Whether you’re designing an industrial-scale piping system or making repairs to residential plumbing, understanding the types of valves your system requires is crucial. In this post, we’ll explore the most common types of valves — globe, gate, and ball — and discuss their typical applications.
Globe valves are control valves designed to stop, start, and regulate the flow of media through a pipe. Externally, they feature a spherical body design. Internally, a plug-like disc is attached to the end of a threaded, rotating stem, which raises and lowers to control media flow. As part of the linear motion valve family, the valve mechanism moves in a straight line.
Globe valves offer a tight seal with minimal leakage risk, making them a popular choice for high-pressure, industrial piping systems.
Globe valves are designed so that the media flowing through them does not travel in a straight line. Instead of encountering a perpendicular blockage, the media takes a slight vertical detour up through the valve cavity, where it meets the plug disc. As the valve stem is turned via a wheel and raises to allow media through, the disc moves parallel to the flow. The stem's position indicates whether the valve is open or closed.
This vertical movement enables the globe valve to regulate media flow, rather than simply stopping or starting it. The distance between the disc and the seat determines the flow rate: the farther apart the disc and seat are, the higher the volume of media passing through. Globe valves are ideal for throttling, or regulating the flow of media while in a partially open position. This makes starting and stopping flow less abrupt, helping to prevent water hammer.
Due to their design, which forces media to change direction from horizontal to vertical, globe valves create a high-pressure drop. They are best used in applications requiring unidirectional flow, where significant pressure changes are not an issue and where safety and leakage prevention are primary concerns. Globe valves are commonly found in piping systems that transport corrosive, viscous, highly pressurized, or extremely hot or cold media.
Most of the working parts of a globe valve lie inside the cavity, and access to the internal components is through the top; this is known as a top-entry design.
Gate valves are linear motion valves used solely to start or stop the flow of media through a pipe. They are considered shutoff valves rather than control valves, as they are not ideal for throttling.
Gate valves feature a flat or wedge-shaped disc on the end of a threaded stem, which is turned via a wheel to raise and lower the disc, thus operating the valve. These valves provide a tight shutoff, making them commonly used for isolating media. Unlike globe valves, gate valves do not force media to change direction, resulting in minimal pressure drop.
Gate and globe valves often work in tandem within a piping system and are the two most common types of valves. Gate valves can be designed with either rising or non-rising stems, which is beneficial when space optimization is critical.
Gate valves operate by turning the stem clockwise or counterclockwise to raise or lower the disc inside the pipe. When closed, the disc lodges between seats at the base of the valve, forming a complete barrier perpendicular to the media flow. The disc can be wedge-shaped, knife-shaped, or parallel-panel-shaped.
Most of the internal components of a gate valve are located in the top part of the valve body, facilitating maintenance access.
Gate valves create lower pressure drops than globe valves because they do not divert the media flow. Once open, the flow path matches the valve cavity size, offering minimal resistance to flow. Gate valves are ideal for applications where low-pressure drops are critical, and their bidirectional nature makes them more versatile than unidirectional valves.
A drawback of gate valves is the potential for disc misalignment with the seat due to strong vibrations from the media. Therefore, it is crucial to keep gate valves fully open or fully closed to prevent damage caused by vibrations, which can shorten valve lifespan. Additionally, the abrupt shutoff of gate valves can induce water hammer, leading to significant damage in industrial environments.
Gate valves excel in applications requiring tight sealing or media isolation. They are unsuitable for regulating flow in partially open positions and are commonly used in industrial oil and gas pipelines, irrigation systems, and marine industries. For instance, gate valves with non-rising stems are preferred on ships due to their compact vertical profile.
Globe valves generally have more robust construction and reliable sealing so are ideal for harsh operating conditions. In gate valves, the stem is usually exposed to the flow media, which causes leakage in the long run due to deterioration. But globe valves can shut off flow without any contact with its stem.
Unlike gate or globe valves, ball valves are quarter-turn valves that utilize a spherical ball with a hole in the middle (known as a bore or port) to control the flow of media. The port allows media to pass through the valve body when open, and the ball is rotated 90 degrees to stop flow, aligning the port perpendicular to the valve body in the closed position.
Ball valves are multidirectional quarter-turn valves where the rotating ball regulates media flow through the port. The stem, which controls ball rotation, is connected to a perpendicular lever or actuator. When the lever is parallel to the pipe, the valve is open; when perpendicular, the valve is closed.
Ball valves can also be operated by actuators—attachments that open or close the valve. These actuators can be hydraulic, electric, or pneumatic.
One characteristic of ball valves is their exponential flow characteristic, meaning the flow rate changes exponentially when the valve is opened or closed. This makes precise flow rate control challenging, so ball valves are typically not ideal for throttling applications.
Ball valves are favored for their compact design, fast operation, and long service life, making them suitable for applications requiring reliable on/off control. Industries such as oil, gas, automotive, chemical processing, and manufacturing commonly use ball valves. Due to their minimal motion—unlike the multi-turn stems of globe or gate valves—ball valves endure longer and are less prone to corrosion or damage. For applications needing prolonged valve closure, ball valves provide secure sealing.
Pros | Cons | |
Glove Valves | · Can regulate media flow · Can handle high-pressure, high-temperature, corrosive or viscous media · Low chance of leakage | · Create a high-pressure drop · Introduce resistance to media flow |
Gate Valves | · Economical option for on/off control · Multidirectional · Offer little resistance to media flow | · Not ideal for regulating media flow: Cannot handle the sustained flow of media in a partially open position · Can cause water hammer · Prone to leaks: less durable than ball valves |
Ball Valves | · Long lasting and durable · Versatile media compatibility · Compact · Provide fast cycle speeds · Good for high-pressure, high-volume applications · Offer little resistance to media flow | · Not ideal for regulating flow · Fast cycle time can lead to water hammer |
Now that you understand the differences between globe, gate, and ball valves, you can select the ideal valve for your specific application. Kairuite Valve is your go-to expert for all things ball valves—we can guide you in the right direction, no matter your valve needs. Contact us today to ask questions or request a quote.
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