with the pump cylinder and steam cylinder opposite, which marked the formation of modern piston pump. 19th century is the climax of the development of piston pump, which was used in hydraulic press and other machinery. However, with the rapid increase of water demand, since the 1920s, the low-speed piston pump with greatly limited flow rate has been gradually replaced by the high-speed centrifugal pump and rotor pump. However, in the field of high pressure and small flow, reciprocating pumps still occupy the main position, especially diaphragm pumps and piston pumps, which have unique advantages and are used more and more.

The appearance of rotor pump is related to the increasingly diversified requirements of liquid transportation in industry. As early as 1588, a four-leaf vane pump was recorded, and other kinds of rotor pumps appeared one after another, but until 19 century, rotor pumps still had some shortcomings such as large leakage, large wear and low efficiency. At the beginning of the 20th century, people solved the problem of rotor lubrication and sealing, and adopted high-speed motor to drive rotor pump, which is suitable for high pressure, small and medium flow and various viscous liquids. The type of rotary pump and the type of liquid suitable for transportation are beyond the reach of other pumps.

The idea of using centrifugal force to deliver water first appeared in Leonardo? In Leonardo da Vinci's sketches. 1689, French physicist Papan invented a four-blade volute centrifugal pump. But what is closer to the modern centrifugal pump is the so-called Massachusetts pump with radial straight blades, semi-open double suction impeller and volute, which appeared in the United States 18 18. From 185 1 to 1875, multistage centrifugal pumps with guide vanes were invented one after another, which made it possible to develop high-lift centrifugal pumps.

Although as early as 1754, the Swiss mathematician Euler put forward the basic equation of impeller hydraulic machinery, which laid a theoretical foundation for the design of centrifugal pump, it was not until the end of 19 that the invention of high-speed motor made the centrifugal pump obtain an ideal power source and its advantages were fully exerted. Based on the theoretical research and practice of many scholars, such as Renault in Britain and Pfleidrell in Germany, the efficiency of centrifugal pump has been greatly improved, and its performance range and application field have been expanding day by day, making it the most widely used and the largest output pump in modern times.

Classification of pumps

Pumps are usually divided into positive displacement pumps, power pumps and other types of pumps according to their working principles, such as jet pumps, water hammer pumps, electromagnetic pumps and gas lift pumps. Besides the working principle, pumps can be classified and named in other ways. For example, according to the driving mode, it can be divided into electric pump and hydraulic pump; According to the structure, it can be divided into single-stage pump and multi-stage pump; According to the purpose, it can be divided into boiler feed pump and metering pump; According to the nature of the transported liquid, it can be divided into water pump, oil pump and mud pump.

Working principle of pump

3. 1 positive displacement pump

The flow rate of positive displacement pump is constant at a certain speed or reciprocating times, and hardly changes with pressure; The flow and pressure of reciprocating pump fluctuate greatly, so corresponding measures should be taken to reduce the fluctuation; Rotary pumps generally have no pulsation or only a small pulsation; Self-suction ability, which can pump out the air in the pipeline and suck in the liquid after the pump is started; When starting the pump, the valve of the discharge pipeline must be fully opened; Reciprocating pump is suitable for high pressure and small flow; Rotor pump is suitable for small and medium flow and high pressure; Reciprocating pump is suitable for conveying clean liquid or gas-liquid mixture. Generally speaking, the efficiency of positive displacement pump is higher than that of power pump. The power pump transfers mechanical energy to the liquid through the action of the rapidly rotating impeller, so that its kinetic energy and pressure energy are increased, and then most of the kinetic energy is converted into pressure energy through the pump barrel to realize transportation. Power pump is also called impeller pump or vane pump. Centrifugal pump is the most common power pump.

3.2 Power pump

The lift generated by the power pump at a certain speed has a limited value, and the lift changes with the flow rate; Stable operation, continuous transportation, no pulsation of flow and pressure; Generally, there is no self-priming ability, and it is necessary to fill the pump with liquid or vacuum the pipeline before it can start working; Wide range of applicable performance; Suitable for conveying clean liquid with low viscosity. Specially designed pump can convey mud, sewage, etc. Or water. Power pumps are mainly used for water supply, drainage, irrigation, process liquid transportation, power station energy storage, hydraulic transmission and ship jet propulsion.

3.3 Others

Other types of pumps refer to pumps that transfer energy in other ways. For example, the jet pump sucks the fluid to be transported into the pump by relying on the working fluid ejected at high speed, and transfers energy by mixing the two fluids for momentum exchange; Water hammer pump uses the energy generated when running water brakes suddenly to make part of the water pressure rise to a certain height; Electromagnetic pump makes charged liquid metal flow under the action of electromagnetic force to realize transportation; The air lift pump sends compressed air or other compressed gas to the bottom of the liquid through a conduit to form a gas-liquid mixed fluid lighter than the liquid, and then presses the mixed fluid upward by using the pressure of the liquid outside the pipe.

4. Application of pump in production and life

4. 1 application of stainless steel stamping centrifugal pump in water system

Stainless steel stamping centrifugal pump, hydraulic valve check valve pump station, is mainly used for small-flow and high-lift water systems, such as drinking water supply system, pressure boiler water supply system, high-purity water purification system, as well as washing and spraying processes in medicine, food, fine chemicals, paper making and other industries. The energy-saving information dissemination center of the State Economic and Trade Commission recently listed the stainless steel stamping centrifugal pump as the "best energy-saving practice case", and analyzed the application and benefits of the equipment.

It is understood that the traditional casting pump is manufactured by complex processes such as mold making, mold filling and machining, which consumes a lot of electricity and materials, has a high labor intensity, seriously pollutes the environment, and cannot cast a small-flow impeller with a narrow outlet width. Stainless steel stamping centrifugal pump is manufactured by stamping welding process, which replaces the traditional casting process. The production of pump body can save more than 70% materials, improve the efficiency by 3%-5%, easily realize mechanized and automatic batch production, reduce environmental pollution and reduce labor intensity.

The manufacturer of stamping centrifugal pumps produces 2082 sets of stainless steel stamping centrifugal pumps. Compared with the traditional process, the new process saves 3.47 tons of stainless steel material and reduces the power consumption of casting by 7634 kWh. For users of bottle washing and filling machines, the actual running power of the water pump has also dropped from 2. 18kW to 2. 1 1kW, and each machine saves 3.2% electricity.

In addition, due to light weight, small volume, reasonable overall structure and convenient maintenance, the maintenance cost is also reduced. According to the statistics of the National Bureau of Statistics and China Machinery Industry Federation, the annual demand for casting pumps in China is 4.57 million, and the annual demand for alloy casting small-flow pumps is more than 380,000. Stainless steel stamping centrifugal pump is lighter and more beautiful than casting pump, with high efficiency and low price, which is half of that of imported pump. Remarkable economic benefit, wide application range and broad market prospect.

4.2 Principle and application example of hydraulic water hammer pump

4.2. 1 Working principle and water lifting performance of hydraulic water hammer pump

Hydraulic water hammer pump automatic water supply equipment is a hydraulic energy upgrading and conversion device designed and manufactured by using hydraulic impact principle and hydraulic transmission principle. The main equipment consists of three parts: pulse generator, energy coupler and accumulator. It is the main equipment of a new micro-hydraulic station. This kind of hydraulic pump is essentially a special reciprocating pump or pump group, which uses the transmission characteristics of hydraulic energy to form a special type of variable displacement hydraulic machinery as a whole.

In the hydraulic system, for some reason, the liquid pressure suddenly rises, resulting in a high pressure peak, which is called hydraulic shock. The peak pressure of hydraulic impact is often many times higher than normal pressure. Water hammer pump uses the principle of hydraulic impact, that is, when water suddenly closes the outlet valve during normal flow, it will have a great impact in the pump body. With this impact, water can be sent to a very high place. The hydraulic impact is unsteady flow, and the pressure wave propagates back and forth along the inlet power pipeline (long water diversion pipe) at speed C. In the design of water hammer pump, the maximum increment Δ p of pipeline pressure after the valve is suddenly closed is generally used as the pumping power of the pump. Because hydraulic shock is a decay process, the first wave of pressure rise is studied when it reaches the entrance of the pipeline.

Assuming that the cross-sectional area of the pipeline is a, the length of the pipeline is l, the initial velocity of the liquid in the pipeline is v, the liquid density is ρ, and the time for the pressure wave to propagate from the drainage impact valve to the inlet of the upstream water supply pool is t, then the momentum equation is applied:

δP？ Answer? T=ρALV

So δ p = ρ LV/t =ρv.

Where C=L/T is the propagation speed of pressure wave in water, and c =1400 m/s.

You can calculate the maximum rising pressure Δ p caused by the sudden closure of the drainage impact valve after water enters the water hammer pump from a height of 2m through a long water diversion pipe, and calculate the initial velocity v of water flow according to the law of conservation of energy:

mgh=mV？ V/2，

Then v = (2gh) 0.5 = (2 * 9.8 * 2) 0.5 ≈ 6.3m/s.

Therefore, when the impact valve suddenly closes, the maximum rising pressure Δ p is:

δP = cρV = 1400 * 1000 * 6.3 = 8.8 MPa

Then calculate the pressure p required to lift the water 100 m:

p =ρGH = 1000 * 9.8 * 100 = 0.98 MPa

It can be seen that Δ p is much larger than p, so in theory, it is not a problem to use water hammer pump to raise part of the water volume of 2 m head flow to the height of 100 m.

Simply put, the pump device consists of a pump chamber, a pump seat and an accumulator. There are two valves in the pump house: one is the drainage impact valve W, and the other is the water delivery valve D. The two valves form a combined automatic valve. The combined automatic valve automatically opens and closes under the action of head water flow, generating hydraulic pulse: the water pumped from the water inlet pipe enters the impact valve W and is discharged. When the discharge speed reaches the design value, the impact valve W suddenly closes, thus generating a boost wave. Under this high pressure, the water delivery valve D is opened, and a part of the moving water flows into the air tank, and then flows from the air tank to the use point or the high-level reservoir. The mass flow of the water inlet pipe can be exhausted by water delivery, which makes the water stop temporarily. At this time, the pressure wave decays, and due to the pressure difference between the upper and lower parts, the water delivery valve D automatically closes. Due to the elasticity of the water inlet pipeline and water column, after the impact of water lifting is weakened, the water column swings back slightly along the flow direction, so there is negative pressure in the pump casing, which urges the impact valve W to open itself. Open the impact valve W to continue to drain water, and then repeat the above process to extract water. In order to obtain continuous and uniform water flow, a water collector, also known as a collector, is installed on the water conveying side. Therefore, the water hammer pump is structurally composed of two core components: the accumulator and the combined automatic valve.

The most important reciprocating parts in pump structure are the structure and characteristics of impact valve and water delivery valve. The working performance of the pump can be improved by improving the automatic valve. The water hammer pump works without control, so the actions of all parts are required to be timely, accurate, safe and reliable.

According to the data, it is best to open and close the impact valve of water hammer pump at least 40 times/minute. It can be seen from the working process of water hammer pump that it is very important to design and manufacture a combination valve that can automatically open and close and react quickly in order to make the pump work normally.

The hydraulic impact formula of water hammer pump is: △P=CρV=LV/t, where △P is the impact pressure; L is the propagation distance of shock wave; V is the average velocity in the water pipe before impact; T is the closing time of the impact valve. It can be seen from the formula that in order to improve the pressure of hydraulic impact, it is necessary to increase the average velocity V in the water pipe before impact, shorten the closing time T of the impact valve and increase the propagation distance L of the shock wave. On the premise that the water hammer pumping station has been built (H, L and V are fixed), it is mainly to reduce the closing time t of the impact valve in order to produce obvious hydraulic impact and give consideration to the efficiency of the pumping station.

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The combined automatic valve of water hammer pump is two special valves, and its working power is only the pulse power of water flow and its own weight. From the mechanical analysis of the automatic valve, it can be seen that the closing time of the impact valve mainly depends on whether there is a speed-increasing mechanism, the elasticity of the gasket, the weight of the valve disc, the flow rate at the outlet and other factors. The opening time of the impact valve mainly depends on the negative pressure in the pump shell, the resilience of the gasket, the weight of the valve disc and the flow rate of the water outlet.

The automatic impact valve of hydraulic water hammer pump developed by Wuhan Runze Water Conservancy Technology Center can be opened and closed by itself without bearing in structure, so as to prevent the valve stem from wearing. In addition, in order to prevent the impact and vibration generated when the impact valve is closed, the buffer structure is adopted in the structure, so the impact force in the pump shell, the stress of the water inlet pipe connected to the pump and the impact force acting on the foundation are very small. In the research and development, the characteristic method is used to analyze the hydraulic impact and flexible water hammer by computer, and a comprehensive experimental study and theoretical analysis are carried out from the aspects of materials and strength. Through the reasonable design of hydraulic energy transfer characteristics, the hydraulic water hammer pump increases the energy flow density, accurately designs the pulse pumping function of the hydraulic shock wave of the pulse generating component, accelerates the loading of the hydraulic water hammer pump, and enables the pulse generating component to automatically impact the valve (including the auxiliary speed-increasing valve disc device) to reach the switching frequency of 30-300 times per minute, thus realizing the medium-high frequency operation.

The falling water flows out from the intake pool (pump station water supply pool) with a height of 1 to 7 meters, and then enters the base to fill the pump house through the long water diversion pipe until it reaches the water level of the intake pool, at which time the automatic valve is closed. In order to start the water hammer pump, it is necessary to open the impact valve W several times by hand to further increase the pressure head of the air chamber in the accumulator. When the pressure in the air chamber reaches about 3 times of the drop, the pressure generated by the water column swing of the water inlet pipe is enough to make the output valve open by itself and make the water hammer pump act. At this time, the pressure head of the air chamber increases continuously until it reaches the pressure head value at the top of the water pipe outlet, and then the pressure head is basically stable. When the water head and pressure head are high, the air in the air chamber of the general accumulator is gradually absorbed by high-pressure water, which makes the air chamber eventually fail and the pressure peak value keeps rising, which will cause mechanical accidents. Therefore, in the application of high lift, it is necessary to redesign the hydraulic accumulator assembly of water hammer pump, mainly using airbag accumulator, or taking measures to manually or automatically replenish air to the air storage tank.

The head and flow rate of drip source are one of the important factors that determine the head and pumping capacity of pump. In addition, the working performance of the pump is also affected by the installation angle of the diversion pipe, the caliber and length of the diversion pipe and the riser, and the number of times the impact valve is opened and closed. After many engineering tests and field installation and application tests, the following empirical formulas are obtained:

(1) the relationship between the lift h and the flow head h: h/h =10-50;

② The hydraulic water hammer pump is regarded as the combination of power machine and water pump, and its efficiency can be defined by the following formula:

η=qh/(QH)

η is the pump efficiency; Q is the pumping flow; H is the lifting height; Q is the water inflow of the water inlet pipe; H is the drop.

Empirical formula of pump efficiency:

1、η=( 1. 17- 1.37)-0.2((H-H)/H)0.5

(h-H)/H=3- 17 (using various gas tanks as hydraulic accumulators)

2.90%≥η≥60%, (h-h)/h = 2 ~ 49 (hydraulic accumulator adopts diaphragm accumulator).

③ Pumping capacity of water hammer pump Q: Q = η hq/(h-h+η h)

④ length of draft tube L: L = 7- 12h (the value varies with the drop).

⑤ Installation angle α of draft tube: elevation angle should be greater than 5 and less than 20, and 7-15 is the best installation angle.

⑥. Diameter of diversion pipe D: D = 0.3 (60Q) 0.5 (Q is the perennial guaranteed flow of water source into the pump).

⑦. Diameter of riser d: d=0.5-0. 1D (this value varies with the drop ratio h/H). The main technical indexes of water hammer pump performance are its power and efficiency. However, due to the limitation of installation site, terrain and water source, various factors should be considered comprehensively in the design, such as water supply, head, length of water inlet pipe, lifting height and lifting flow.

According to the data, the longest working life of water hammer pump abroad can reach more than 100 years, and its wearing parts are only rubber pads, seals and bolts.

4.2.2 Advantages of using hydraulic water hammer pump

1. The hydraulic water hammer pump increases the energy flow density through the reasonable design of hydraulic energy transfer characteristics, accurately designs the pulse pumping function of the hydraulic shock wave of the pulse generating component, speeds up the loading of the hydraulic water hammer pump, and enables the pulse generating component to automatically impact the valve (including the auxiliary speed-increasing valve disc device) to reach the switching frequency of 30-300 times per minute, thus realizing medium-high frequency operation.

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According to the data, the switching frequency of automatic impact valve of water hammer pump is preferably not less than 40 times per minute. Engineering application data show that domestic similar products generally run at a low frequency (only 20-40 times per minute, no more than 60 times).

2. Low operation noise. The operating noise of the new RZ-50 hydraulic water hammer pump for drinking water is less than 80 decibels, and the operating noise of similar domestic new products (such as BIL series water hammer pump imported from Germany) is as high as 105- 130 decibels.

3. "Hydraulic water hammer pump" uses stainless steel and other corrosion-resistant materials to make the accumulator cylinder, so as to avoid the corrosion pollution of the lifting water flow of the water hammer pump micro-hydraulic station.

4. The effective volume of hydraulic accumulator can be effectively guaranteed by simple measures such as (including manual) inflation device, especially the volume of air chamber and energy storage will not be lost in long-term operation; The air supply of the hydraulic accumulator does not need to be emptied, which will not cause the water hammer pump to stop. Domestic similar products (such as BIL series water hammer pumps imported from Germany) mostly use semi-accumulator (accumulator without gas preloading measures), which will cause the water hammer pump to stop when exhausting and supplementing air.

5. The hydraulic accumulator assembly adopts the isothermal loading cycle working mode, which reduces the heat loss of the air chamber of the hydraulic accumulator that may be caused by the automatic impact of the pulse generating assembly on the valve in the middle and high frequency rapid loading work, cancels the polypropylene sleeve insulator on the inner surface of the cylinder of the traditional water hammer eliminator (air bag accumulator, which adopts the adiabatic loading cycle working mode), and reduces the processing difficulty and manufacturing cost.

6. "Hydraulic water hammer pump", the full name is "modular compound hydraulic transmission water hammer pump", which consists of three parts: pulse generating part, energy coupling part and energy storage part. Hydraulic water hammer pump uses energy coupling element as a special energy converter to realize energy coupling, which can realize the conversion of DC/ AC hydraulic working mode. Automatic water supply equipment of hydraulic water hammer pump-New RZ series hydraulic water hammer pump for drinking water is a hydraulic energy upgrading and conversion device designed and manufactured by using hydraulic impact principle and hydraulic transmission principle. Therefore, the design principle of hydraulic water hammer pump is different from the traditional water hammer pump which only adopts the water hammer principle.

5. Development trend of pumps

The technical development of pumps, like the development of other industries, is driven by market demand. Nowadays, history has entered 2 1 century. Under the background of high-tech development in environmental protection, electronics and other fields and huge demand for sustainable development in the world, people have brought rapid technological changes and development to many industries or fields, including the pump industry.

The technical development trend of pumps mainly includes the following directions:

(1) product diversification

The vitality of products lies in market demand. Today's market demand is to have its own characteristics and be different; It is this that creates the diversification trend of pump products. Its diversity is mainly reflected in the diversity of pump conveying media, the difference of product structure and the difference of operation requirements.

Judging from the diversity of conveying media, the earliest pumps can convey single water and other flowable liquids, gases or mud, and now they can convey solid-liquid mixtures, gas-liquid mixtures and solid-liquid-gas mixtures until they can convey living things such as potatoes and fish. Different conveying objects have different requirements for the internal structure of the pump.

In addition to the different requirements of the conveying object on the pump structure, new requirements are put forward for the internal or external structure of the pump from the aspects of installation form, pipeline layout form and maintenance. At the same time, various manufacturers have also added their own ideas in structural design, further improving the diversification of pump structure.

Based on the overall background of sustainable development and environmental protection, the operating environment of the pump puts forward many requirements for the design of the pump, such as reducing leakage, reducing noise and vibration, improving reliability and prolonging life. , which put forward different key points or several key points in parallel, will inevitably form a diversified pump form.

(2) The organic combination of pump design level improvement and manufacturing technology optimization.

In the information age, pump designers have already used computer technology to develop and design products (such as the use of CAD), which greatly improves the speed of design itself and shortens the product design cycle. In the production-oriented manufacturing industry, the manufacturing technology represented by numerical control technology CAM has penetrated into the production of pumps. However, from the current domestic situation, the numerical control technology CAM is mainly used for the production of mass products. For single-piece or small-batch production, CAM technology has not been widely implemented in the pump industry at present, and single-piece and small-batch production is still mainly based on traditional production equipment.

Because the market requires manufacturers to shorten the delivery time as much as possible, especially for special products (products produced according to users' requirements), pump manufacturers are inevitably required to accelerate the use of CAM technology, even computer integrated manufacturing system (CIMS) and flexible manufacturing (FMC and FMS), and deal with all links from design to manufacturing molds and parts processing in a coordinated manner, so as to ensure that once the design is completed, the processing of product parts tends to be completed at the same time, thus ensuring that the production cycle of products is shortened.

At the same time, in addition to computer drawing, the strength analysis, reliability prediction and three-dimensional design of products will be realized on the computer carrier, and the technical problems, local structural problems and assembly problems that need to be found and solved in production will be well prevented before production, thus shortening the trial production cycle of products.

(3) Standardization and modularization of products

At the same time of product diversification, as a general product, the total amount of pumps is still huge. In the market, besides technical competition, the price competition of products, especially general products, is an inevitable trend. Under the trend of product diversification, it is necessary to realize the competitive advantage of product price, improve the standardization degree of product parts and realize the modularization of product parts. After many parts are modularized, products can be diversified by combining different modules or changing the characteristics of a single part. At the same time, only by improving the standardization of parts, it is possible to truly realize the scale of parts production based on product diversification, thus reducing production costs and forming competitive advantages of products, and it is also possible to further shorten the product delivery cycle based on product diversification.

(4) Improve the internal characteristics of the pump and pursue the external characteristics.

The inherent characteristics of the pump refer to the inherent characteristics of the product, including product performance, parts quality, assembly quality of the whole machine, appearance quality and so on. Or simply quality. At this point, many pump manufacturers are concerned about this and strive to improve it. In fact, we can find that many products can't achieve the effect of ex-factory inspection after they are tested and delivered to users, and there are some problems such as overload, increased noise, unsatisfactory use or reduced service life. In practice, the working point or characteristic of the pump is called the external characteristic or system characteristic of the pump.

When designing a product, technicians often spend a lot of time on improving the efficiency of a product by one percent. However, if the operation of the pump deviates from the designed high efficiency point, the actual operation efficiency will be reduced by more than 1%. At present, pump manufacturers provide users with control equipment and complete sets of equipment including frequency conversion, which actually involves the pursuit of external characteristics of pumps. On this basis, we should pay more attention to the centralized control system of the pump, and improve the operation efficiency of the whole pump and pumping station through a higher level, which is the pursuit of the external characteristics of the pump.

From the point of view of sales, selling products is the inherent characteristics of selling pumps; Paying attention to the external characteristics of pumps means that manufacturers not only sell products, but also sell pumping stations (complete sets of projects).

From the use point of view, a good product must be a product suitable for the use environment, not a product that has been tested and judged by the factory.

(5) Further development of mechatronics.

Just like the development of science and technology, there are more and more interdisciplinary and marginal disciplines in the field of science and technology at this stage, and the research of interdisciplinary is very common, as is the technical development of pump products. Taking the shielded pump as an example, it is impossible to cancel the shaft seal of the pump only because of the motor structure. To solve the noise problem of pump, we should not only solve the flow pattern and vibration of pump, but also solve the noise of motor blades and electromagnetic field. In order to improve the reliability of submersible pump, measures such as leakage protection and overload protection must be added to submersible motor. To improve the operation efficiency of water pump, we must rely on the application of control technology. All these show that to develop the technical level of pumps, we must start from the aspects of supporting motors and control technologies at the same time, and comprehensively consider them to maximize the comprehensive level of electromechanical integration.

refer to

[1] Liu Yun, edited by Jiang Peizheng, process fluid machinery. Beijing Chemical Industry Press 2009

[2] Sun Qicai, edited by Jin Dingwu, principle, structure and design calculation of centrifuge. Beijing: Machinery Industry Press, 1987.

[3] Guan, editor-in-chief, Handbook of Modern Pump Technology, Beijing: Aerospace Press, 1995.