Gate and ball valves are the most commonly used flow control valves on the market. They are commonly used to control the flow of liquids and gases. Although they are used in similar settings, there are some important differences between these two valves. We discuss the differences between gate and ball valves and how to choose between them.
Ball valves use a rotating ball with a hole and stem. When the handle attached to the stem is turned, it rotates the ball to open or close the valve. The valve is also called a quarter-turn valve because the handle only needs to be rotated 90° (a quarter turn) to allow or stop the flow of media. The valve opens when the handle is parallel to the pipe and closes when the handle is perpendicular to the pipe.
Gate Valve
Gate valves use a gate to control the flow of media. The gate is a solid disc structure attached to the stem. The gate is lifted to open the valve and then returned to its original position to close the valve. The valve is equipped with a bonnet that controls the position of the gate when rotated. This valve is also known as a multi-turn valve because it requires more than 360° of rotation to fully open or close the valve.
* If the flow is suddenly stopped by closing the valve quickly, pressure is generated due to the momentum of the moving medium, which can cause brief pressure fluctuations. Pressure fluctuations can create a sound that sounds like a pipe being struck by a hammer. Powerful water hammer can cause a system to rupture or leak.
The following criteria can be considered before selecting ball and gate valves.
Ports: Gate valves have 2 ports, while ball valves can have more than 2 ports.
Flow: Gate valves can provide greater flow than ball valves, as they typically offer larger diameters.
Opening and Closing Speeds: Ball valves are better suited for applications that require faster opening and closing speeds or in emergency situations because of its quarter open/close operation. Gate valves require more than 360° of rotation and therefore operate slower than ball valves.
Sealing: Compared to gate valves, ball valves provide a tight seal and have full shutoff characteristics. Therefore, ball valves are better suited for applications such as natural gas where a proper seal is required over time.
Pressure: Both ball and gate valves are suitable for low pressure applications. However, for high pressure applications, gate valves are more suitable. This is due to the rapid opening/closing of ball valves which can lead to water hammer.
Cost: Ball valves are generally more expensive than a gate valve of the same size. However, ball valves are generally more durable and require less maintenance than gate valves. Therefore, ball valves may be more economical in the long run.
Connection: The choice of pipe connection is an important factor for both types of valves.
Ball Valve
Ball and gate valves are commonly used in residential and industrial applications.
Gate valves are typically used in older piping systems and in applications that do not require frequent shutoff. Gate valves are used in large water supply lines because they have straight flow paths and less flow restrictions. Ball valves are increasingly used in newer piping systems with frequent shutoff requirements.
Gate valves are used for slurries and viscous media because they are easier to clean and maintain. Ball valves are undesirable because they are difficult to clean and slurry particles can damage the rotating ball.
Gate valves are used in high temperature and high pressure environments in power plants, mining and water treatment applications.
Ball valves are typically used in fire protection systems and marine applications. They are best avoided in food, beverage and pharmaceutical applications where ball valves are difficult to clean and can cause contamination.
Check out our ball and gate valve selection online!
It depends on the application. Ball valves are better for smaller flow rates, any situation requiring more than 2 ports, or for durability/sealing issues. Gate valves are typically cheaper, better suited for higher flow rates, and require less installation space.
The main difference is operation. A gate valve moves a solid disc up and down to open/close the orifice. A ball valve rotates the ball (orifice) with the orifice 90 degrees to open/close the valve.
Ball valves are used to control flow and are often used as shut-off valves.
Gate valves are ideal for slurry, high flow, cost-sensitive and shut-off applications.
Check out our gate and ball valve selection online!
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