Comparing Gate Valves and Ball Valves
Figure 1: Ball valve (left) and gate valve (right)
Gate valves and ball valves are the most commonly used flow control valves in the market. They are generally used to control the flow of liquids and gasses. Although they are used in similar settings, there are a few important differences between these two valves. We discuss the differences between gate and ball valves and how to choose between them.
Table of contents
View our online selection of gate valves and ball valves!
Operation differences
A ball valve uses a rotary ball with a bore and a stem, as seen in Figure 2. When the handle attached to the stem is turned, it rotates the ball to open or close the valve. This valve is also called a quarter-turn valve because the handle only needs a 90° turn (quarter turn) to allow or block the flow of the media. The valve is open when the handle is parallel to the pipe, and it is closed when the handle is perpendicular to the pipe. For a more in-depth analysis of ball valves, view our ball valve technical article.
Figure 2: Ball valve stem (A) and rotary ball (B)
A gate valve uses a gate to control the flow of the media. A gate is a solid disk structure that is connected to the stem, as seen in Figure 3. The gate is lifted to open the valve and is returned down to its original position to close the valve. The valve is accompanied by a bonnet which, when rotated, controls the position of the gate. This valve is also called a multi-turn valve because it takes more than a 360° turn to fully open or close the valve. For a more in-depth analysis of gate valves, view our gate valve technical article.
Learn more in our article that covers the differences between lever handle and handwheel handle valves.
Figure 3: Gate valve stem (A) and gate (B)
Advantages and disadvantages
Due to the differences between gate and ball valve operation and design, each has certain advantages and disadvantages. Depending on the application, one is typically better than the other. View our table below for key differences between a gate and a ball valve.
Ball valve | Gate valve | |
Shut off mechanism | Fast shut-off with only a quarter turn (90° turn) to close the valve. | Slow shut off as it requires more than a 360° turn to shut off the valve. |
Water hammer | Fast opening and closing may cause water hammer.* | Slow opening and closing reduces the risk of water hammer.* |
Visual detection | The open or closed state of the valve can be visually detected with the position of the handle. | Difficult to detect the open or closed state of the valve. |
Cost | Typically more expensive than a gate valve of the same specifications. | Typically cheaper than a ball valve of the same specifications. |
Installation space | Requires more space than a gate valve to accommodate for quarter-turn handle. | Requires relatively less installation space than a ball valve. |
Size | Better suited for bore sizes below 2". | Better suited for bore sizes above 2". |
Leakage | Provides a tight seal even if used after a long period of time. | More prone to leaks than a ball valve. |
Durability | Durable and less prone to damage | The valve stem can be prone to corrosion, making the valve less durable. |
If the flow is abruptly stopped by rapidly shutting off the valve, pressure builds up due to the momentum of the moving medium, causing a short pressure surge. The pressure surge causes a noise that sounds like the pipes were struck by a hammer. A powerful water hammer can cause a rupture or leak in the system. To find out more about water hammer, read our water hammer technical article.
Selection criteria
The following criteria can be considered before selecting between a ball valve and a gate valve:
- Ports: A gate valve has 2 ports, while a ball valve can have more than 2 ports.
- Flow Capacity: A gate valve can provide a larger flow capacity than a ball valve as they are typically offered in larger diameters.
- Opening and closing speed: A ball valve is better suited for applications that require faster opening and closing speed or during emergencies due to its quarter turn on/off operation. A gate valve requires more than a 360° turn, making it slower than a ball valve to operate.
- Sealing: A ball valve provides a tight seal and has complete shut-off characteristics as compared to a gate valve. Therefore, ball valves are better suited for applications like natural gas where a proper seal long-term is important.
- Pressure: Both ball valves and gate valves are suitable for low-pressure applications. However, a gate valve is better suited for high-pressure applications. This is due to the fast opening/closing of the ball valve, which may cause a water hammer.
- Cost: A ball valve is generally more expensive than a gate valve of the same specifications. However, a ball valve is typically more durable and requires less maintenance compared to a gate valve, so it may be more economical in the long term.
- Connection: The choice of connection to the pipe is an important factor for both valves. To learn more about this subject, read our technical article on ball valve connection types.
Common applications
Both ball valves and gate valves are commonly used in residential and industrial applications.
- Gate valves are generally found in older plumbing systems and in applications where frequent shut-off is not required. Large water supply lines use gate valves due to their straight flow path and fewer flow restrictions. Ball valves are increasingly used in new plumbing systems with frequent shut-off requirements.
- Gate valves are used for application with slurries and viscous media because they are easier to clean and maintain. Ball valves are not desirable because they are difficult to clean, and the slurry particles may damage the rotary ball.
- Gate valves are used in power plants, mining, and water treatment applications, which are high-temperature and high-pressure environments.
- Ball valves are commonly used in fire protection systems and marine applications. They are best avoided in food, beverage, and pharmaceutical applications as they are difficult to clean and may cause contamination.
FAQ
Which is better: a gate valve or a ball valve?
It depends on the application. A ball valve is better suited for smaller flow rates, anything requiring more than 2 ports, or for durability/sealing concerns. A gate valve is typically cheaper, better for higher flow rates, and requires a smaller installation space.
What is the difference between a gate valve and a ball valve?
The main difference is in the operation. A gate valve moves a solid disk up and down to open/close the orifice. A ball valve rotates a ball (the orifice) with a bore in it 90 degrees to open/close the valve.
What is a ball valve used for?
A ball valve is used to control the flow and is typically used as a shut-off valve.
When would you use a gate valve?
A gate valve is ideal for applications with slurries, large flow rates, cost sensitivity, and for shut-off purposes.