Ball Valves vs Gate Valves: A Comparison of Features and Benefits
Gate valves and ball valves are two of the most widely used types of valves in industries and households. Both valve types are available in an extensive variety of temperature and pressure ratings, which make them suitable for a lot of applications.
Although all valves serve a similar purpose, however, the design of gate and ball valves differs, which makes them better for certain environments. Whether you are an industrialist or a house owner, you need to know the difference between a gate valve and a ball valve if you want to get the most benefit from your pipeline network. This blog will give you a detailed comparison between ball and gate valves so that you can make the right choice for your plumbing.
What is a Gate Valve?
This kind of valve uses a gate to block the flow of liquid in a pipeline. The gate is a barrier that can be raised or lowered to either completely stop or start the liquid flow in the pipeline. The main components of the gate valve are the valve body, disc, seat shaft, actuator and gland. Unlike other valve types, a gate valve has only two basic modes regarding liquid flow which are full flow and complete blockage. There is no third mode of slowing down liquid flow.
Gate Valve Design
The gate valve design is cylindrical with threaded ends on either side. The top end consists of a bonnet, which is a seal for other valve components. The stem houses a rod that is attached to the gate, and the gate is wedge-shaped like a disc. The user turns the valve handle to raise or lower the gate.
Benefits of Gate Valves
Gate valves have multiple benefits that make them immensely useful
When open, their gate valves offer no resistance at all for fluid flow due to their construction.
Liquid blocking is fail-proof and completely leakage-free when the valve is closed.
Gate valves are compatible with different types of liquids, from gas, liquids as well, and powdery materials. They are also utilized in high-viscosity fluid systems.
Another versatile feature of gate valves is that they are capable of bi-directional flow. This makes them suitable for plumbing systems where flow direction changes frequently within the system.
Drawbacks of Gate Valves
Although they offer a lot of benefits, gate valves have their fair share of drawbacks as well.
For pipeline systems that depend on controlling the speed of fluid flow, gate valves are useless since they are not designed to slow fluid flow. Even if the gate is partially opened, the gate material construction is not meant for partial closing, and the gate can get eroded very quickly.
Gate valves occupy more space than ball valves, and this is a negative since their large size makes them unsuitable for pipeline systems arranged in a congested space.
The gate component of the gate valve can get eroded by fluid flow over time, and this greatly affects the sealing capability of the valve.
The valve movement of the gate is slow, and multiple turns of the handles are needed to raise the gate or move it down to block the valve. In cases of emergency shutdowns or openings, the slow mechanism of the gate valve poses a risk, as the delay can cause damage to other components of the pipeline.
What is a Ball valve?
A ball valve is another type of valve commonly used in fluid systems. The main feature of the ball valve is a round component shaped like a ball, which acts as the flow barrier. A quarter-turn lever is used to rotate the ball and completely open or close the ball valve. The ball component has a hole, and when the hole is in the same direction as the fluid flow, the valve is open, and when the ball is rotated 90 degrees, the liquid flow becomes blocked, and the valve is shut. There are several types of ball valves suited for various pipeline systems.
Ball Valve Design
The functionality of the ball valve depends on three components: the ball, the seam and the seats they are all located inside a housing. The ball is fixed between two seats. The stem or lever is connected to the ball, making it easy to turn the lever to rotate the ball.
Benefits of Ball Valves
The opening and closing mechanism is swift, meaning that the ball valve is perfect for emergency shutoff.
An opened ball valve allows fluid to flow freely without posing any hindrance.
Ball valves offer foolproof sealing with no leaking risk.
Ball valves do not need a lot of maintenance as their design is quite simple.
Ball valves have a long usage life and can tolerate different pressures and environments. Unlike gate valves, the parts do not erode easily.
Ball valves are multi-purpose and can apart from blocking the flow it can also redirect the flow in the pipes.
Drawbacks of Ball Valves
Ball valves cannot handle thick liquids like slurry as the valve can get clogged, and the buildup can damage the valve over a long period.
High temperatures that exceed the temperature rating of the valve can cause immediate damage to the ball valve, so extreme temperature environments are off-limits for the ball valves.
Ball valves cannot be utilized in pipe systems with a pipe width of more than 2 inches, so the flow capacity of the ball valve is lower than that of the gate valve.
Making a Choice between a Ball valve and a Gate valve
When deciding between ball valves and gate valves, several crucial factors must be considered. Ball valves are typically recommended for low-pressure, low-temperature situations, especially in tight spaces, while gate valves are better suited for high-pressure, high-temperature environments where optimizing fluid flow is essential. Additionally, factors such as the speed of opening and closing, sealing capabilities, cost, and connection type should be taken into account.
For example, ball valves are preferred for applications requiring swift opening and closing or emergency shutoff, whereas gate valves require a full 360° turn, resulting in slower operation. Moreover, ball valves provide tight sealing and complete shutoff characteristics, making them ideal for applications like natural gas, where a reliable, long-term seal is crucial. Despite typically having a higher initial cost compared to gate valves with similar specifications, the durability and reduced maintenance requirements of ball valves often lead to long-term cost savings. When it comes to saving on maintenance costs, the ball valve quality is especially important, and buying a low-quality one would get damaged much more quickly. So, make sure to buy top-quality ball valves from a reputable vendor. This would save you a lot of headaches regarding replacement and maintenance expenses.
