Ball Valve Types and Parts
Introduction of Ball Valve
Ball Valve Types and Parts:- The ball valve is a rotational motion valve. By rotating the hollow ball inside the valve, we can turn the valve on and off. It is very good at on/off operation, also good at throttling operation but the flow of fluid will cause abrasion to a ball that will cause leakage in close condition. When the hole of the ball is exactly at the pipe opening it is called open condition. When the hole is perpendicular to the valve opening then it is called close condition. You can observe different positions of the valve in the figure below. ( Types of Valves )
Different Parts of the Ball Valve
- The ball and seals are the most important parts of the valve. The ball is made up of the same metal as the valve body. The seal is made up of elastomeric material like rubber, TFE, Nylon, etc. Due to the use of rubber as seals material, we can’t use this valve at high temperatures.
- The stem is not the same as the gate valve and globe valve. Here, the stem is not fastened with a ball but the small rectangular element will fill in the groove of the ball.
- The bonnet keeps the ball in position and ensures ease of operation. The bonnet is fitted with the valve body and to ensure leakage-free operation packing is provided. Packing is of TFE or rubber.
Types of Ball Valve
1. Based on Body Type: ( Types of Ball Valve )
Here valve operation is the same in all types only difference is how parts are manufactured and assembled.
- Single Body
- Three-piece Body
- Split Body
- Top entry Body
- Welded Body
2. Based on Valve Port: ( Types of Ball Valve )
- Full Port: Here, the valve internal diameter is equal to the pipe diameter.
- Reduced port and venturi port: Here, valve internal diameter is one pipe smaller than pipe internal diameter.
Applications of Ball Valve
- As drains and vents for liquids and gaseous applications
- Found in flowing systems in ships and fire protection systems
- Not used in pharmaceutical industry due to difficulty in cleaning
- Used in clean services
Advantages of Ball Valve
- Open and close quickly and provides leak-proof operation
- Maintains and regulate high temperature, high flow and high pressure
- Low maintainance cost
- Low initial cost
- Long service life
Disadvantages of Ball Valve
- Very difficult to clean and prone to contamination
- Can’t use for permanent throttling