If you are looking for information on the Difference between Gate Valves and Globe Valves, you’ve come to the right place. Both types of valves perform the same function – controlling flow – but they have very different designs. If you’re looking for a valve to regulate a large flow of liquid, you might want to choose the former.
A common difference between a globe valve and a gate valve is the configuration. The former has a single, fixed valve stem and is typically used for larger applications where regular maintenance is required.
A globe valve, on the other hand, is typically designed for frequent maintenance because the disc and seat can be replaced fairly easily. The main difference between a gate valve and a globe valve is the design. A gate valve has an on/off feature. A globe valve is intended to regulate flow and is used when there is a need to isolate the media.
If you want to know more about the difference between a gate valve and a globe valve, continue reading this article.
What is a Gate Valve?
Gate valves are used to control flow in narrow spaces, and they are often more efficient than a plug-type valve in high-pressure service. Their slow-responding design makes them an excellent choice for applications where there’s limited space or where pressure changes often cause damage to the stem.
A gate valve is a better choice in high-pressure service than a plug-type valve because it is much cheaper. Despite this, gate valves are not suited for high-temperature service, and they are not suitable for marine atmospheres.
A gate valve consists of seven main parts, including a bonnet, a handwheel, a stem, a gasket, and a gate. The parts of a gate valve may have varying designs depending on the application. But their main function remains the same: controlling flow.
What is Globe Valve?
If you’re looking for a valve that allows fluids to flow between two positions, a globe valve is an ideal choice. These valves come in two main types: bellow sealing and packing sealing. Each type of valve has certain benefits and drawbacks.
Generally, the most common feature of a globe valve is its large opening for the valve disc assembly. The globe design allows the valve to cantilever the disk onto the valve stem, making it heavier than other valves of the same size and flow capacity. The advantage of a globe valve is its simplicity. Globe valves require less maintenance and can be operated manually.
Another type of globe valve has a stem that moves up to control flow. A disc containing a ball, composition, or plug sits on the stem. The stem is usually screwed into the body of the valve, with a seat in the opposite direction. A seat is installed on the valve in a plane parallel to the flow, which helps with a quick shutoff.
Difference between Gate Valve and Globe Valve
When choosing a valve, you should consider how complex the construction is. Gate valves, on the other hand, have a simple design with many internal components located on top of the valve body. Gate valves may have a rising stem or a non-rising stem. The main difference between these two valves is the way they control fluid flow. While both types of valves can control flow, the main difference between them is the overall pressure drop and the amount of resistance they offer.
Regardless of their structural differences, gate valves are an excellent choice for tight sealing applications. Gate valves use a patented curved body with a perpendicular movement. They also consume less power than globe valves. Their energy efficiency lowers the total cost of ownership. Because they are relatively simple, gate valves are easy to operate compared to other designs. They are also less complicated than globe valves, which makes them an excellent choice for applications where high pressure is not a primary concern.
The key difference between a gate valve and a globe valve is the way that it closes and opens. A gate valve closes when fully opened, while a globe valve remains open for a limited period. While a gate valve is easy to identify when fully open, it’s hard to close. Flow resistance in the valve body path is almost zero. Hence, a gate valve requires less labor and time to operate.
While both globe valves and gate valves are useful for on-off and shutoff control in the oil and gas industry, they have different functions. A globe valve, for instance, is used to control flow within a pipe, while a gate valve can change flow direction and rate without a change in pressure. Therefore, a gate valve is generally a better choice for on-off control in applications where flow is not a primary concern.
Pros and Cons of a Gate Valve
Pros
Low Fluid Resistance: One of the key advantages of gate valves is their low fluid resistance when fully open.
The unobstructed passage allows for efficient flow with minimal pressure drop, making gate valves suitable for applications where low fluid resistance is crucial.
Tight Sealing: Gate valves provide excellent sealing capabilities when fully closed.
The design features a gate that comes into full contact with the valve seat, preventing any leakage.
This tight sealing is beneficial in applications where preventing the flow of fluids is critical.
Full Bore Design: Gate valves typically have a full bore design, meaning the internal diameter of the valve matches the pipe’s diameter.
This ensures unrestricted flow when the valve is open, minimizing turbulence and pressure loss in the system.
Suitable for Slurries: Gate valves can handle fluids with suspended particles, making them suitable for applications involving slurries.
The straightforward design of the gate allows for easy passage of particles when the valve is open, and the tight seal prevents particle leakage when closed.
On/Off Service: Gate valves are well-suited for on/off service, where the valve is either fully open or fully closed.
Their simple operation and reliable sealing make them effective for applications where frequent cycling between open and closed positions is required.
Cons
Slow Operation: Gate valves are not ideal for applications that require rapid valve operation. The movement of the gate, especially in larger valves, can be relatively slow.
In situations where quick response times are critical, other types of valves, such as ball valves, may be more suitable.
Not Ideal for Throttling: While gate valves excel in on/off service, they are not well-suited for throttling or regulating flow.
Attempting to partially open or close a gate valve can lead to increased wear and may cause damage to the seating surfaces over time.
Potential for Jamming: Gate valves may be susceptible to jamming in applications where the system contains solid particles or debris.
The accumulation of foreign material between the gate and seat can impede smooth operation and, in some cases, lead to valve failure.
Limited Control Options: Compared to some other valve types, gate valves offer limited control options.
They lack the fine-tuned control features found in valves designed specifically for throttling applications.
If precise control of flow rate is a primary requirement, alternative valve types may be more suitable.
Size and Weight: Gate valves, especially in larger sizes, can be heavy and bulky.
This can pose challenges in installations with space constraints or when the valve needs to be manually operated.
The weight of the gate and stem may require additional support structures.
Pros and Cons of a Globe Valve
Pros
Precise Flow Control: Globe valves provide excellent control over the flow rate, making them suitable for applications requiring precise regulation.
Versatility: These valves are versatile and can handle a wide range of pressures and temperatures.
Throttling Capability: Globe valves are well-suited for throttling services, allowing fine adjustments in the flow.
Less Noise: Compared to some other valve types, globe valves typically produce less noise during operation.
Cons
Pressure Drop: Globe valves often cause a significant pressure drop across the valve, impacting system efficiency.
Complex Design: The internal components of globe valves are intricate, requiring careful maintenance and occasional repairs.
Limited Shut-Off Capability: While they offer good throttling, globe valves may not provide a tight shut-off, which can lead to minor leakages.
Size and Weight: In larger sizes, globe valves can be bulky and heavy, affecting the overall system design.
Key Takeaway: How Can You Tell a Gate Valve From a Globe Valve?
The key difference between a gate valve and a globe valve is the way that it closes and opens.
A gate valve closes when fully opened, while a globe valve remains open for a limited period.
While a gate valve is easy to identify when fully open, it’s hard to close. Flow resistance in the valve body path is almost zero.
Hence, a gate valve requires less labor and time to operate.
While both globe valves and gate valves are useful for on-off and shutoff control in the oil and gas industry, they have different functions.
A globe valve, for instance, is used to control flow within a pipe, while a gate valve can change flow direction and rate without a change in pressure.
Therefore, a gate valve is generally a better choice for on-off control in applications where flow is not a primary concern.
