Ball check valve: description, characteristics, device and reviews

The creators of pipeline systems expected that water or any other product would move in one direction. But practice shows that there are exceptions. In order to avoid emergency situations, if the flow goes the other way, a non-return valve or one of its varieties - a ball valve - is used in the pipelines. Consider the device and the principle of operation of the non - return valve and, in particular, the ball elements. We also learn how to choose the right device.

Device

A typical ball valve is a cylinder, inside of which is a spring and a locking device. In our case this is a ball. In other types of mechanisms a plate can be used. In the basic assembly, the valve is in the closed state due to the spring located inside. However, under the influence of the flow, this part can reduce the pressure force, and the valve will open. The flow will go through it. If the pressure drops (and this can happen due to leaks, shutdown of the pumping system or for other reasons), then the spring mechanism closes the locking mechanism. If the head moves toward the valve, then, due to the locking element, the liquid can not pass.

Types of mechanisms

In today's market, you can find a lot of devices - they differ in characteristics and cost. As for materials, most often these products are made of carbon and stainless steels, cast iron, brass, bronze and even plastic.

Wafer Type Butterfly Valves

The design of this mechanism is a spring. Such solutions are considered to be the most compact among the products of modern industry. A disc equipped with a spring is used as a shutter. The overall dimensions of such devices can be from 15 to 20 mm. The principle of operation is simple. If pressure begins to fall in the pipeline, the spring will press the plate or the disc to the seat. The flow hole is overlapped. After restoring the pressure to the desired level, the spring will recede and the liquid will again be able to flow. In serious and large pipeline hydraulic systems , double-leaf structures equipped with shock absorbers are more often used. With these elements, a hydraulic shock is mitigated when the pump is stopped. The principle of operation is quite simple. The valve operates until the reinforcement is folded under the pressure of the flow. If the head goes in the opposite direction, then the plate will rise to its normal position. Such a valve has dimensions from 50 to 700 mm.

Advantages of the wafer element

Among the advantages of the reviews are compactness and low weight. The design does not have flanges, so they are much smaller than ball check valves. Also, the device has a lower weight. Other advantages include the possibility of installation not only horizontally, but also vertically. The installation of these systems is also not complicated, which is a big plus. The drawbacks include the need to dismantle the device for its repair.

Lifting Valve

In these systems, a special lifting slide is used as the gate mechanism - hence its name. If the medium pressure in the pipeline is not too high, then the element will sink into the saddle, thereby blocking the flow path back. When the pressure is high enough to operate the system, then the element will rise. These solutions are installed only on horizontal sections in the pipeline. It is very important that the spool axis is located strictly vertically. Ball valve in this regard is much easier. To him do not make such demands.

Ball Back Mechanism

This design differs from all others in that a ball is used as the closing element, which is pressed by the spring. Ball check valves for all its simplicity have a lot of advantages and are widely used not only in plumbing, but also at large pumping stations, as well as in various industries. As already noted, a ball is used as a locking element here. This is a special element made of cast iron or aluminum, which is covered with a layer of rubber. Thus, the ball valve effectively prevents the reverse movement of the medium. When the fluid moves in the desired direction, the element is pushed up the body - there is a special niche for it. If the direct movement of the flow stops, under the weight of its own weight, the ball will roll down into the lower part of the body and thereby block the movement of the medium. The ball return valve is also convenient because there is a special cover in the top part of the device with the possibility of removing it. It is designed to perform minor repairs and maintenance of the machine without the need for a complete removal of the device.

The cover is fixed to the body by means of bolts. And to reduce the risk of leakage, it is additionally equipped with a rubber sealing ring. In everyday life and in industry today, automatic solutions are also used. They are necessary in order to block the movement of the environment, if the operator for some reason can not do this. Here, a valve is used on a ball valve equipped with an automatic system. Reviews note the convenience of use. Electronics will automatically block the movement of the environment in the other direction and turn off the tap. This solution allows to secure the hydraulic systems.

Requirements for installation

The ball return valve must be properly installed - this is the only way it can properly perform its task. If the installation is horizontal, then the compartment with the ball should look up. Only in this case the element rolls down. If the installation is vertical, then the direction of flow should be from the bottom up.

Characteristics of ball valves

One of the main characteristics - the diameter of the hole or the nominal diameter. This parameter is denoted as DN. The feedback says that this parameter is conditional and does not always correspond to the real internal diameter of the pipeline. It is also necessary to take into account the thickness of the walls of the pipes. When choosing a valve, other factors should be taken into account. For example, a parameter such as the nominal pressure is important. This is the maximum value at which the ball valve flange can be safely operated. All valid numbers are specified in GOSTs - you can target the index 26349-84. Also, when selecting, European and American standards should be applied.

Variation of the connection

By type of installation check valves can be different. For example, for polypropylene pipelines, the element is only welded. There is also a ball flanged valve. What is this type of connection? Here fastening is carried out through flanges, but this is only relevant for large diameters. Alternatively, an alternative method of connection can be identified by means of a threaded coupling. Reviews say that this option can only be used on pipelines of small diameters. And, finally, the wafer type of the joint. Here the valve is installed between two elements in the pipeline.

Manufacturers and prices

Among products that are presented in stores for domestic pipelines, you can find both imported European products, and domestic. The price depends on the characteristics, namely the through diameter, as well as the working pressure and other parameters. For a pipeline with a diameter of 50 mm of the domestic manufacturer, the ball price will be 1,200 rubles per valve.