Are ball valves cheaper than gate valves?
Jul. 29, 2024
Gate Valve vs Ball Valve - How They Work | Tameson.com
Gate Valve vs Ball Valve - How They Work
Figure 1: Ball valve (left) and gate valve (right)
If you are looking for more details, kindly visit Yulin Machinery.
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 liquid and gases. 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.
View our online selection of gate valves and ball valves!
-
Ball Valves
-
Gate 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.
Figure 3: Gate valve stem (A) and gate (B)
Advantages and Disadvantages
Due to the differences between gate and ball valves operation and design, there are certain advantages and disadvantages to each. Depending on your application, one is typically better than the other. View our table below for key differences between a gate and 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
Open or closed state of valve can be visually detected with position of the handle.
Difficult to detect the open or closed state of 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
Want more information on wellhead ball screw (bso) gate valve wholesale? Feel free to contact us.
Related links:How It Works: Check Valves
Top 10 Ball Valve Manufacturers in China
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 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
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 and this causes a short pressure surge. The pressure surge causes a noise which 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 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 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, for high pressure applications a gate valve is better suited. This is due to the fast opening/closing of the ball valve that 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, a ball valve may be more economical long-term.
- Connection: The choice of connection to the pipe is an important factor for both valves. To learn more about this important subject, read our Ball Valve Connection Types technical article.
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 less 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 not used in food, beverage and pharmaceutical applications as ball valves are difficult to clean and may cause contamination.
FAQ
Which is better gate valve or 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 gate valve and 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 that have slurries, large flow rates, cost sensitive, and for shut off purposes.
View our online selection of gate valves and ball valves!
-
Ball Valves
-
Gate Valves
Gate Valves vs. Ball Valves: How to Choose the Right One
As we mentioned, ball valves operate by rotating a ball 90° while gate valves are controlled by moving a gate up or down. Because of their design, ball valves can perform an almost immediate shutoff, whereas gate valves are not able to act as quickly. This makes ball valves a better choice for applications where fast cycle speed is desired.
The 90° operation of ball valves makes them faster to cycle, both manually and with an actuator. This is a benefit in most instances but can potentially cause water hammer in high-pressure applications. If the pressure is high enough, the pipe could weaken or even break, which is why users of manual ball valves should turn the levers slowly to avoid water hammer.
Applications & Use Cases
Gate Valve Uses Ball Valve Uses Shutoff and isolation service for:- Wastewater Plants
- Power Plants
- Mining
- Process Plants
- Large Water Supply Lines
Gate valves are commonly found in older home plumbing systems.
On/off control for specialized industries including:- Oil & Gas
- Food & Beverage Equipment
- Automotive
- Vehicle Wash Systems
- Power Processing
- Pharmaceutical
- Chemical Admixtures & Treatment
- Irrigation & Water Treatment Equipment
- Manufacturing Facilities
Ball valves are also found in newer home plumbing systems.
Cost
In the gate valve vs. ball valve debate, cost is a major differentiating factor. Up front, gate valves are less expensive than ball valves, but they can be more susceptible to corrosion which means they will need repairs and replacement more frequently. Ball valves have a higher initial cost, but they are the better choice for longevity since they are more durable and highly effective at forming tight seals.
Maintenance
As we just discussed, gate valves are, in general, less durable than ball valves. In moderate or high cycle applications, gate valves will require routine maintenance or replacement. Most ball valves are designed to be maintenance-free and should be replaced rather than repaired. Three-piece ball valves, however, are designed so that the valve seats and seals can be easily replaced without removing the valve from service. This is why 3-piece ball valves are often used in high cycle or high pressure applications where valve seal failure is likely to occur more quickly. However, 3-piece ball valves typically come with a higher up-front cost than the more popular 1-piece or 2-piece body constructions.
For more information, please visit api 6a ball screw gate valves.
60
0
0
Comments
All Comments (0)