We tell you what a water return valve is as arranged, we consider the characteristics of different types of devices.
Check valve is required for autonomous water supply. Put it in high-rise buildings with centralized water supply. The reinforcement device ensures uninterrupted operation of the system, prevents emergency situations. We analyze the types of return valves for water, their design and principle of operation.
All about the check valve
What it isDevice of the reinforcement node
How does he work
Valve Valve Frames
- Spring
- Rotary
- Lifting
- Sharied
What it is
The return valve refers to the devices of shut-off valves. It is designed to protect the water-based system from changes in water flow parameters: lowering or increase pressure, leaks. The reinforcement node stops the liquid, does not give it to advance in the opposite direction. It protects plumbing devices and a highway from a hydraulic impact.
These are the main reasons why the return valve for water is needed. Put it on different sites. We list the possible installation options.
- In the well or well in front of the submersible pump. This prevents draining water after stopping the equipment and does not give the pump to work "on dry".
- At the inlet of the pumping station.
- After the meter-water meter. This will protect the device from the hydrowards, which are possible when using faulty plumbing.
- In the offline heating system with multiple contours with different pressure.
- Before plumbing devices.
If the valve is mounted in a temporary accommodation house, for example, in the country, it is necessary to provide a liquid drainage. Otherwise, when cooling up to minus marks, the highway will penetrate, and the valve fails.
How the check valve is arranged
We produce several types of production valves, but they are arranged all according to one principle. The main element is the collapsible body, most often cylindrical shape. It consists of a reception area that is connected to the pipe, the limiter of any type, the mechanism locking this limiter, and the output zone, which is also connected to the pipeline.
For the manufacture of cabinet parts, different materials are used. It can be bronze, brass, various forks of steel, high-strength plastic, titanium or cast iron. For household appliances, the most preferably brass. It costs relatively inexpensive, but it serves a long time. Inside the case installed a shut-off element. To ensure that it necessary for normal operation, tightness is used by seals. They can be made of plastic, rubber rubber or made by moving a thin layer of stainless steel.
How fittings work
We'll figure it out how the check valve works. There is nothing difficult in this. While the flow inside the device is absent, the shut-off element is hermetically overlaps the pipe. As soon as the valve opens, and water begins to move into the housing, the pressure of the liquid turns the mechanism and shifts the constipation. All the time, while the pressure is high enough, the shut-off element is held in the open position.
During normal operation of the reinforcement, water under pressure flows in a given direction. It is indicated on the arrow instrument housing. When the pressure drops to minimum values or the flow changes the focus and tries to flow back, the mechanism works, and the constipation falls into the opening of the case. It completely overlaps the fluid movement. Thus, the valve interferes with the flow to move in the opposite direction and maintains normal pressure inside the system.
Varieties of fittings
On sale you can find several varieties of production valves. The principle of their action is the same, the difference in the design. Briefly describe each type.Spring
It is considered the most compact species. It can be disk or bivalve. In the first case, the constipation serves a plate disc from metal. Spring it tightly presses to the saddle. In this position, the path for the liquid is closed. The aqueous stream presses the spring and raises the disk. Under reduced pressure, the valve closes. This is the simplest scheme that works well in water supply systems, where it is impossible to hydrate.
If there is a probability of hydraulic impact, double-minded structures. They are the same as a disc, but shut-off element, opening the hole for the liquid, folds in half. This mitigates the effects of the hydraulic man. There are models of bivalve valves with special shock absorbers. They are installed in complex hydraulic systems.
The main advantages of spring devices are considered compactness and a small weight. Particularly compact interflace models that do not need special flanges to secure to the pipeline. Spring systems are very easy to operate and install, can be installed on horizontal, inclined and vertical highways. Significant drawback - they need to be completely removed for repair.
Turning
The constipation in this design serves as a spool petal. It is attached to the swivel axis, which is located above the passing hole. The stream leans the spool and opens a passage through the pipeline. In case of insufficient pressure, the petal falls and overlaps the hole. If the diameter of the part is large, the shock of the planting space is very strong. This contributes to the rapid wear of the reinforcement and can provoke hydrowards.
For this reason, the model of large sizes are produced in unstable performance. They are equipped with an additional mechanism that gently puts a spool in place. For small devices, such devices are not needed.
The main advantage of turning systems is low sensitivity to the level of pollution of the fluid supplied through them at good tightness. In addition, they can work in large-sized pipelines. True, in this case, only unstressed models are used.
Lifting
In this design, the passing hole overlaps the lifting disk-spool. Water stream moving under a certain pressure raises it. When pressure decreases, the shutter is lowered down, rises on its seat and overlaps the hole.
The axis where the disk is attached is located so that the normal valve operation is possible only in exactly a vertical position. Therefore, it cannot be installed even on inclined, and even more so horizontal pipelines. This is an important feature of the lifting design.
Its main advantage is the ability to repair without dismantling. Cleaning and repair work is carried out through a special hatcher with a removable lid. Significant lack of lifting devices is considered sensitivity to the level of contamination passing through them.
Ball
A metal ball is used as a shut-off element. Sometimes it is covered with a layer of rubber for better fit to the landing place. The ball is spring-loaded, therefore, the liquid is not served, it overlaps the passage hole. The flow presses on the spring and shifts it with the ball. When a pressure drop or redirect flow, the spring-loaded ball overlaps the fluid passage.
This is a very simple and reliable design. It can work in horizontal, inclined or vertical pipes. It is universal, used for different engineering systems. Some models are equipped with a lid so that they can be cleaned and repair without dismantling.
Varieties by installation method
Regardless of the design, the armature varies with the installation method. There may be four options.
- Flange type mount. The device is attached to the pipeline using flanges with a mandatory seal.
- Welding. The node is welded to pipe segments. This is the most reliable type of fastening, is required for details operating in aggressive environments.
- Interflant fasteners. The valve does not have fasteners. It is securely clamped between the flanges fixed on the pipes. This embodiment has limitations on dimensions. For details of large diameter, it is not used.
- Fastening a coupling type. The device is equipped with threaded couplings with which it is attached to the pipes. It is undesirable to use such fasteners for products of large diameter.
We figured out how it works and what the return valve for water looks like. It is necessary to choose the device taking into account the passage diameter of the highway, the pressure in it and the degree of contamination of the undergoing flow. In addition, you need to choose a place and method of consolidation. Typically take fasteners of this type, which is already used on the highway. Given the wide range of reinforcement in specialized stores, finding the appropriate option will be easy.
