Solenoid solenoid valve: where used + types and principle of operation

In addition to the usual manual valves in the store you can also see the solenoid solenoid valve of automatic action. It allows not only to control the flow of liquids and gases in pipelines at a distance, but also to automate this process.

Such devices differ in their internal design and purpose. However, the principle of operation is the same for all of them - closing / opening of the crane occurs due to the operation of the electromagnet.

In this article, we will consider why such a valve is needed and how it works. We also talk about the main varieties of solenoid solenoid valves.

Why is a solenoid valve needed?

Solenoid valves are a category of modern valves for pipelines of various purposes. In everyday life, such electrovalves are used in automobiles, special equipment, water supply systems and automatic watering and heating systems.

They are also widely used in industry to control current and control the transport of a variety of liquids and gases.

A solenoid solenoid valve refers to volatile equipment, it needs power supply to operate on opening or closing

Inside the electromagnetic valve for water or gas does not have any sensors. With its help, you can only regulate or completely block the flow of the working environment. If automation of these processes is required, then additional measuring devices will have to be installed, tying the operation of the electrovalve already on them.

For example, use an additional controller and water leakage sensorso that at the time of detection of a leak, the solenoid valve receives an appropriate command from the controller and shuts off the pipeline.

Among the advantages of using solenoid valves are:

• quick adjustment of the working fluid current through the pipeline;
• universality and reliability of the device;
• long term of operation;
• small size and light weight;
• variety of varieties of the device.

Actuation of the valve occurs literally in a split second after the signal is applied to it. It is designed to work with liquids under different pressures, from 0 to 25 bar, and with a changing temperature, from -20 to +120 ° С. Moreover, in the de-energized state, such an electrovalve can remain both in the closed position and open - it all depends on the modification of the device.

Most often in everyday life, a solenoid solenoid valve is used in water supply and heating systems, where it can be used to remotely control the water flow.

In water supply systems, it allows you to automatically shut off the water supply when a pipe rupture. And in heating systems, such a valve is used as a device for regulating the flow of coolant.

Here, by an external temperature sensor, it independently reduces or increases the current of heated liquid from the boiler to the radiators.

How does a valve with a solenoid work?

The solenoid solenoid valve consists of:

• steel, cast-iron, brass or polymer bodies;
• core induction coil (solenoid);
• working locking element;
• sealant;
• damping spring.

The induction coil made of copper inside the shut-off device is located in a sealed enclosure where water is not accessible. The overlapping or opening of the current channel of the working medium occurs due to the rod and membrane that is extended by the action of the solenoid.

The power supply to the solenoid valve is connected via the terminals on the top of the device housing next to the induction coil

In a de-energized state, under the influence of a spring, the valve completely blocks the current channel or leaves it completely open. Further, after applying voltage to the coil, the core moves with the rod, as a result of which the cross section of this duct increases / decreases.

The general principle of operation of the electromagnetic valve in question is simple - the movement of the rod occurs in it due to electromagnetic induction. When an electric current flows through the coil, an electromagnetic field acts on the core located in its center, the strength and direction of which depend on the applied voltage in volts.

As a result, the locking element is displaced and the valve bore is changed.

The solenoid valve coil, depending on the modification of the device, can operate on a voltage of 5–36 V DC or 220 V AC

Solenoid valves with a low control voltage are designed for operation in pipelines of small diameter and with a low pressure of the working medium. The scope of their application is quite limited.

But such valves are easier to integrate into the control system on low-voltage semiconductor devices and connect to various microcontrollers. In water pipes and heating circuits of private houses, they are usually used.

Varieties of solenoid solenoid valves

There are several varieties of the device in question. Such devices are classified according to the material of manufacture of the case, design and the position in the de-energized state of the constipation inside, the type of seal and the method of connection to the pipes.

Each of these options is designed to work with a specific environment in terms of composition, temperature and pressure. Select the solenoid solenoid valve carefully. If you take an inappropriate device, it will not last long.

The first and main division of electromagnetic valves is according to the type of electric current. So, they can work from alternating or direct current

By the method of connection, the solenoid solenoid valves are divided into:

• flanged;
• coupling;
• nipple.

And in size, they can be from 6 to 150 DN (from 1/8 to 6 inches). There is an option for any pipeline.

The body of the considered electrovalves is made of:

• plastic (reinforced PPA, PVC, nylon);
• of stainless steel;
• brass;
• cast iron.

Each of these options has its own characteristics in terms of pressure and temperature of the medium.These figures should be carefully studied in the instrument passport so as not to make a mistake with the choice. At the same time, any of the above variations is suitable for plumbing or heating in a private house.

Classification # 1 - Internal

Valves by the design of the control element are divided into three groups:

1. Zolotnikovye.
2. Membrane
3. Piston

Household solenoid valves are usually made with a diaphragm. This is a cheap and reliable option that can cope with the regulation of water flow in domestic heating and water supply systems without any problems.

The internal elements - spring, plunger and core, are almost always made of stainless steel, which is highly resistant to changes in temperature and water pressure

The main separation of the solenoid valves is carried out by the position of the locking mechanism with a de-energized electromagnet.

According to this parameter, the solenoid solenoid valves are divided into:

• normally closed, valve closed (NC);
• normally open, valve open (BUT);
• bistable.

In the first case, until the voltage is applied to the solenoid, the core is lowered by the pressure of the spring and there is no water flow. In the second case, when the device is de-energized, the channel, on the contrary, is fully open, and it closes only after power is supplied.

The third option - the position can be either open or closed.

Classification # 2 - on the principle of functioning

Functionally solenoidal electric valves for water at 220 V and other voltages are:

• one-way;
• two-way;
• three-way.

The first have only one pipe connection to the pipeline. it safety devicesdesigned to release steam or water at too high pressure in the pipes.

Two-way solenoid valves are the most common and in demand. They have two nozzles - inlet and outlet, and are installed in the gap of the pipeline

Three-way devices come with three nozzles for connecting to pipes. Such options are designed to redirect the flow from one pipeline to another.

Most widely three way valves used in heating systems. Such devices make it easy to transfer the coolant from one circuit to another to mix the working environment.

As a result, the water temperature in the system changes, and the heat source continues to work without changing the mode.

Also, electromagnetic valves are:

• direct action;
• indirect action.

In the first, the core moves exclusively under the influence of an electromagnet. Secondly, the pressure of the working medium also affects its movement.

Classification # 3 - by sealant and membrane material

A membrane is located inside the solenoid valve body, which blocks the flow of water. Plus, between the coil and the main pipe with a seal is located. Both of these elements are made of flexible polymeric materials.

Most often, in household solenoid valves for water, seals and membranes are made of EPDM, which is highly resistant to salts and low temperatures

The seal in the solenoid valves can be made of:

• FPM (FKM, VITON) - fluoroelastomer;
• EPDM - ethylene propylene elastomer;
• NBR - nitrile butadiene rubber.

The first option is characterized by a high maximum temperature of the working environment and resistance to oils and gasolines. The second is cheap and resistant to salts, alkalis and acids dissolved in water. The third - quietly tolerates contact with petroleum products, usually used in industry and automobiles.

This material does not greatly affect the price of the solenoid valve. Details of it are too small in size. The type of sealant and membrane should be selected solely on the basis of the characteristics of the medium.

The thermal properties of the seals are presented in the following table:

In this case, in any case, special attention when operating the electrovalve should be given to the absence of impurities in the water.

Sand and rust in the pipes sooner or later spoil any membrane, regardless of the material of its execution. The device in question can only be installed if there is a filter in the pipeline.

Conclusions and useful video on the topic

Solenoid Valve Device Overview:

How the solenoid valve for 220 V direct operation is arranged and operates:

Types of solenoid valves according to the principle of operation:

The remote control solenoid valve is unpretentious and reliable. It is designed for several tens of thousands of operations (it will work properly for 20–25 years) and does not require specialized maintenance.

Such a device costs under water within 3-6 thousand rubles, but it helps to solve many problems. At the same time, it is not difficult to mount it on your own, you just need to correctly select a similar valve according to its characteristics and materials.

Do you want to supplement the above material with useful information or point out a discrepancy or error? Or want to give recommendations on choosing the optimal model of a solenoid solenoid valve? Please write your advice and comments in the comments section.

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