Which is better gate valve or ball valve?


Gate valves 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.

1.Selection criteria

The following criteria can be considered before choosing between a ball valve and a gate valve.

Ports: Gate valves have 2 ports, while ball valves can have more than 2 ports.

Flow rate: Gate valves can provide a greater flow rate than ball valves as they are usually available in larger diameters.

Opening and closing speeds: Ball valves are more suitable for applications requiring faster opening and closing speeds or in emergency situations because of their 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 a complete shut-off characteristic. Therefore, ball valves are more suitable for applications such as natural gas where a proper seal is required over a long period of 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: A ball valve is 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, in the long run, ball valves may be more economical.

Connection: The choice of pipe connection is an important factor for both types of valve. To learn more about this important topic, read our technical article on ball valve connection types.

2.Operating differences

Ball valves use a rotating ball with a bore 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 known as a quarter turn valve because the handle only needs to be rotated by 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 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 fitted with a bonnet which controls the position of the gate when rotated. This type of valve is also known as a multi-turn valve as it requires more than 360° of rotation to fully open or close the valve. For a more in-depth analysis of Gate valves, please contact us.


3.Comparison of advantages and disadvantages

Due to the differences in operation and design between gate and ball valves, they each have advantages and disadvantages. Depending on your application, one is usually better than the other. Check out the table below for the main differences between gate and ball valves.

 

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

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.

4.Common applications

Ball and gate valves are commonly used in residential and industrial applications.

Gate valves are typically used in older piping systems and in applications where frequent shut-off is not required. Gate valves are used in large water supply lines because they have a straight flow path and less flow restrictions. Ball valves are increasingly used in new pipeline systems with frequent shut-off requirements.

Gate valves are used for slurries and viscous media as 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-fighting systems and marine applications. They are best avoided in food, beverage and pharmaceutical applications as ball valves are difficult to clean and can lead to contamination.

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