Submersible pumps for wells and wells: selection and connection diagram

A pumping unit is the main element of any water supply system. The efficiency and reliability of the entire system largely depends on the correctness of its choice.

For the arrangement of wells and wells today, two types of pumps are used - surface and submersible.

We will talk about the existing varieties, technical parameters and features of the choice of submersible installations in our article.

Types and characteristics of submersible pumps

According to the principle of operation, submersible installations designed for pumping clean water are divided into four categories:

• vibration;
• centrifugal;
• vortex;
• screw (screw).

The former are used to supply water from wells and wells dug in sandy soils. Their main advantages are reliability, simplicity of design and affordable price. The most popular brands are "Rucheyok" and "Kid".

The principle of operation of the vibrating pump is the interaction of the magnetic field of the coil with a steel rod, on which a rubber diaphragm is mounted. Alternating current causes the rod to oscillate at a frequency of 50 Hz. They are transferred to an elastic diaphragm, which creates a vacuum in the working chamber. Under its action, water from the source moves into the pump housing and is pushed out of it into the water pipe.

When choosing a submersible pump for a well or well, one should not forget about the advantages of centrifugal installations. They are able to lift water from a great depth, therefore they are used not only in wells, but also in artesian wells. The basis of such a pump is a wheel with blades mounted on an electric motor shaft. When it rotates, pressure is created in the housing, pushing water into the supply line.

Submersible centrifugal pumps

According to the design features, single and multistage centrifugal pumps are distinguished. The number of lifting steps they have is equal to the number of impellers with blades. The more of them, the more powerful and productive the installation.

Vortex pumps are similar in principle to centrifugal pumps. They are used to lift fluid from deep wells.

The name of the screw pump speaks for itself. The main element of the installation is a screw (auger), the rotation of which creates pressure in the working chamber. Such pumps are placed in artesian wells and wells. They are distinguished by high reliability and the ability to pump liquids with a large amount of abrasive particles (sand) without breakdowns.

Water supply scheme using submersible pumps

For the correct installation of the water supply system, it is necessary to clearly understand what elements it consists of. Beginners in this business will be helped by the connection diagram of the deep pump, which indicates their location and name.

It should be noted that there is no fundamental difference in connecting vibration, centrifugal, screw and vortex pumps. All these units are paired with a check valve, which is placed next to the pump or in front of the hydroaccumulation tank.

The installation of a deep pump does not bypass the use of a pressure switch in the water supply circuit. It is responsible for maintaining the pressure in the line within the limits specified by the user (or manufacturer).

Motor protection against overheating (when the water level drops below the pump) is provided by a dry-running relay mounted on the water pipe. It should be noted that a submersible pump equipped with a “frog” float switch does not need to install such a relay. When the water level drops below its body, protection is triggered and the engine turns off.

A hydraulic accumulator tank is necessary for the operation of any pumping unit (both deep and surface). This is a buffer element that reduces the frequency of switching on the pump, extending its life. If there is no hydraulic accumulator in the system, then the engine will turn on after each opening of the water tap and the pump will quickly fail. You can do without it only if a storage tank with a level sensor is installed in the attic of the house. After pumping water into it, the pump turns off until the liquid is used up to the level set by the user. After that, the sensor will give the pump a command to turn on and the cycle will repeat.

A drain valve on the line is also required. Without it, you will not be able to free the pipes, boiler and storage tank from water for repair or maintenance of the system.

In what cases is it advantageous to install a submersible pump, and in which pumping station?

Gathering, you need to solve the issue of choosing the type of pumping unit.

A surface station is the best option for such initial data of the water supply system:

1. The distance from the water source to the building is small (15-20 meters).
2. The lifting height does not exceed 8-12 meters.

If the well or well is deep, and you need to pull at least 30 meters of a water pipe to the building, then it is better to buy a powerful submersible pump. An important plus of such a unit is reliability in operation and the absence of the need for insulation of the pit (when installed in the yard).

Since the submersible pump is located in a well or well, the noise from its operation in the house is not heard. The pumping station, on the contrary, even when installed in the basement, needs good sound insulation.

There is one purely psychological moment that affects the choice of a pumping station, all other things being equal to the supply conditions (pressure, productivity) with a submersible pump. This is a higher assembly readiness of the installation. In one module, a pump, a hydraulic accumulator, a pressure gauge, a pressure switch and a dry-running protection relay are mounted here. With a submersible pump, the main components are supplied separately, so it is not easy for beginners to assemble them into a single system.

Manufacturers have found a way out of this situation and offer customers household submersible installations, consisting of only two parts - a pump and an automation unit already connected to a hydraulic accumulator tank.

How to choose the right submersible pump?

If in the last century the pump "Kid" or "Brook" was the dream of a summer resident, today a huge range of submersible pumps is presented on the market.

At the same time, the installation selection algorithm remained unchanged and includes only two parameters:

1. Pump capacity (m3/h);
2. Pressure (meters).

These two quantities are inversely proportional to each other. This means that the more productivity the installation develops, the less depth it will be able to raise water.

To illustrate this fact, we propose to study table No. 1, which shows the relationship between the main parameters of the pump.

In the pump passport, the manufacturer indicates two extreme values: maximum flow (capacity) and maximum pressure. Therefore, when buying a pump with a head of 85 meters, remember that with such a rise, its supply to the water supply will be zero. The actual performance of the unit is in the middle. They should be taken into account when studying passport data.

Let's answer together the question of which submersible pump is better to choose, based on the data in table No. 1. Let's say that the height of the rise in the well (or well) is 8 meters (6 meters to the water table + 2 meters to submerge the pump). The distance to the house is 30 meters, the height of the water in the house (to the second floor) is 5 meters.

For simplicity, the pressure loss in a horizontal section of a water pipe is assumed to be 1 meter per 10 meters of pipe length.

Another value that must be taken into account is the pressure loss to overcome filters, tees and pipe bends. You can accurately calculate it using special tables. We will approximately take this value equal to 10% of the head.

Water must enter the accumulator at a pressure of 1.5 to 3.0 atmospheres (bar). This will additionally require from 15 to 30 meters of pump pressure (we take 20 meters for calculation).

The final figure will look like this:

1. Vertical rise - 8 + 5 = 13 m.
2. Horizontal feed - 30 m x 0.1 = 3 m.
3. Creation of pressure in the system - 20 m.

Total: 13 + 3 + 20 \u003d 36 m + 36 x 0.10 (for losses) \u003d 40 meters of pressure.

In our table, this pressure corresponds approximately to a pump capacity of 0.55 m3 / h. Is it a lot or a little? For a family of 2-3 people is enough. For more residents, a more productive installation will be required.

The everyday principle "buy with a margin" when choosing a pump is only partially justified. If you buy a unit whose pressure is 20-25% higher than the calculated one, this is normal. If it exceeds it by 2 times, then you will definitely overpay.

Popular brands and estimated prices

Choosing a deep-well pump, each person tends to buy not too expensive, but the most reliable product.

The German brand Grundfos (Grundfos), as well as the Italian Pedrollo (Pedrolo) and Dab (Dab) deserved high user ratings. Their pumps are of high build quality and reliability in operation.

Anyone who is not constrained by means prefers to buy a submersible pump for a well with automation from one of the indicated brands. Estimated prices for units of average productivity (3 m3 / h) and pressure (70 meters) here are in the range from 25 to 60 thousand rubles.

Models of units designed for wells in the average price range are slightly cheaper from 17 to 30 thousand rubles.

The cost of submersible pumps for wells and wells of domestic manufacturers Belamos, Aquarius, Caliber and Dzhileks is more democratic. The price of the simplest models for water supply from a well starts at 2 thousand rubles. Downhole units cost an average of 9 to 18 thousand rubles.

AQUARIUS BCPE 0.5 - 40 U

Popular among summer residents, vibration-type pumps "Brook" and "Kid" occupy the lowest price group, despite good performance. You can buy such equipment at a price of 1,600 to 2,800 rubles.