Control valves are an essential component in modern water supply systems. There are different groups of such devices, each of which is responsible for certain parameters of infrastructure management. One of the key places in the functionality of this regulation is occupied by a water reducer - a compact device designed to control pressure indicators.
The main tasks of the device
Normalization of pressure indicators in the water supply system is the main purpose of this device. The pressure reducing valve performs pressure increase and decrease operations on a specific section of the pipeline, based on current operating requirements. As for the application areas, in most cases, such regulation is carried out at the installation sites of sanitary fittings and other functional devices involved in the flow control processes. For example, a household water pressure reducer in a water supply system can be installed on circuits where air vents, manometers, flow sensors, etc. are also used.
Moreover, not only water, but also gas-air mixtures, special compositions of coolants and antifreeze can act as a working medium. Another thing is that in each case a device with appropriate protective properties is required. In terms of protection of the gearbox, it is important to consider its ability to withstand temperature extremes, mechanical loads and chemical influences when it comes to coolants with special additives.
Water Gear Design
The device is a type of valve mechanism, including a drive, a setter and a plate, unloaded from hydrostatic forces. Sensitive elements for regulation may vary, which will be discussed separately. Flange fittings are used for connection, and fluoroplastic o-rings are responsible for sealing, although there are also so-called solid gearboxes, the design of which is dispensed with without seals. The main material for the manufacture of a water reducer is metal, represented by cast iron or carbon stainless steel. Secondary parts and consumables can be made of composite materials, polyester fabric and other synthetics.
Principle of operation of a piston gearbox
The working mechanism is represented by a spring-loaded piston, which allows you to increase or decrease the pressure in the system. The force of the spring itself is affected by a special valve controlled via a drive or manually. Low throughput limits the scope of piston water pressure reducers. In an apartment, for example, in this way it is possible to serve flows up to 1.5-2 m 3 / h. At the same time, in order to prevent clogging, it is recommended to give preference to models with a built-in filter.
From the point of view of the principle of regulation, it is possible to distinguish between static and dynamic piston gearboxes. In the first case, the calculation is made for uneven water consumption with constant pressure adjustment. Such systems are installed at the entrances of water supply systems to private houses or apartments. Static models, in turn, work in conditions of constant flow support with approximately the same power. Activation of the device is required only in rare cases when changing the operating conditions of the working medium or changing the temperature of the water.
Principle of operation of a water reducer with a membrane
A spring is also used as a force regulating element, however, its action is directed to the surface of the membrane acting as a valve. In order to eliminate clogging, which may be critical to the membrane, the regulating mechanics are enclosed in a sealed chamber. Damping cameras also help minimize the effects of network vibrations on the sensitive element of the controller.
Due to structural optimization, a water reducer of this type is capable of providing a flow rate of up to 3 m 3 / h, which is a good indicator in the context of domestic use. In general, they are unpretentious in maintenance and universal in terms of applications, and also have a high service life.
Features of flow reducers
Designs with a minimum number of movable parts, which determines their durability. Regulation is carried out due to the displacement of flows through different channels. At the heart of such a gearbox is a network of small separated water movement circuits. This configuration can be compared with labyrinths that impede the passage of the coolant. Thus, if necessary, the flow rate is reduced and, accordingly, the pressure indicator is reduced. As a rule, flow-type household water reducers are used in irrigation systems at the output section of an additional regulator.
Gearbox installation
For most gearboxes, the installation position is not critical. However, in order to achieve an effective regulatory function, it is desirable to determine in advance the most advantageous placement point on the flow line. For example, if you plan to install the device above the boiler or boiler, then the pressure readings will be incorrect due to the heating of water in this area. This factor will affect the operation of the regulator.
In addition, the device of the water reducer with a membrane is sensitive to temperature differences, which will also distort the control parameters. Directly during installation, the flow vector is also taken into account. Typically, the arrow indicates the direction of water movement on the device’s body. Installation is carried out with the help of complete sanitary fittings, and on both sides of the installation site it will not be out of place to make a tie-in and ball valves to ensure the possibility of dismantling the gearbox without blocking the water in the central highway.
Pressure regulation process
The gearbox can be adjusted already after installation - especially since during the installation process the set pressure indicator can be lost. The unit for setting the operating mode, as a rule, is closed with a protective cap. It must be removed by allowing access to the pressure disk. Through it, the water reducer is adjusted, which will help the hex key. The disk is rotated to the desired division with a pressure indicator. It should be borne in mind that the setting should be performed only when the water supply is disconnected from the points of intake. Again, if ball valves were provided, then before adjusting it will be enough to block only them.
Conclusion
Differential pressure in water supply and heating systems is a natural phenomenon and does not pose a serious threat if you keep the load under control. Otherwise, there will be a risk of water hammer, which can lead to equipment malfunctions, not to mention the risks of accidents in the pipeline itself. But this applies only to rare cases. Not every system (especially household) requires the arrangement of a special regulatory unit for such purposes, but if, in principle, high loads are noted due to the operation of powerful circulating equipment, then it is advisable to insure yourself.
A standard water pressure reducer in a water supply system does not take up much space and does not interfere with the operation of other adjusting devices. In terms of financial costs, it will not become a burden either - a decent-quality model can be purchased for 1-1.5 thousand rubles. Experts recommend paying attention to the model lines of VALTEC, Watts and others. By the way, some versions of heating and pumping equipment include gearboxes as standard. But, as practice shows, the presence of a separate device for monitoring pressure indicators is a more reliable solution to the problem. In systems where it is planned to control several long lines of water circulation, such a configuration with separate gearboxes is completely possible.