Submersible multistage pumps type on. Single and multistage centrifugal pumps

garden equipment 15.06.2019

garden equipment

The use of surface pumps is associated with expansion individual building. The issue of water supply is more reliably solved with the use of surface stations for water.

How to choose a surface pump

Depth of liquid rise. This indicator determines the fundamental possibility of using the device. The distance from the surface of the water mirror to the suction pipe is measured.
Developed pressure. The indicator indicates the allowable range of liquid transmission. It is required to take into account the length of the pipes of the irrigation or water supply system.
Engine power. Indirectly affects the two named indicators.
As the power increases, the lifting depth and pressure increase. It is not always worth trusting models that, with modest motor values in kW, promise excellent performance.

Don't forget about power consumption as well.

Manufacturing material. High-quality components (blades, bearings) will save on operation and will withstand stressful working conditions.
Noise at work. This indicator is not taken into account only with the possible isolation of the working structure.
Safety. The group includes such design features as tightness, ease of carrying out installation work, build quality.
Service maintenance. The absence of a service center in the region creates certain difficulties with the purchase of spare parts and warranty repairs. It is not always possible to buy parts from the seller.

When choosing a model great influence will not have such factors:

Brand name. It is not necessary to overpay for a well-known name. Several well-known brands stand out in the segment, but new companies have proven themselves well.

Along with the well-known Pedrollo model, Ombigena models and domestic pumps are actively sold.

Price. The choice of the unit is made according to the balance of characteristics.
Automatic assistants. If it is possible to periodically monitor the operation of the device, the need to overpay is not always justified.

Pros and cons

The surface unit is designed to lift water from an open source. An additional area of \u200b\u200buse is considered pumping water from basements and pits during construction work.

Among the characteristics of a surface pump, the height of the water rise is distinguished. This indicator is at the level of 7-8 meters, depending on the design.

The lifting height is determined taking into account the horizontal-vertical proportion. The optimal ratio is the proportion when water is diverted to a distance of up to 4 meters per meter of lift.

When buying a pump, pay attention to the pressure generated. This indicator depends on the design, efficiency and installed power.

simplicity of design;
ease of installation work;
high generated pressure;
small overall dimensions;
high reliability combined with durability;
electrical safety;
work with a small water reservoir.

sensitivity to pumping contaminated water;
small depth of immersion;
high noise level.

Pumps of individual designs require filling the suction line with water to start working.

The versatile Pedrollo CKm 50 combines 35 meters of head and 9 meters of lift. In this case, the pump works with slightly contaminated liquids.
The productive model NCS 12-10 is capable of pumping up to 12 m 3 /hour, and starts working without liquid in the body.
The Wilo PB-201 EA model combines indicators by position: head 35 m, pumping volume - 2 m 3 / hour, affordable price.

The best automatic surface pumps

Reliable model Speroni KPM 50 differs in use of strong durable details, is silent in work.
productive unit RSM 5GA company of the same name. The pump is intended for regulation of internal pressure, productive.
Model Marina KPM 50 very economical.

Automatic watering is required for autonomous water supply and irrigation systems. Proper operation of the machine and control programs ensures a good end result.

A feature of the work is the interaction with automatic devices. These kits contain:

control units;
valves;
branched pipelines;
irrigation equipment.

The task of the pump is an uninterrupted supply of water when the device is turned on autonomously and replenishment of supplies to the desired level.

When choosing the type of unit, the following characteristics are taken into account:

Volume of pumped water. Calculated based on the number of consumers. For example, autonomous watering will require less water than with additional supply to the water supply system at home.
The quality of the pumped liquid. This characteristic depends on the type of water source, the degree of pollution.
lift height. This indicator varies from 5 to 10 meters.
Developed pressure. This characteristic ensures the range of water delivery, affects the fineness of the liquid spray.

In practice, the designs of devices of two types are used - piston and centrifugal.

provide high pressure at a constant flow;
equally effective over long periods of time.

Piston-type models are overall larger in comparison with vane designs and are demanding on the quality of the pumped liquid. When working, breaks are required at relatively short time intervals.

The performance of this type depends on the functioning of the "start-stop" system.

The best household surface pumps

Model Aquario ARM-100, which at minimum specifications is economical and durable.
productive unit Gilex Jumbo with an index of 60/35 H-K, which, with a consumption of 600 W, provides a pressure of up to 35 meters.
German model Wilo PB-088EA consumes 140 W in one hour, but provides a pressure of 9 meters.

A feature of the devices is efficiency in comparison with lifting stations for industrial use.

Two types of models are used:

centrifugal models of a single-stage type;
centrifugal pumps with several steps.

The design is chosen taking into account the scope and performance.

Compact drive. This principle ensures a compact and low noise design.
Water consumption. For household pumps, the maximum value is 70 l / min.
The maximum fluid pressure is 1.7 atmospheres (or 17 meters).
The minimum power consumption is from 500 watts.

long work without interruption;
ease of installation work;
affordable price offer;
small dimensions.

suction height ranges from 7-9 meters;
pumping range - from 17 to 42 meters.

Best surface pumps for dirty water

powerful model Pedrollo D20. Productivity is 20 m 3 /hour. Head height 27 m.
Universal Model Grunfos Unilift CC 9 A1. Copes with a volume of 14 m 3 / hour. Head height 9 m.
budget model Grunfos Unilift CC 5 A1. Productivity is 6 m 3 /hour. Head height 5 m.

Most often pumps are used in cases:

drainage basements and pits;
pumping out muddy water from cellars, sewer cellars during floods and natural disasters;
drainage of fountains, artificial reservoirs and channels;
pumping fluid from drainage well or a sump for processing garden plantings.

All models are self-priming.
The size of the particles polluting the liquid is limited by installing a filter, and is in the range of 10-15 mm.
Wide operating temperature range - from -10˚С to +90˚С.

When choosing a model, the conditions for future operation are taken into account.

The advantages of the pumping device are related to the design:

Screw pumps cope with sludge masses regardless of their density.
Membrane models work with large inclusions (up to 50 mm) at a concentration of such particles of no more than 50%.

Depending on the version, the devices are driven by electric or petrol.

noise at work;
the need for proper placement of suction hoses;
lift height limitation.

The best surface fecal pumps

Universal representative - Grundfos Liftaway B passes up to 100 l/min, temperature range from 50 to 70°C.
Powerful Representative Wilo DrainLift Box It has throughput 300 l / min and power not more than 600 watts.
Productive pump for cold drains DAB Fecalift 200 capable of pumping up to 70 l / min, motor power up to 65 watts.

A variety of a group of devices for pumping dirty water are faecal stations. They differ from simpler models:

powerful engine;
the presence of a grinding device or filter element;
equipped with float switches.

Models have limitations in use for a number of indicators:

low suction height - from 1 m;
inefficient operation of the pump at low power;
frequent breakdowns due to high load.

When choosing a model, consider:

the presence of the function of setting the pressure to start and stop the operation of the pump;
compliance with the supply and pressure capabilities of the installed equipment.

Convenient sets of stations with matched "pump-tank" pairs are presented under the brand name Jumbo-60/35 with polypropylene, cast iron and steel containers.

Frequent water withdrawal leads to the regular inclusion of the pumping device. Such work affects the technical condition and long-term operation of all equipment.

Work in the water supply system is associated with some features:

Maintaining the pressure in the pipeline at a constant level.
A sharp change in network pressure during pumping, which is associated with water hammer.
Frequent activation of the pump.

In order to prevent sharp fluctuations in a closed circuit, the surface pump is equipped with a hydraulic accumulator.

The hydraulic accumulator is a reservoir designed to operate in three types of circuits:

cold;
hot water supply;
heating.

Surface installations work in conjunction with horizontal storage, which makes them compact. The container size is selected from among standard sizes, tailored to individual needs.

Autonomous supply in the absence of electrical energy.
Choice of installation location.
Low operating costs.

Do not forget that the creation of constant pressure in the absence of a well is possible only when using a container partially filled with gas.

When installing a small storage tank functional purpose design allows only to protect against water hammer. Another disadvantage is called a more complex and expensive design.

The best surface pumps for hot water

Ruler CNS (G) refers to multi-stage equipment. The temperature of the liquid lies in the range from 45°C (CNS) to 105°C (CNSG). The pressure indicator lies in the range of 44-220 m, and the flow is 38 m 3 / h.
household unit WILO Yonos has a "wet" rotor, provides a feed height of up to 7 m and independent adjustment of the power level.
Device with a "dry" rotor WILO VeroTwin with index DR-E works with liquids up to 120°C at high pressure (up to 16 bar).

For pumping hot water use the so-called circulation pumps. Closed loop required for hot water and heating systems.

The main requirement for the details of the device is resistance to temperature fluctuations. Therefore, many assembly units are made of cast iron, and insulation elements are made of ceramics or special elastic materials.

For pumping liquid, a combination is used: a powerful motor - a vane rotor.

Wet rotor installations differ in the way the components are cooled. Here, the moving fluid itself acts as a coolant.

The progressive scheme with a "dry" rotor differs in an isolated power part from a movable pressure mechanism. This design is more expensive.

Depending on the working conditions, the working machines are pumping stations different types:

centrifugal type models;
centrifugal-vortex units;
multi-stage installations.

For installations with a "wet" rotor, smooth pressure control, less noise, and reliability in operation are characteristic.
Units with a "dry" rotor have high performance and efficiency up to 80%.

Inexpensive models have an efficiency of no more than 50%.
Expensive devices require periodic maintenance.

The best surface multistage pumps

Lowara HM Designed to handle liquids without contamination. It has a head of 60 m, flow - up to 7.2 m 3 / hour.
Metabo P 6000 has 5 working steps. Provides delivery up to 55 meters at a pressure of 5.5 bar. Suction height up to 8 meters.
Wilo WJ 20EM– 2-stage station. Provides supply up to 38 meters with pressure up to 6 bar.

The use of a multistage pump is justified if the distance to the aquifer does not exceed 8-9 meters. Due to the use of several stages in the design, the water pressure is significantly increased compared to standard pumps.

Multistage devices are created on the basis of centrifugal mini-stations. This allows you to create a good pressure, while keeping the noise level and energy consumption low.

Feed - up to 7.5 m 3 / hour.
Pressure - up to 60 meters.
Developed pressure up to 6 bar.
The operating temperature of the pumped liquid is up to 40°C.

Advantages:

Multi-stage stations are reliable devices that do not require regular maintenance. Other benefits stand out:

smooth flow, without sudden pressure drops;
simplicity of design combined with a low price;
work with liquids with slight contamination.

Multistage pumps are characterized by certain disadvantages that limit their scope:

low efficiency;
limitation on self-absorption of water;
rapid overheating with a weak supply of liquid.

The best powerful surface pumps

Gilex Jumbo 70/50 P-50. The model has a fence depth of 9 m, and the feed is carried out at 50 m.
Grundfos IPBasic 3PT. The machine has an intake depth of 8 m and a feed of 47 m.
Gardena 500/5 "Comfort". Model with a fence depth of up to 8 m, supply - 45 m.

The power of the motors of the models due to the efficient design is in the range from 1.1 to 1.3 kW.

Power is determined based on the values of the characteristics of surface pumps:

Installed power, W. This range for home appliances ranges from 0.14 to 2 kW. The power of the motor affects the performance, the pressure generated and the operation in difficult conditions.
Efficiency. The range of efficiency for different units lies in the range from 45% to 80%.
Performance. The pumped-out volume of household appliances reaches 10 m 3 /hour.
The lifting height and intake depth depend on the location of the source and the supply object. Surface pumps have an intake depth of up to 10 meters, they are able to supply water at a distance of up to 60 meters.

high performance;
ability to provide water big house or plot;
availability of protection and control devices.

Powerful products have high power consumption and require more precise placement, fastening, and maintenance requirements.

Calpeda NGXM 3 pumps liquid from a depth of up to 9.5 m.
Machine with remote ejector – Pedrolo JDWm 2/30 creates a pressure up to 81 m, and the lifting height is 45 m.
Unit Unipump DP 750 has a lifting height of up to 20 m, and a head of up to 40 m.

For installations operating on the surface, a low depth of water intake is characteristic. This figure rarely exceeds 8-9 meters. An ejector is used to lift water from great depths. These devices are of two types:

integrated device;
external ejector.

The operation of the ejector is based on fluid recirculation. Part of the water during the rise returns back through a narrow nozzle.

When it enters the mixer, a vacuum cavity is formed, which causes water from a low pressure source to rise from the suction chamber into the supply pipe.

Using built-in ejector device allows you to increase the suction depth to a value of 3-5 meters, and callout helps to raise water from a depth of 30-50 meters. In the second case, the design is somewhat more complicated.

work with partially contaminated liquids;
do not react to the presence of air in the suction water.

An additional advantage of the external ejector is the low noise level during operation.

A common disadvantage of structures of any kind is low efficiency, since part of the energy is spent on auxiliary work.

Devices with built-in liquid return design create extra noise when turned on and require a separate room.

The best self-priming surface pumps

Model Grundfus JP. Lifting height - up to 8 m, and pressure - up to 48.
Car Wili PB-201EA. Raises water from 8 m, and the delivery range is 35 m.
Model Pedrollo CKM 50 differs from the previous machine in a large volume of pumped water - up to 2.4 m 3 / hour.

Everything lifting devices liquid starts to rise after pre-filling the suction pipe. The effect of self-absorption is achieved in the process of further work.

By design, the units are divided into two types:

centrifugal devices: single or multi-stage without ejector;
ejector centrifugal pumps.

The scope includes the following areas:

providing the house and other buildings with water;
watering the site, providing irrigation systems;
filling ;
pumping out liquid.

Pumps without ejector have maximum height liquid intake 10 m.

The thrust range depends on the power of the motor. Units with ejectors have a large intake depth: with a built-in design - by 3-5 m, and with an external assistant it increases by 45-50 meters.

simplicity and reliability of the design;
low noise level;
do not depend on the nature of the liquid;
minimum maintenance costs.

The weak point of the representatives of the group is called the low lifting height. The problem is solved by using an external ejector or by replacing the pump unit with a submersible model.

Vertical multistage pumps got their name due to the large number of pressure stages, as well as the vertical arrangement of the casing. They are used where it is necessary to obtain a high outlet pressure. In particular, abroad they are used for water supply of skyscrapers and other high-rise structures. They are also used for equipment booster stations and large irrigation systems. They can be used to fill water storage tanks located at a considerable height.

Rice. 1 - Various implementation options for vertical multistage pumps

These pumps are characterized by very high head and pressure. They are very reliable and can work continuously for long period time. Typically, the temperature limit of the pumped medium is usually 90-120 °C. The pressure is usually from 30 to 50 meters, and the productivity is from 1 to 250 cubic meters per hour. The housings are made of thick-walled stainless steel because the high pressure on the upper stages must be maintained. This type of pumps is distinguished by its compact size and weight, which makes transportation and installation much easier. Vertical arrangement housing allows you to install them in specially prepared niches, or in shafts in which pipes are installed.

Principle of operation and device

Multistage vertical pumps are driven by an electric motor. As with all dynamic vane pumps, the rotational energy of the shaft is transferred to the impellers, and then to the pumped medium, which passes through several impellers placed on one shaft. The housing has a sectional design. In fact, we can say that several pumps work at once in one building. The pressure created by a multistage pump is equal to the sum of the pressures created by each impeller separately. Multistage vertical pumps are subject to a special domestic standard - GOST 10407-83. According to him, the temperature of the working environment should be from 60 to 105 degrees, and the assortment is divided into two large subgroups: standard and high-speed models. The assortment from foreign manufacturers often goes beyond this standard, due to the fact that each manufacturer uses copyright patented solutions to improve performance.

Pump casings of this type consist of a certain number of discrete sections. They should be exactly 1 less than the number of pump stages, due to the location of the first wheel right in the front cover. This design solution reduces geometric dimensions pump. The number of sections can be adjustable, and then the pressure will decrease, but the volume supplied will remain unchanged. Typically, the pump covers are cast and are associated with the suction and discharge pipes, respectively. In the suction section, an oil seal must be installed, which is supplied with a water seal. Water is supplied to it through a special tube, which can be located in different ways, depending on the model and modification.

Rice. 2- circuit diagram vertical multistage pump devices

1 – motor housing, 2 – shaft, 3 – pump housing, 4 - power seal, 5 – impeller, 6 – chamber wall, 7 – outer protective cover, 8 – bearing, 9 – o-ring, 10 – bearing, 11 – pump supports, 12 – ring rubber gasket, 13 – lower support bearing, 14 – base weight plate

Usually the number of wheels in vertical multistage pumps can vary from 2 to 10 pieces. The pumped medium gradually passes from one impeller to another through a special channel, after which it passes the blades of the next stage. The guide channels form the so-called guide apparatus. This part and the impellers are sealed with special PPTE rings.

The main problem of all multi-section pumps is the increase in hydraulic force on the axis. It occurs with the so-called paraxial supply of the working medium. In order to reduce the effect of this phenomenon, special devices for unloading are installed on the axle. They look like a thick disk that takes part of the pressure on its plane. It is reinforced with the so-called hydraulic heel. For some designs of pumps, especially for those that are produced with a pair of impellers, multidirectional rotation is characteristic, so the force that occurs on the axis is mutually compensated. Also, to suppress the effect of this phenomenon, the surface of the case is covered with special spiral scattering channels, which significantly increase the surface area. Usually they are made by casting, and not by cutting.

Vertical multistage pumps with normal speed are usually made in sections, and the impellers are located at the axial inlets. They can supply volume from 8 to 860 cubic meters per hour, and the pressure is adjustable from 40 to 1500 meters. At the same time, of this type pumps have certain restrictions on suction height - no more than 7 meters, and even then not for all models. Usually this indicator is at the level of 4 meters. The pumps are characterized by high efficiency, up to 80%.

High-speed models have an increased flow, from 40 to 1000 cubic meters per hour, as well as a head from 136 to 1980 meters. For pumps of this type, a backwater of 3-6 m is required, and their efficiency also reaches 80%.

Rice. 3 - The discharge part of a vertical multistage pump may consist of a large number impellers.

The particularly powerful head of these pumps allows them to be used where other pumps cannot cope. For example, for pumping water from the mines of the mining industry. They are so reliable that there are mines that are constantly flooded, but the pumps do not fill the dungeon. It is these pumps that equip fire equipment used to extinguish towers and other very tall buildings. They also found domestic use.

Main design advantage multistage vertical pumps can be considered that sections can be removed or added. With one section, it will be a conventional centrifugal pump. It should be noted that the efficiency of such pumps is low, but none of the types has such a supply with such small dimensions. Disassembling them is also quite difficult.

Scope of use

Pumping liquid from wells and mines in the mining industry.

Can be used as submersible pump for very deep wells.

Supply of drinking and technical water to considerable height, v residential buildings, industrial premises and structures. For example, with the help of such a pump it is convenient to fill a water tower.

In fire systems to extinguish fires at high altitude.

Can be used at water supply stations to increase the pressure in the pipeline.

Fig.4 - Vertical multistage pump with closed impellers in section.

Used in agriculture for fast filling large containers, as well as for pressurization. These pumps can be used to provide uninterrupted water supply to a farm or poultry house.

In industrial water supply systems on various technological lines.

In washing installations, as well as in treatment facilities and at aeration stations

In power supply systems for hot water boilers and various heating systems.

Powerful water filtration systems, including reverse osmosis technology.

Manufacturers themselves often position their pumps as multipurpose.

Advantages

Vertical multistage pumps have a fairly simple design, which allows the use of a wide range of materials to improve the quality of the transfer of the pumped medium.

They take a lot small area, therefore, they can be placed in special serviced niches in a common shaft along with pipes, which provides additional sound insulation.

Centrifugal pumps can operate at almost any rotational speed, so the motor can be connected by direct drive, which greatly simplifies the design and also makes the pumps more compact.

Vertical multistage pumps provide a uniform flow of the pumped medium, and also demonstrate excellent performance stability at any time of operation.

They can work for almost months without shutting down and without any consequences.

Costs for Maintenance of this type of pumps is much less than for any other pump that provides a powerful supply.

Fig.5 - An example of connecting a vertical multistage pump for water supply of a high-rise building.

These pumps are allowed a short time idle work. Usually during this time, emergency power off systems have time to work, or a manual shutdown is performed. The pump is not damaged during this time.

If we compare vertical multistage pumps and any other type in the same size, then the former will be much smaller in size with the same performance.

Flaws

In a single-stage version, such a pump is of no interest, because it develops an extremely low pressure, and its efficiency is very low, and may not reach 30%.

Multistage pumps are very difficult to manufacture, so they are not cheap.

To reduce the number of stages, rotation at higher speeds is necessary, which in turn places high demands on pump materials.

Rice. 6 - Destruction of the impeller on one of the upper stages due to dry running

Typically, these pumps are not self-priming, which makes it difficult to start under certain conditions.

There is a severe limitation on the viscosity of the pumped medium, since the axial forces increase significantly.

Centrifugal multistage pumps are fairly common varieties of dynamic hydraulic machines. They are widely used in water supply and sanitation systems, in the chemical and nuclear industries, in thermal power engineering, in aviation and rocket technology.
What features of the devices, their advantages, how to mount the units with your own hands is described in this article.

Types of centrifugal pumps

Aggregates can be classified according to the following features:

By number of steps:

single-stage units;
two-stage;
multistage.

What is the number of fluid flows:

single-threaded;
with two streams;
multithreaded.

By what principle is fluid supplied to the impeller:

with spiral outlet;
along the annular outlet, with a guide vane;

What design of the impeller:

closed ;
open impeller.

How the drive is made:

using a coupling;
through the gearbox.

Shaft location:

vertical;
horizontal.

pump with wet rotor. In this case, the motor rotor moves directly to the fluid. The motor stator, which is constantly energized, is separated from the rotor by a special sleeve, 0.1 to 0.3 mm thick, made of stainless steel.
The rotor bearings are lubricated by a liquid medium, which also performs the function of cooling the rotor. The pump shaft is generally horizontal.
Pump with a dry rotor. Here, the motor rotor does not come into contact with the liquid medium that is pumped. They tend to have a large liquid supply.

Advantages and disadvantages of centrifugal pumps

Compared with other types, centrifugal pumps have the following advantages:

In a wide value of the supply range Q, rather high values of efficiency and pressure H are preserved, as a result of the flat characteristics H = f(Q) and η = η (Q.
Increased speed, which allows pumps to be driven by electric motors and turbines.
Power changes N has a smooth shape, which allows the pump to be started with the outlet valve closed or with the non-return valve closed.
They have good stability in the operation of devices and the expansion of the technical values of H and Q with parallel and serial connection pumps, when working on one pipeline.
Transient processes flow smoothly, with changes in the operating modes of hydraulic systems.
The pumps are located above the liquid level in the flow tank.
Due various factors the performance of the pumps H, Q, η changes. These factors are:

turning the diameters of the impellers;
change in rotational speed;
change in power supply frequency.

The low price of the pump, which is associated with the use of relatively inexpensive structural materials in the composition of the product:

become;
cast iron;
polymer materials.

Ease of maintenance and operation.
High reliability during operation.
Large fluid supply Q.
With small uniform pressure pulsations, the fluid flows.
Successfully work on the "contaminated" liquids.

The disadvantages of centrifugal pumps are:

It is necessary to fill the unit before starting it.
They are prone to cavitation.
Reduced efficiency when pumping viscous liquids.
Low value of efficiency, with a small supply of liquid Q.
it is better to use in the area of high water supply Q and low and medium pressure H.

Tip: You can not use such devices without first filling with water.

The principle of operation of multistage centrifugal pumps

The instruction for multistage pumps indicates that they are used for pumping hot and cold water.
In this case, they can be used to ensure:

Heat and water supply.
Increasing pressure.
Firefighting.
For feeding steam boilers.
It is used in industrial circulation, washing, irrigation, air conditioning and watering systems.

The centrifugal multistage pump functions due to the rotation of several wheels at once. In this case, the liquid that sequentially passes through the wheels moves rapidly through the pipe.
In this case, the pressure of the water supplied to the water supply directly depends on the sum of the pressures of the elements arranged in series that carry out the same supply. Each stage adds flow pressure, which depends on the power of the wheel, and the total pressure of the pump will be equal to the sum of the pressures of all its stages.
According to the location of the piston, pumps are divided into two types:

Horizontal. This device is an excellent option for increasing the pressure for water supply in an apartment or private house.
Such a unit will successfully cope with the organization autonomous water supply. Most often, horizontal pumps are made surface, their design does not imply immersion in the pumped medium. Devices are also used to solve more specific problems:

they are mounted for the device of the irrigation system of the site;
to speed up the filling of the pool.

Vertical (see). When the well is located near the house the best option, to provide water at home, there will be a multi-stage vertical pump device.
With it, you can pump water from a depth of up to 20 meters, which is enough to meet the requirements of almost all buyers.

The device of centrifugal pumps

The main elements of the unit:

Here are the positions:

1 - element for fixing the drive shaft.
2 - clutch.
3 - main shaft.
4 - sealing element.
5 - rotor.
6 - rings.
7 - inner sleeve.
8 - head.
9 - bowl.
10 - internal body.
11 - lower insert.
12 - column.

Below are the main components of the device.

The main components that make up the multistage centrifugal pump are:

Frame. Provides tightness of the connector of the product, rigid fixation from any displacement of all its elements, and at the same time the necessary working clearance in the flow part is guaranteed.
Fixed compression control ensures the use of a special metal-to-metal gasket in the radial connector. Any displacement that may be caused by thermal expansion is guaranteed by a casing support located in the center line of the pump. For its manufacture, high-grade steel is taken.
Rotor assembled. It is the basis of the unit. Greater reliability and performance are ensured by the accumulation of high technologies.
Its design allows the device to work with specific liquids at maximum performance. These are single-suction impellers rigidly fixed on the shaft and closed type. Rotors and impellers are dynamically balanced.
balancing disk. It serves to reduce the load to the optimum value, which increases the life of the bearings.
The element is behind the last impeller. At the same time, it reduces the spacer force on the rotor shaft, which is caused by the impellers, which reduces the load on the bearings.
main shaft. Provides minimal shaft misalignment to maximize bearing and seal life.
Shaft seals. All types of seals with API 610 standards are mounted in a horizontal plane.
Deflectors and end seals. They serve to ensure a guaranteed volume of oil in the bearing assembly and keep the assembly from foreign mechanical impurities.
Impellers or impellers. The latest computer programs, using hydrodynamics, have made it possible to design wheels with optimal performance and improved dynamic characteristics.
In order to minimize shaft vibrations and balance its rotation, the impellers are fixed on the shaft with a press fit, using split rings and double-acting wrenches.

In addition to the above designs, multistage centrifugal pumps are used, which are connected to the engine through a multiplier.
A multistage centrifugal pump is used for heavy duty applications such as fertilizer production or other high pressure processes in the gas processing industry. Its diagram, with the connection of the engine through the multiplier, is shown in the photo:

Tip: When choosing a pump of any type, you need to be guided by its parameters. Qualified specialists will help you choose the right product.

Details of the operation of multistage centrifugal pumps can be seen in the video in this article.

Centrifugal pumps are the most common type of pumps among a wide range of pumping equipment presented in Ukraine. Thus, more than 50% of the pumping equipment market falls on centrifugal pumps. Waterpass offers centrifugal pumps from well-known foreign manufacturers: Salvatore Robuschi, Varisco, JEC.

The secret of the popularity of centrifugal pumps lies in their high performance, durability and wide range of applications. Pumps of this type are used in water supply and drainage, metallurgical, oil, chemical, food and other industries. Regarding the strength of centrifugal pumps, it should be noted that they are designed for constant pumping and their parts are practically not subject to wear - and this indicates that there is no need for frequent replacement of equipment parts, which allows you not to make significant expenses like financial resources enterprises, and time for idle production. In addition, the design features make it easy and quick to service the pump. Centrifugal pumps are also attractive due to the possibility of using them in conditions of increased hygiene requirements, ultra-high temperatures (up to + 350 ° C) and in conditions of interaction with chemically aggressive substances. One of the most significant aspects of the attractiveness of centrifugal pumps in the pumping equipment market is their high performance. The minimum pumping volume of centrifugal pumps is sometimes equal to the average of other types of pumping equipment, and their maximum productivity reaches about 2.5 thousand m 3 per hour.

According to the installation principle, centrifugal pumps are divided into monoblock and cantilever.

Separation of pumps according to the installation principle.

Single-stage centrifugal pumps are widely used in many fields of activity and are designed for pumping water, suspensions, emulsions, chemically active liquids, and are also installed in underground pumping stations.

Single stage RC pump.

Single stage RD pump.

Single stage RDL pump.

Single stage RS pump.

Multistage centrifugal pumps are characterized by their ability to achieve high heads with relatively small flows. Multistage pumps are divided into sectional and scroll. A sectional type multistage centrifugal pump pumps liquid through the guide vanes of each of the sections sequentially from one wheel to another. The delivery of pumps of this type reaches 850 m 3 / h, developing a head of up to 1900 m.

Multistage scroll pumps have a number of advantages over sectional pumps. So, they are characterized by a higher efficiency, ease of assembly and disassembly, balanced axial pressure, and the absence of guide vanes, which makes it possible to significantly turn the wheel without a significant decrease in the efficiency of the device.

Multistage centrifugal pumps are used in heating systems, water supply and air conditioning systems, hot water supply, for irrigation and fire fighting, and can also be used for pumping aggressive media.

Multistage pump TS.

The choice of a particular pump requires the determination of a number of parameters and the consultation of a qualified specialist. The type of centrifugal pump that will meet all customer needs will be determined by a Waterpass consultant.

Those who are familiar with the operation of compressor units will understand immediately. In fact, the principle of operation of multistage pumps is practically the same. The pumped liquid sequentially moves through the sections, in each of which its pressure increases. The water pressure at the outlet of the device is determined by the total value created by it at each stage.

Such technical solution gives certain advantages to multistage pumps over traditional analogues.

One device, no additional elements, included in the system, creates an increased pressure in the pipe (up to 400 m). Considering that in most private buildings there is a complex water supply scheme, with several “points” of liquid analysis and a significant distance from the source (well, well) from the house, plus more than significant.
Relative noiselessness. There is no need to talk about the complete absence of sounds from a running engine, but their level is so insignificant that this is not taken into account. This is explained simply - to create the proper pressure, it does not make sense to use an overall motor in the pump. In multi-stage models, the pressure is increased due to the synchronous operation of several wheels. Therefore, they are characterized great combination indicators such as power and generated pressure. This is the third plus of this group of devices.

Are there any disadvantages of multistage pumps? From point of view practical application only one - they are only suitable for working with clean liquids. It is understood that only the smallest fractions are allowed in the water (contamination up to 100 g / m3), otherwise the efficiency of the device drops sharply, and the resource is reduced.

Many put multistage pumps at a minus their high price. Yes, they are about 2.5 times more expensive than traditional counterparts. But an analysis of all aspects of their practical use shows that the installation of this particular device is sometimes more expedient. The fact is that to create the same pressure, if you purchase a model with one impeller, you will need a product with more power. A this characteristic directly affects its price. In addition, the increased power consumption cannot be discounted. Therefore, the savings are almost zero, and in terms of ease of installation (due to compactness), multistage pumps are preferable. And yes, they are cheaper to run.

How are devices in this group classified? They differ in the spatial orientation of the shaft on which the impellers are located. Vertical pumps- these are submersible models, and horizontal ones are mainly surface ones. To provide private buildings with water from an autonomous source, devices of the latter type are mainly purchased. The fact is that they are more versatile and can be used for other purposes. For example, to increase the pressure on the track. One of the representatives of models of this type - MN 500C - you can get acquainted with its characteristics and cost by clicking on the link.

When choosing a multistage pump, it is better to focus on domestic devices. First, there will be no problems with the repair of the product. The same seals must be changed periodically. Secondly, our engineers take into account Russian specifics, first of all, water quality. Consequently, pumps made in Russia will last much longer.
Consultation of a specialist of choice optimal model it won't be redundant either. It will not work to take into account all aspects of the use of a multistage pump, to correctly understand its characteristics and determine the required values \u200b\u200bof the quantities without having sufficient specialized knowledge, it will not work. Therefore, it is not a fact that the money will be spent rationally, and the result will meet expectations.