Many industries use ball valves, and they are one of the most widely used valve types. There is still a growing demand for ball valves. Do you ever wonder how ball valves make an impact on your applications? This article will show you how ball valves work and what their components do. Additionally, we will show you how a ball valve works to help you better understand it before you use it.
What is a Ball Valve?
An integral ball-like disc acts as a barrier when the ball valve is closed, as its name suggests. It is commonly designed as a quarter-turn valve by ball valve manufacturers, but it can also be a rotatory valve when controlling media flow or diverting it.
What Are Ball Valves Used For
It is often necessary to use ball valves in applications where tight seals are required. There is a low-pressure drop associated with them. Its 90-degree turn makes it easy to operate even when the media is high in volume, pressure, or temperature. The long service life of these products makes them quite economical.
It is ideal to use ball valves for gases or liquids containing few particles. It is difficult to use these valves with slurries since the latter easily damage the soft elastomeric seats. Ball valves have throttling capacities, but they are not used as such because friction from the throttling can damage the seats as well.
Parts of a Ball Valve
It is possible to classify valves in a variety of ways. Seven valve components are common to all valves, whatever the case may be.
Body
An entire ball valve is supported by its body. By acting as a barrier to the pressure load from the media, it prevents pressure from transferring to the pipes. All components are held together by it. There are three types of joints connecting the body to the piping: threaded bolted, and welded. It is possible to categorize ball valves by the type of body, which is usually cast or forged.
Stem
The stem is responsible for opening and closing the valve. Also, this is the mechanism that connects the lever, handles, or actuator to the ball disc. It is the stem that rotates the ball disc to open or close it.
Packing
This gasket seals the bonnet and the stem. It is important to install properly in this area since many problems occur here. When the fittings are too loose, leaks occur. Stem movement is restricted when the stem is too tight.
Bonnet
An opening in a valve is covered by a bonnet. As a secondary barrier, it prevents pressure from entering. After all the internal components are inserted inside the valve body, the bonnet holds them together. The bonnet is usually forged or cast from the same material as the valve body.
Ball
The disc of the ball valve can be seen here. When the disc is closed, the media pressure acts against it as the third most important pressure boundary. Steel or other durable materials are commonly used to manufacture ball discs. A ball disc can either be suspended, as in the case of the floating ball valve or mounted, as in the case of the trunnion-mounted ball valve.
Seat
The ball disc rests on this ring, sometimes called the seal ring. A ball disc’s seat may be attached to the ball or not, depending on its design.
Actuator
Ball valve actuators create the rotation needed to open the disc by rotating the ball valve. There is often a power source attached to these. It is possible to control some actuators remotely so valves can still work in remote or difficult-to-reach areas.
Handwheels can be used to operate ball valves manually. As well as solenoid actuators, pneumatic actuators, hydraulic actuators, and gear actuators, there are also gear actuators.
How Does a Ball Valve Work?
In general, ball valves work in this way. A quarter turn of the lever or handle is required to open the valve, whether operated manually or by an actuator. The force is transferred to the stem, which opens the disc.
Ball discs rotate with their hollowed sides facing the flow of media. A perpendicular lever and parallel port are in a position in about the flow of media at this point. To prevent the handle from turning more than a quarter-turn, there is a handle stop near the connection between the stem and bonnet.
By moving the lever back a quarter turn, the valve can be closed. As the stem turns, the ball disc is blocked from flowing in the opposite direction. In this position, the lever is parallel to the port, and the port is perpendicular to the lever.
You should, however, be aware that ball disc movement can be divided into three types. The working operations of each of these are different.
How Does a Three-Way Ball Valve Work
Ball valves are available in many variants, such as 3-way ball valves and ball valves made of different materials. The 3-way ball valve working mechanism is also different from the common ball valve.
How Does A Floating Ball Valve Work
There is a balling disc suspended on the stem of the floating ball valve. Due to the lack of support at the bottom of the ball disc, ball valves are known for their tight seals.
Upstream linear pressure from the media pushes the ball towards the downstream cupped seat as the valve closes. This adds to the sealing factor of the valve by providing positive valve tightness. When the valve is closed, the downstream seat of the floating ball valve carries the internal pressure.
How Does A Trunnion Ball Valve Work
Trunnion-mounted ball valves are another kind of ball disc design. At the bottom of the ball disc, there are trunnions, which keep the ball disc stationary. Additionally, these trunnions absorb the force from the pressure load when the valve closes, reducing friction between the ball disc and the seat. Both upstream and downstream ports are sealed with pressure.
As the valve closes, spring-loaded seats move against the ball, which rotates only on its axis. Seats are pushed tightly against balls by these springs. The trunnion-mounted ball type is suitable for applications that don’t require high pressure to move the ball to the downstream seat.
Last but not least, rising stem ball valves function using tilt-and-turn mechanisms. When the valve closes, the ball disc wedges against the seat. Opened, the disc tilts away from the seat to allow media to pass through.
Aira Euro Automation is the leading flanged ball valve manufacturer in India. We offer various types of industrial valves like ball valves, butterfly valves, control valves, and many more.
Also, read “Pneumatic Actuated Ball Valve knowledge“
