Hydraulic tanks for an autonomous water supply system. Hydraulic accumulator for water supply: device features, choice of volume, operating pressure, installation methods Hydraulic accumulator with water tank

Hydraulic accumulators are important element water supply systems country house. It performs several important functions: it increases the reliability of the water supply system, increases the comfort of use and extends the service life of pumping equipment.

This review describes the device and principle of operation of a hydraulic accumulator for water supply, how to connect it yourself, and its possible malfunctions.

Operating principle and device

In houses with individual water supply, the water pressure is created by its own pump. When you open the tap, water begins to flow and the pressure in the system drops. When it decreases in the system, the pressure sensor is triggered and turns on pump equipment.

In order to reduce the number of pump starts and stops, water hammer, overpressure Storage tanks are used to accumulate water reserves in the system for peak consumption. They are also called expansion tanks.

Let's look at the principle of operation of a hydraulic accumulator. This element of the system is a metal tank that is only partially filled with water. The second half of the container is filled with air.

Water and air are separated by a rubber membrane. When the tank is filled with water, the air is compressed and the pressure in the tank increases. When you open a water tap, the pressure will not drop immediately, but as the storage tank empties. Thanks to this, the pressure sensor will turn on the water pump less often and this will extend its service life.

Installation of expansion tanks for water supply

There are two types of these devices: for water supply and heating systems. Hydraulic water supply accumulators are easily recognizable from the photo, have characteristic shapes and are usually painted blue. Heating equipment is painted red.

To be completely sure, you should read the documentation for your existing equipment. They differ in that in tanks for heat supply they use technical rubber, not food grade rubber, and in these tanks it is not always possible to replace the rubber on your own. In red tanks, a membrane is often installed with a fastening in the middle of the tank.

Hydraulic accumulators for water supply systems have two standard options designs based on the method of separating liquid and air: membrane and bulb devices.

In the first type of storage tank, air and water are separated by a rubber membrane. It is attached in the middle of the tank. Water comes from below, and on top there is a spool for pumping and bleeding air. Such tanks are mounted vertically.

Bulb storage units are installed horizontally. In them, a rubber bulb is filled with air, and the volume around it is filled with water. The end of the bulb is attached not in the middle, but from the end of the tank to the flange and therefore it is easier to change than the membrane

.

There is no fundamental difference between the two types of structures. They differ only in the method of fastening, which must be taken into account during installation.

Selection and installation of equipment

Equipment is selected based on the planned water consumption at peak consumption. The larger the capacity, the fewer cycles of on and off the pumping equipment will perform with the same cycles of opening and closing water taps.

Standard containers of 24 liters are usually used, but large containers with a volume of 100 liters or more are also produced, which are installed in buildings with a large number water consumers. For example, with a small container, the pump will first turn on after washing your hands in the bathroom and putting water in the kettle, and the second turn on will happen after flushing the toilet.

With a large water tank, the pump will only turn on once after these three operations. In any case, the system will work with both a large and a small tank.

The choice of equipment depends on the wishes of the owners and the ability to place such a device in the room. The small tank can be placed even under the sink, and the large tank is installed in separate room usually together with pumps. When installing, you should take into account its weight and provide for the possibility of draining water from it.

Diagnostics and troubleshooting

About incorrect operation storage tank indicates frequent activation of the pump. This may be caused by a lack of air in the tank due to a ruptured membrane, or by bleeding it through the valve.

In this case, the pressure drop in the accumulator and the pump will turn on almost instantly when the water is turned on. To eliminate this malfunction, it is necessary to pump the tank with air or replace the rubber membrane.

Conclusion

The expansion tank is an important element of the plumbing system. Hydraulic accumulators for water supply systems can be easily connected or replaced on your own. It can be repaired at home. Operational problems are easily identified and corrected.

Photos of hydraulic accumulators for water supply

A hydraulic accumulator, also known as a storage, pressure or expansion tank, is a necessary element for a closed water supply system in any private home. In order to correctly select and use such an accumulator, it does not hurt to study the principle of operation of the hydraulic accumulator, the types, causes of breakdowns and how to eliminate them. In addition, it doesn’t hurt to figure out how the red and red tanks differ. of blue color.

How does a hydraulic accumulator work?

Hydraulic accumulators are often called hydraulic accumulators because inside such a device there is a special rubber gasket - a membrane. It divides the container into two parts. On one side of the membrane there is water, on the other there is air or intervening gas. Also, the hydraulic tank is usually equipped with a hole for water supply and a pressure gauge that reflects air pressure.

Typically the hydraulic tank consists of a metal body and a rubber membrane. In addition, a spool is installed that regulates the air supply and bleed, as well as a filter to remove small contaminants

Water is supplied to the water supply system using a pump and pumped into the tank. As a result, the gas pressure in the automatic accumulator increases. When it reaches the maximum permissible value, the automatic control system turns off the pump and the water supply stops.

The diagram clearly shows the principle of operation of a hydraulic tank in a water supply system. The device is controlled automatically, which increases its service life

Gradually, the water from the tank is consumed. The pressure decreases, reaches the minimum specified limit, after which the automatic control system turns on the pump. Water enters the tank until the pressure reaches set value, the pump turns off, etc.

Why is such a drive needed?

If there is a hydraulic tank, the pump on-off cycle occurs only when it is necessary to fill the tank with a sufficient supply of water. If there were no hydraulic accumulator, the pump would turn on every time one of the household members opens the tap. The presence of a storage tank in the system allows:

• significantly increase the service life of the well pump;
• prevent harm from possible water hammer in the system;
• maintain a certain pressure in the system;
• prevent breakdowns of elements of the water supply system and plumbing equipment.

It is obvious that hydraulic accumulators for closed water supply are simply necessary. The role of the storage tank in the water supply system is described in detail in the following video:

Types of membrane tanks and their features

There are vertical and horizontal hydraulic tanks, which are mounted differently at the installation site. There is one more important point. In the part of the hydraulic tank that contains water, a small amount of air can accumulate over time. This air should be periodically removed to prevent air pockets, which are quite dangerous for it, from entering the system. In vertical containers, air accumulates at the top and a special nipple is used to remove it.

With horizontal hydraulic tanks everything is somewhat more complicated. To bleed off accumulated air, you will need not only a nipple, but also a ball valve, as well as a sewer drain.

Owners of small hydraulic tanks with a capacity of less than 100 liters need to get rid of excess air differently. To do this you should:

1. Turn off power.
2. Open the mixer tap.
3. Wait until the tank is empty.
4. Close the tap.
5. Connect the system to power to refill the tank.

Excess air will escape along with the water. This procedure should be done at least once a month.

Red hydraulic tanks are designed for hot water supply systems. Although the membrane in them is made of fairly durable rubber, they should not be used for feeding cold water

Manufacturers offer hydraulic tanks in red and blue, as well as colorless ones. Blue devices are intended for use in a cold water supply system. To make the membrane in such tanks, food grade rubber is used, which is safe for human health. Red hydraulic tanks are intended for heating and hot water supply systems. It is not recommended to use them for cold water, since the membrane in such tanks is made of a different rubber. In addition, the operating pressure threshold for blue hydraulic tanks is higher and reaches 8 Bar.

Typically, water enters the storage tank from below, and on top, as already noted, there is a nipple through which air is discharged. Therefore, each device has two threaded connections(usually inch or half inch), which should not be confused. They are often installed on the upper nipple automatic device for air removal.

Sometimes there are situations when water is supplied to the hydraulic tank from above. It is believed that in this case automatic air venting will not be needed. But you should take care of the filter so that sand particles or other contaminants do not enter the system.

Note! The consumer is offered a wide variety of models of hydraulic tanks from foreign and domestic production. Not all imported devices are adapted for Russian system water supply, which significantly reduces the period of their uninterrupted operation. As practice has shown, domestic hydraulic tanks High Quality last longer.

Pay attention to the material about the design and operating principles of pumping stations:

Causes of breakdowns and ways to eliminate them

The most vulnerable part of the hydraulic tank is the rubber membrane. During operation, it is constantly stretched and then contracts. Gradually, the rubber loses its elasticity and breaks. The following symptoms may indicate problems with the hydraulic tank:
water comes from the system in small portions at high pressure, the tap seems to “spit” water;
the pressure gauge needle suddenly reaches high values ​​and then immediately drops to zero.

Rubber membranes for hydraulic tanks can have different shapes and sizes. When replacing the membrane, use a product designed for a specific hydraulic tank model

To make sure that the membrane is torn, you need to press the nipple spool to release air from the storage tank and determine what air pressure is in the accumulator. If at the same time the pressure gauge needle immediately goes down, it means that there is very little air left in the hydraulic tank that provides the necessary pressure. It is necessary to completely bleed the air, if after this water flows from the spool, then the membrane is definitely torn and repairs are necessary. If the water does not flow, the membrane is intact, and the air leaves the container through the cracks that have appeared, faulty connections or the spool.

Problems with the hydraulic tank in the hot water supply system may be indicated by a small leak that appears at safety valve water heater. You should proceed in exactly the same way: press the spool valve nipple, estimate the amount of air, bleed it completely and determine by the presence or absence of water whether the hydraulic tank membrane is intact.

Replacing the membrane in a hydraulic tank is not that difficult; in addition, it is much cheaper than installing a new device. For repair you will need:

1. Purchase a new membrane that exactly matches the torn one.
2. Carefully disassemble the hydraulic tank by unscrewing the connecting bolts.
3. Remove the torn membrane.
4. Install a new membrane in its place.
5. Assemble the hydraulic tank.
6. Tighten all bolts evenly.

The main danger in this case is that improper handling of the device can lead to the edge of the membrane slipping into the metal case. As a result, the work will have to be redone. To prevent this from happening, it is recommended to tighten the connecting bolts gradually to ensure even tension on the membrane. Problems arise when one bolt is fully tightened before working on the next one. At the same time, the edge of the membrane shifts and can slip off.

You will learn about common malfunctions and how to fix them in our material:

Another mistake is using sealant at joints. The use of such compounds leads to a reduction in friction between rubber and metal. As a result, the edge of the membrane moves and the joint density decreases, which can cause water leakage in the future.

A country estate, as a rule, does not have central water supply. In this case, the source of water is a well or well, from where the liquid is pumped into the home water supply system using a pump.

Water consumption is not a constant value. Sometimes you need to draw a glass of water from the tap, and other times you need to fill the bathtub. In both cases, when the tap is opened, the water pressure is the system will fall and the pump will turn on, but if for a bathroom the pump runs for 10 minutes, then for a glass of water 5 seconds will be enough. And if you need to draw several glasses of water at intervals of half a minute, the pump will turn on for each of them - this mode of operation is unacceptable for an electric motor and it quickly breaks down. To prevent this from happening, a hydraulic accumulator for water supply systems is built into the pipeline.

A hydraulic accumulator in a private home will help avoid problems with water supply

Purpose and principle of operation

The main task that falls on hydraulic tanks for water supply systems is to accumulate a certain volume of liquid and release it into the water supply system when the pressure in the pipes drops. Thus, the system has a supply of water and when the taps are opened briefly (to fill the kettle with water or rinse your hands), the pump does not work, since the water comes from the hydraulic tank.

As a result, the main principle of operation of a hydraulic accumulator in a water supply system is to reduce the number of on/off switches of the water pump, and therefore increase its service life.

Structurally, the hydraulic tank is a sealed hollow cylinder made of metal. Inside there is a membrane, also called a “pear,” made of special rubber - butyl or synthetic ethylene-propylene rubber. These materials are durable, meet all sanitary and hygienic requirements and are resistant to bacteria. The membrane divides the cavity into two parts, in one of which water accumulates. The second is occupied by compressed air, which pushes water from the hydraulic tank into the system when the tap is opened.

The device consists of a hollow cylinder and a flexible membrane inside

The hydraulic accumulator operates cyclically:

When the water pressure in the system decreases (when water has already been selected from the hydraulic tank), the pressure sensor is triggered and the pump starts to supply water.

The “pear” is filled with water, its volume increases. The air is compressed, the pressure in the tank increases.

The pressure switch gives a signal and the pump stops working.

When water is consumed, the pressure switch is activated again and the cycle repeats.

Beginning and end of the accumulator operating cycle

Advantages of installing a hydraulic tank

There are a number of reasons why a hydraulic accumulator is needed in a water supply system:

The main task is that thanks to the hydraulic accumulator, starting and stopping the pump occurs less frequently. The engine does not overheat and does not fail longer.

In addition to creating a supply of water, the storage tank softens hydraulic shocks in the water supply system. The air contained inside the cylinder reduces pressure drops in the pipeline due to its ability to compress. As a result, all elements of the system wear out less.

During a power outage, a reserve supply of water remains in the hydraulic tank, which is important in case of frequent power outages.

Types of structures and their structure

Depending on the pump used and location pumping station, hydraulic accumulators of horizontal and vertical installation are used in everyday life.

These types of molding allow them to fit into the space of any technical room. The unit must be installed with ease of maintenance in mind. It is necessary to provide access for repairs and, if necessary, drainage of water.

Vertical and horizontal hydraulic accumulators will fit into any room

On our website you can find contacts of construction companies that offer installation and design services for sewerage and water supply. You can communicate directly with representatives by visiting the “Low-Rise Country” exhibition of houses.

It is most rational to connect horizontal hydraulic tanks to external pumps, and vertical ones to submersible ones, but in any case final decision must be taken on site depending on the parameters of the entire system.

In operation of the units fundamental differences No. The difference is in the method of bleeding off excess air that accumulates in the plumbing system during operation. When large volumes of water pass through the storage tank, dissolved air is released from it. It can create air pockets and impede the system's operation.

In designs with a vertical cylinder, the hole with the valve is located in the upper part of the unit, because air collects at the top of the cylinder. Horizontal hydraulic tanks usually do not have such a device. Additional installation of pipeline from ball valve, drain tube and nipple.

There are no devices for air release in storage tanks with a volume of up to 100 liters. Excess gas is removed after the water is completely drained.

Water is drained using a standard tap at the inlet

Why you need to know how to select a hydraulic tank

In order for the equipment to function well and provide water to the residents of the house, you need not only to know what a hydraulic accumulator is for water supply systems, but also how to choose it correctly.

If the storage volume is insufficient, the pump will work in enhanced mode in order to provide the necessary pressure in the network.

If the volume of the hydraulic tank is excessive, there will be no such problem; in addition, there will always be a certain volume of water in the tank, which can be used, for example, in the event of a power outage. But you shouldn’t chase the size, because the main purpose of the equipment is to maintain pressure to distribute liquid in the network. And to store water, you can choose another, less expensive tank, for example, made of plastic.

Each thing has its own purpose - storing water “in reserve” is better suitedregular plastic container

Calculation of the optimal volume of the hydraulic tank

A correctly selected hydraulic tank volume will allow:

ensure a sufficient level water consumption,

optimal use of pumping equipment,

extend the service life of the drive and system elements.

There are several ways to select a hydraulic accumulator for water supply systems and calculate the required storage volume.

Italian engineers have developed a calculation method UNI 8192. Selection is carried out according to three parameters: maximum water flow, the number of permissible pump starts per hour and the water supply height.

If the need for water supply is small, for example, for a family of 2-3 people living in a one-story house, the volume of the hydraulic tank can not be calculated. A 24-liter container will be enough.

For houses with more floors and with a considerable number of water consumption points, a calculation should be made.

The required hydraulic tank size can be selected only based on calculations

It is carried out according to the scheme:

The tables determine the total coefficients of water consumption depending on the equipment used.

The maximum water flow is calculated. For example, when a shower, cistern and faucet work together in the kitchen, this figure will be 30 l/min (Qmax).

The estimated number of pump starts per hour (for comfortable operation) is taken as a=15. With more intensive work, the hydraulic tank membrane oscillates too frequently, which leads to its premature destruction. In addition, the pump’s performance does not make it possible to completely fill the reservoir with water. During continuous operation, the pump overheats and fails faster.

The next important value is the maximum and minimum pressure for the relay to operate. For two-story houses these values ​​are 3 bar and 1.5 bar respectively (Pmax and Pmin). The initial gas pressure in the setting P0=1.3 bar is included in the calculation.

The required volume is determined by the formula: V=16.5 x Qmax x Pmax x Pmin /(a x (Pmax-Pmin)x P0)=16.5x30x3x1.5/(15x(3-1.5)x1.3)=76 l.

The closest in value is a tank with a volume of 80 liters.

A hydraulic accumulator for water supply systems with such a capacity will meet the water supply needs of residents of 2 storey building with three water collection points operating simultaneously.

Do you need extra capacity?

The additional volume of water stored in the hydraulic tank does not affect its operation. The main function of the unit is to maintain pressure in the water supply network.

If a significant supply of water is needed, it is easier and much cheaper to integrate a plastic reserve tank into the system. Therefore, when selecting equipment, it makes no sense to purchase a hydraulic accumulator with a reserve.

When the need for water supply increases, for example, when the number of residents or the amount of water consumed increases household appliances, you can additionally install another small volume hydraulic tank. Their performance is cumulative. The installation location of the additional hydraulic tank does not play an important role.

If necessary, several hydraulic tanks can be installed in the system

Calculation of pressure in the accumulator

In order for the equipment to operate efficiently and meet the needs of the residents of the house, the pressure in the hydraulic tank must be excessive.

In order for water to flow to the upper point of analysis, the air pressure in the cylinder must be greater than the hydrostatic pressure created by a column of liquid with a height from the lower to the upper point of water consumption. For example, for a two-story building this value is equal to P min = 0.7 bar (10 m = 1 bar). Height difference in in this case about 7 m.

For stable operation, a difference of 0.5-0.6 bar is required between the pressures at the lower and upper points.

Thus, the nominal pressure in the accumulator Рnom = 0.6 + 0.7 = 1.3 bar

Factory settings provide the required pressure of 1.5-2 bar, which is optimal for the operation of the accumulator. To monitor it, a tonometer is built into the device.

A tonometer is necessary to monitor the pressure in the hydraulic tank

If the pressure parameter deviates downward, it can be corrected by pumping air car pump, for which a nipple is provided in the device body.

Installation, testing, connection

Simply installing a hydraulic tank is not challenging task– more pressing problem Usually it is a competent choice of volume and operating pressure, so it is better if all the work in the complex is carried out by specialists.

First of all, a location for installation is selected, which must meet the following requirements:

vibration and noise from operating equipment do not disturb residents,

there is sufficient space for maintenance and repair of the hydraulic tank,

reliable support is ensured on a flat and strictly horizontal base.

During installation, shock-absorbing rubber pads are used, which partially dampen vibration.

To install the hydraulic tank, you need a reliable foundation

The hydraulic accumulator is connected to the water supply system in the following order:

Prepare a level area on a solid foundation, for example, concrete floor basement

The hydraulic tank is installed on the base using special gaskets.

Control measurements of pressure in the cylinder are carried out in a non-working state. It must be at least 1.5 bar (atm). This factory setting. If the pressure is insufficient, you can use a car pump.

A fitting with five outlets is installed on the accumulator pipe.

The water pump is connected one by one, water pipe, pressure gauge and pressure switch to the outlets of the fitting.

To reduce vibration, flexible adapters are used. They are installed in the area where the unit is connected to the water supply. Make sure that the adapter's clearance is not less than the diameter of the connected pipe.

Connecting the pump to the hydraulic tank is shown in the video:

The hydraulic tank is filled with water and checked for leaks. If necessary, additional sealing of threaded connections is carried out.

Water must be poured into the tank very slowly to avoid rupture of the membrane. During long-term storage, the “pear” may stick together; with gradual filling, the flexible form will smoothly straighten out.

The power supply is connected and the pressure switch is adjusted according to the instructions for the equipment.

When using a submersible pump, it is necessary to install check valve. It prevents water from flowing back into the well.

Diagram of connecting the hydraulic accumulator to the elements of the water supply network.

Popular models

When purchasing a hydraulic accumulator, the buyer pays main attention to the volume of the cylinder. Today, models with a capacity from 10 liters to 200 liters are produced and used in everyday life.

According to a survey of the Russian Internet audience, the most popular are hydraulic tanks with a volume of 76-100 l, 11-25 l and 26-50. For summer cottages Drives up to 10 liters are often purchased. Vertical installation among the priorities.

Usually, which hydraulic accumulator to buy for water supply systems is chosen simply based on the price-quality ratio. Manufacturers offer models that combine various components and decent quality at a reasonable price. The ranking of manufacturers is as follows: Reflex, Jeelex, Wester, UNIPUMP, CIMM.

Conclusion

A hydraulic accumulator is a necessary element for the water supply system of a private home, which will ensure long-term operation of the pump and uninterrupted water supply. So that the device lasts a long time and does not require frequent repairs, it must be correctly selected and installed correctly, for which it is recommended to use the services of competent specialists. Having figured out what a hydraulic accumulator is needed for, you can plan its installation and look for good specialists who will do everything at the highest level.

A hydraulic accumulator is a special metal sealed container containing inside an elastic membrane and a certain volume of water under a certain pressure.

A hydraulic accumulator (in other words, a membrane tank, hydraulic tank) is used to maintain stable pressure in the water supply system, protects the water pump from premature wear due to frequent activation, and protects the water supply system from possible water hammer. When the power goes out, thanks to the hydraulic accumulator, you will always have a small supply of water.

Here are the main functions that a hydraulic accumulator performs in a water supply system:

1. Protecting the pump from premature wear. Due to the water reserve in the membrane tank, when opening water tap the pump will only turn on if the water supply in the tank runs out. Any pump has a certain rate of starts per hour, therefore, thanks to the hydraulic accumulator, the pump will have a reserve of unused starts, which will increase its service life.
2. Maintaining constant pressure in the water supply system, protecting against changes in water pressure. Due to pressure changes, when several taps are turned on at the same time, sharp fluctuations in water temperature occur, for example in the shower and in the kitchen. The hydraulic accumulator successfully copes with such unpleasant situations.
3. Protection against water hammer, which can occur when the pump is turned on, and can seriously damage the pipeline.
4. Maintaining a supply of water in the system, which allows you to use water even during a power outage, which happens quite often these days. This function is especially valuable in country houses.

Hydraulic accumulator device

The sealed body of this device is divided by a special membrane into two chambers, one of which is intended for water and the other for air.

Water does not come into contact with metal surfaces housing, since it is located in a water chamber-membrane made of strong butyl rubber material, resistant to bacteria and meeting all hygienic and sanitary standards requirements for drinking water.

The air chamber contains a pneumatic valve, the purpose of which is to regulate pressure. Water enters the accumulator through a special threaded connection pipe.

The hydraulic accumulator device must be mounted in such a way that it can be easily disassembled in case of repair or maintenance, without draining all the water from the system.

The diameters of the connecting pipeline and the pressure pipe should, if possible, coincide with each other, then this will avoid unwanted hydraulic losses in the system pipeline.

In the membranes of hydraulic accumulators with a volume of more than 100 liters there is a special valve for bleeding air released from the water. For small-capacity hydraulic accumulators that do not have such a valve, the water supply system must have a device for bleeding air, for example, a tee or tap that shuts off the main line of the water supply system.

IN air valve The hydraulic accumulator pressure should be 1.5-2 atm.

Operating principle of a hydraulic accumulator

A hydraulic accumulator works like this. The pump supplies water under pressure to the accumulator membrane. When the pressure threshold is reached, the relay turns off the pump and water stops flowing. After the pressure begins to drop during water intake, the pump automatically turns on again and supplies water to the accumulator membrane. The larger the volume of the hydraulic tank, the more effective the result of its operation. The response of the pressure switch can be adjusted.

During operation of the accumulator, air dissolved in water gradually accumulates in the membrane, which leads to a decrease in the efficiency of the device. Therefore, it is necessary to carry out preventive maintenance on the hydraulic accumulator by bleeding off the accumulated air. The frequency of maintenance depends on the volume of the hydraulic tank and the frequency of its operation, which is approximately once every 1-3 months.

These devices can be in vertical or horizontal configurations.

The operating principle of the devices is no different, except that vertical hydraulic accumulators with a volume of more than 50 liters have a special valve in the upper part for bleeding air, which gradually accumulates in the water supply system during operation. Air accumulates in the upper part of the device, therefore the location of the valve for bleeding is chosen in the upper part.

In horizontal devices for bleeding air, a special tap or drain is mounted, which is installed behind the hydraulic accumulator.

From small devices, regardless of whether they are vertical or horizontal, air is released by completely draining the water.

When choosing the shape of a hydraulic tank, proceed from the size of the technical room where they will be installed. It all depends on the dimensions of the device: whichever fits best into the space allocated for it will be installed, regardless of whether it is horizontal or vertical.

Connection diagram for hydraulic accumulator

Depending on the assigned functions, the connection diagram of the hydraulic accumulator to the water supply system may be different. The most popular connection diagrams for hydraulic accumulators are given below.

Such pumping stations are installed where there is high water consumption. As a rule, one of the pumps at such stations operates constantly.
At the booster pumping station, the hydraulic accumulator serves to reduce pressure surges when additional pumps are turned on and to compensate for small water withdrawals.

This scheme is also widely used when the water supply system frequently interrupts the supply of electricity to booster pumps, and the presence of water is vital. Then the water supply in the hydraulic accumulator saves the situation, playing the role backup source for this period.

The larger and more powerful the pumping station, and the greater the pressure it must maintain, the larger the volume of the hydraulic accumulator, which acts as a damper, must be.
Buffer capacity The hydraulic tank also depends on the volume of the required water supply, and on the difference in pressure when the pump is turned on and off.

For long-term and uninterrupted operation, the submersible pump must make from 5 to 20 starts per hour, which is indicated in its technical characteristics.

If the pressure in the water supply system drops to minimum value The pressure switch is automatically turned on, and at the maximum value it is turned off. Even the most minimal water flow, especially in small water supply systems, can reduce the pressure to a minimum, which will instantly give a command to turn on the pump, because the water leakage is compensated by the pump instantly, and after a few seconds, when the water supply is replenished, the relay will turn off the pump. Thus, with minimal water consumption, the pump will run almost idle. This mode of operation adversely affects the operation of the pump and can quickly damage it. The situation can be corrected by a hydraulic accumulator, which always has the required supply of water and successfully compensates for its insignificant consumption, and also protects the pump from frequent activation.

In addition, a hydraulic accumulator connected to the circuit smoothes out a sharp increase in pressure in the system when the submersible pump is turned on.

The volume of the hydraulic tank is selected depending on the frequency of activation and power of the pump, water flow per hour and the height of its installation.

For storage water heater in the connection diagram the hydraulic accumulator plays a role expansion tank. When heated, water expands, increasing the volume in the water supply system, and since it does not have the ability to compress, the slightest increase in volume in a confined space increases the pressure and can lead to destruction of the water heater elements. The hydraulic tank will also come to the rescue here. Its volume will directly depend and increase from an increase in the volume of water in the water heater, an increase in the temperature of the heated water and an increase in the maximum permissible pressure in the water supply system.

The hydraulic accumulator is connected in front of the booster pump along the water flow. It is needed to protect against a sharp decrease in pressure in the water supply network when the pump is turned on.

The capacity of the hydraulic accumulator for the pumping station will be greater, the more water is used in the water supply system and the smaller the difference between the upper and lower pressure scale in the water supply in front of the pump.

How to install a hydraulic accumulator?

From all of the above, it can be understood that the design of a hydraulic accumulator is absolutely different from an ordinary water tank. This device is constantly in operation, the membrane is always dynamic. Therefore, installing a hydraulic accumulator is not so simple. The tank must be strengthened during installation reliably, with a margin of safety, noise and vibration. Therefore, the tank is secured to the floor through rubber gaskets, and to the pipeline through rubber flexible adapters. You need to know that at the inlet of the hydraulic system, the cross-section of the line should not narrow. And another one important detail: the first time you fill the tank very carefully and slowly, using weak pressure water, in case the rubber bulb has stuck together due to long inactivity, and with a sharp pressure of water it may be damaged. It is best to remove all air from the bulb before putting it into use.

The hydraulic accumulator must be installed in such a way that it can be easily approached during operation. It is better to entrust this task to experienced specialists, since very often the tank fails due to some unaccounted for, but important little detail, for example, due to a mismatch in pipe diameter, unregulated pressure, etc. Experiments cannot be carried out here, because the normal operation of the plumbing system is at stake.

So you brought the purchased hydraulic tank into the house. What to do with it next? You immediately need to find out the pressure level inside the tank. Usually the manufacturer pumps it up to 1.5 atm, but there are cases when, due to a leak, the performance drops by the time of sale. To make sure the indicator is correct, you need to unscrew the decorative cap on an ordinary automobile spool and check the pressure.

How can I check it? Typically a pressure gauge is used for this. It can be electronic, mechanical automotive (with a metal body) or plastic, which comes complete with some pump models. It is important that the pressure gauge has greater accuracy, since even 0.5 atm changes the quality of the hydraulic tank, so it is better not to use plastic pressure gauges, as they give a very large error in the indicators. These are usually Chinese models in a weak plastic case. On indicators electronic pressure gauges affected by battery charge and temperature, in addition, they are very expensive. That's why the best option is an ordinary car pressure gauge, verified. The scale should have a small number of divisions to allow more accurate pressure measurements. If the scale is designed for 20 atm, but you only need to measure 1-2 atm, then high precision there is no need to expect.

If there is less air in the tank, then there is a larger supply of water, but the difference in pressure between an empty and almost full tank will be very significant. It's all a matter of preference. If you need constant high water pressure in the water supply, then the pressure in the tank must be at least 1.5 atm. And for domestic needs, 1 atm may well be enough.

At a pressure of 1.5 atm, the hydraulic tank has a smaller supply of water, which is why the booster pump will turn on more often, and in the absence of light, the supply of water in the tank may simply not be enough. In the second case, you will have to sacrifice pressure, because you can take a shower with a massage when the tank is full, and as it empties, you can only take a bath.

When you decide what is more important to you, you can set the desired operating mode, that is, either pump air into the tank or bleed off excess air.

It is undesirable to reduce the pressure below 1 atm, as well as to exceed it excessively. A bulb filled with water with insufficient pressure will touch the walls of the tank and can quickly become unusable. And excess pressure will not allow pumping in a sufficient volume of water, since most of the tank will be occupied by air.

Setting up the pressure switch

You also need to configure the pressure switch. Opening the cover, you will see two nuts and two springs: a large one (P) and a small one (delta P). With their help, you can set the maximum and minimum pressure levels at which the pump turns on and off. A large spring is responsible for turning on the pump and pressure. You can see from the design that it seems to encourage water to close the contacts.

Using a small spring, the pressure difference is set, which is specified in all instructions. But the instructions do not indicate a starting point. It turns out that the reference point is the spring nut P, ​​that is, the lower limit. The lower spring, responsible for the pressure difference, resists the water pressure and moves the movable plate away from the contacts.

When the correct air pressure has already been set, you can connect the accumulator to the system. After connecting it, you need to carefully observe the pressure gauge. All hydraulic accumulators indicate normal and maximum pressure values, exceeding which is unacceptable. Manual disconnection of the pump from the network occurs when the normal pressure of the accumulator is reached, when the limit value of the pump pressure is reached. This occurs when the increase in pressure stops.

The pump power is usually not enough to pump the tank to the limit, but this is not even particularly necessary, because when pumping, the service life of both the pump and the bulb is reduced. Most often, the pressure limit for switching off is set 1-2 atm higher than switching on.

For example, when the pressure gauge reads 3 atm, which is sufficient for the needs of the owner of the pumping station, you need to turn off the pump and slowly rotate the nut of the small spring (delta P) to decrease until the mechanism is activated. After this, you need to open the tap and drain the water from the system. While observing the pressure gauge, you need to note the value at which the relay turns on - this is the lower pressure limit when the pump turns on. This indicator should be slightly higher than the pressure in an empty accumulator (by 0.1-0.3 atm). This will make it possible to serve the pear for a longer period of time.

When the nut of the large spring P rotates, the lower limit is set. To do this, you need to turn on the pump and wait until the pressure reaches the desired level. After this, it is necessary to adjust the nut of the small spring “delta P” and complete the adjustment of the accumulator.

In the air chamber of the accumulator, the pressure should be 10% lower than the pressure when the pump is turned on.

An accurate indicator of air pressure can only be measured with the tank disconnected from the water supply system and in the absence of water pressure. Air pressure must be constantly monitored and adjusted as necessary, which will increase the life of the membrane. Also, to continue the normal functioning of the membrane, a large pressure drop should not be allowed when the pump is turned on and off. A normal difference is 1.0-1.5 atm. Stronger pressure drops reduce the service life of the membrane, greatly stretching it; moreover, such pressure drops do not allow comfortable use of water.

Hydraulic accumulators can be installed in places with low humidity, not subject to flooding, so that the flange of the device can successfully serve for many years.

When choosing a brand of hydraulic accumulator, you need to pay attention Special attention check the quality of the material from which the membrane is made, check certificates and sanitary and hygienic conclusions, making sure that the hydraulic tank is intended for systems with drinking water. You also need to make sure that there are spare flanges and membranes, which should be included in the kit, so that in case of a problem you do not have to buy a new hydraulic tank.

The maximum pressure of the hydraulic accumulator for which it is designed must be no less than maximum pressure in the water supply system. Therefore, most devices can withstand a pressure of 10 atm.

To determine how much water can be used from the accumulator when the power is turned off and the pump stops pumping water from the water supply system, you can use the occupancy table membrane tank. The water supply will depend on the setting of the pressure switch. The higher the pressure difference when turning the pump on and off, the greater the supply of water in the accumulator. But this difference is limited for the reasons stated above. Let's look at the table.

Here we see that in a membrane tank with a volume of 200 liters, with the settings of the pressure switch, when the indicator on the pump is 1.5 bar, the pump off is 3.0 bar, the air pressure is 1.3 bar, the water supply will be only 69 liters, which is equal to approximately a third of the total volume of the tank .

Calculation of the required volume of the hydraulic accumulator

To calculate the accumulator, use the following formula:

Vt = K * A max * ((Pmax+1) * (Pmin +1)) / (Pmax- Pmin) * (Pair + 1),

• Amax – maximum flow rate of liters of water per minute;
• K is a coefficient that depends on the power of the pump motor;
• Pmax – pressure when the pump is turned off, bar;
• Pmin – pressure when the pump is turned on, bar;
• Pair. – air pressure in the hydraulic accumulator, bar.

As an example, let’s select the required minimum volume of a hydraulic accumulator for a water supply system, taking, for example, the Aquarius BTsPE 0.5-40 U pump with the following parameters:

Using the formula, we calculate the minimum volume of HA, which is 31.41 liters.

Therefore, we choose the next closest GA size, which is 35 liters.

Tank volume in the range of 25-50 liters is ideally consistent with all methods for calculating the volume of HA for household plumbing systems, as well as with empirical assignments different manufacturers pumping equipment.

If there are frequent power outages, it is advisable to choose a tank of a larger volume, but at the same time you should remember that water can only fill the tank by 1/3 of the total volume. The more powerful the pump installed in the system, the larger the volume of the accumulator should be. This sizing will reduce the number of short starts of the pump and extend the life of its electric motor.

If you bought a large-volume hydraulic accumulator, you need to know that if water is not used regularly, it will stagnate in the hydraulic accumulator and its quality will deteriorate. Therefore, when choosing a hydraulic tank in a store, you need to take into account the maximum volume of water used in the home’s water supply system. After all, with a small water consumption, using a tank with a volume of 25-50 liters is much more expedient than 100-200 liters, the water in which will be wasted.

Repair and maintenance of hydraulic accumulator

Even the simplest hydraulic tanks require attention and care, like any working and useful device.

There are different reasons for repairing a hydraulic accumulator. This is corrosion, dents in the body, violation of the integrity of the membrane or a violation of the tightness of the tank. There are also many other reasons that oblige the owner to repair the hydraulic tank. To prevent serious damage, it is necessary to regularly inspect the surface of the accumulator and monitor its operation in order to prevent possible problems. It is not enough to inspect the HA twice a year, as stated in the instructions. After all, you can eliminate one malfunction today, but tomorrow you will not pay attention to another problem that has arisen, which within six months will turn into irreparable and can lead to failure of the hydraulic tank. Therefore, the hydraulic accumulator must be inspected at every opportunity so as not to miss the slightest malfunctions, and they must be repaired in a timely manner.

Causes of breakdowns and their elimination

The reason for the breakdown of the expansion tank may be too frequent switching on and off of the pump, water exiting through the valve, weak water pressure, weak air pressure (lower than designed), weak water pressure after the pump.

How to troubleshoot a hydraulic accumulator with your own hands? The reason for repairing the hydraulic accumulator may be low air pressure or its absence in the membrane tank, damage to the membrane, damage to the housing, a large difference in pressure when turning the pump on and off, or an incorrectly selected volume of the hydraulic tank.

Troubleshooting can be done as follows:

• to increase air pressure, you need to pump it through the tank nipple using a garage pump or compressor;
• a damaged membrane can be repaired at a service center;
• the damaged housing and its tightness are also repaired at the service center;
• The difference in pressure can be corrected by setting the differential too large in accordance with the frequency of pump activation;
• The adequacy of the tank volume must be determined before installing it in the system.

If you have come to this page, then most likely you are looking for which hydraulic accumulator to choose for the water supply system of your private home. If this is the case, then sit back and we will look into this issue together.

To make the topic easier to understand, we have divided it into several sections:

First, let's figure out why a membrane-type expansion tank is needed: first of all, to smooth out hydraulic shocks when the pump is turned on.

Water hammer- this is an instantaneous pressure jump in the pipe at sudden change speed of water flow.

Secondly, together with the automation system, it allows you to maintain constant pressure in the home water supply system.

And thirdly, the hydraulic tank can be used to accumulate a supply of water, which is especially important for low-yield wells during peak water consumption, when we simultaneously wash, wash, and go to the toilet. And the power of the well is not enough to ensure such a flow of water, this is what the hydraulic accumulator is used for, water will be consumed from it, and then it will be slowly recharged from the well, for example, at night.

Which color should you choose: red or blue?

Expansion tanks come in blue and red colors, blue ones are hydraulic accumulators, and red ones are expansion tanks for heating systems. Reds, by internal structure slightly different from the blue ones.

Types and sizes of hydraulic accumulators

Hydraulic accumulators are made vertical and horizontal view. It all depends on where the hydraulic tank is installed.

There are different sizes, the size of the membrane tank is determined by the power of the engine and the power of the well. The more powerful the well, the smaller the hydraulic accumulator you can buy.

What is it made of?

Hydraulic accumulator from of stainless steel

Membrane tanks for water supply systems consist of: a body - made of high-tech alloy and covered with enamel. But there are also more expensive options - a stainless steel hydraulic accumulator. Inside the case there is a rubber membrane, which is a rubber bag, which also comes in different qualities.

Ask the seller to disassemble the housing to evaluate the quality of the membrane!

A nipple is also screwed into the tank, and more expensive models have a pressure gauge.

Hydraulic accumulator device for water supply

Operating principle of a hydraulic accumulator.

Air is pumped through the nipple between the housing and the membrane. When the well pump is turned on, water enters the membrane and fills it to a certain pressure, which is regulated automatically and the pump turns off. When we open the tap to wash our hands, for example, compressed air between the tank and the membrane begins to squeeze water out of the membrane, thereby creating pressure in the water supply system of the house. When the pressure drops to a critical level, the automation turns on the pump again and fills the accumulator.

What are the storage tank sizes?

When choosing an expansion tank for water supply, you should know that at operating pressure in the accumulator, when the pump is turned off, it contains only 40% of the water of its total volume. Those. if the tank is 100 liters, then there will be only 40 liters of water in it.

The most popular models are in the range from 20 to 500 liters.

What volume of hydraulic accumulator should I choose?

Let's talk about what volume of hydraulic accumulator to choose that is right for you. There is a special formula for this that can be used to calculate the required tank volume.

• Amax - estimated maximum water flow (liter/min)
• K - coefficient is selected depending on the electrical power of the pump, see table

• Pmax - pump switch-off pressure, bar
• Pmin - pump activation pressure, bar
• Pair. - pressure in the air cavity of the hydraulic tank, bar

For example, let’s take a water supply system built on an Aquarius BTsPE 0.5-50 pump with the following data:

Pmax = 3.0 bar

Pmin = 1.7 bar

Pair. = 1.5 bar

Amax = 2.1 m3/h (35 l/min)

K = 0.25 (from the table above, since the pump power is 970 W)

From the calculation using the formula, we obtain the value V = 29.1 liters

The tank with the closest volume is 35 liters, select it for purchase.

Prevention and repair.

In general, hydraulic accumulators should be checked every six months. And you should check: the membrane, whether it is torn, and the air pressure between the membrane and the tank.

It should be remembered that a faulty hydraulic tank does not provide protection against water hammer. And when a water hammer occurs, the entire room where the water supply system is installed is flooded.

You can check the air pressure in the tank with a pressure gauge, which is installed on the car pump; we connect it to the tank nipple, just like to the car wheel. But before this, it is necessary to drain all the water from the tank, disconnect the pump from the power supply, and then take measurements and, if necessary, create the required pressure.

The air pressure in the accumulator should be 10% lower than the pressure at which the pump turns on. For example, if the pump starts at a water pressure of 1.6 bar, then the air pressure in the tank should be 1.4 bar. At this air pressure, a minimum amount of water remains in the expansion tank.

When should you check the air pressure in the hydraulic tank? If you use the water supply system only during the warm season, then the pressure should be checked before the start of the season. And if the system is used year-round, then the pressure should be checked 2-3 times a year.

The repair is very simple: unscrew the cap on the tank, remove the damaged rubber membrane, install a new membrane and put everything back together in the reverse order. Then use a car pump or compressor to create pressure in the cavity between the tank and the membrane.