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How Globe Valves Work?

A globe valve is a multi-directional device that can open, close or throttle fluid flow. It consists of five major parts: the valve body, bonnet, handwheel, stem, and plug.

Valve Stem: The stem of a globe valve connects with the handwheel and operates the opening or closing action of the valve. It may be either smooth sliding or threaded.

Bonnet: The bonnet of a globe valve attaches to the stem and protects it from damage. Its seal, made from wear-resistant material, provides leak-proof closure for any media inside of the valve.

Ball Disc: The valve disc is another important element of a globe valve, used for low-temperature and low-pressure applications.

Seat Ring: The seat ring of a globe valve is where the disc fits and stops the fluid flow. Generally, this part can be screwed or threaded into an existing thread cut in the valve body to prevent removal during repairs or servicing.

Disc and Seat Capabilities: Globe valve discs come in various patterns, each providing its own advantages.

Globe valves are typically mounted, so the pressure is above the disk in high-temperature steam service and below it in lower-temperature or lower-pressure applications. This makes for easier operation and protects packing while reducing erosive action on seat and disk faces.

Generally, globe valves are designed for straight-through flow with ports oriented at right angles to the pipe axis. However, they come in various configurations, most often two-port but also three-port varieties.

Types of Globe Valves

Globe valves are widely used in industrial and marine applications to start, stop, and regulate flow, as well as isolate and throttle functions. 

Angle Globe Valve

Angle globe valves, also known as Y-pattern globe valves, are designed with an angled body that allows for a change in flow direction. 

This design is particularly useful in applications where space is limited or when a more convenient flow path is required. 

Angle globe valves find applications in various industries, including petrochemical, chemical, and oil and gas, where they are commonly used for throttling and control.

T-pattern Globe Valve

T-pattern globe valves, or straight-pattern globe valves, feature a straight-through flow path, making them suitable for applications where minimal pressure drop is crucial. 

These valves are often preferred in systems with high-velocity flows, such as steam applications. 

T-pattern globe valves are commonly utilized in power plants, steam distribution systems, and other industrial settings.

Bellows-sealed Globe Valve

Bellows-sealed globe valves incorporate a bellows element that provides an additional barrier between the process fluid and the environment. 

This design enhances the valve’s ability to prevent leakage, making it ideal for applications involving hazardous or toxic fluids. 

Bellows-sealed globe valves are frequently employed in chemical processing, pharmaceuticals, and other industries where leak-tight performance is critical.

Cryogenic Globe Valve

Cryogenic globe valves are specially designed to operate in extremely low-temperature environments, such as those found in liquefied natural gas (LNG) facilities and cryogenic storage systems. 

These valves are equipped with materials and features that ensure reliable performance under cryogenic conditions, providing effective control over the flow of cryogenic fluids.

Stop-check Globe Valve

Stop-check globe valves combine the functionalities of both a globe valve and a check valve. 

They allow for throttling or complete shutoff of fluid flow while also preventing backflow. 

These valves are commonly used in applications where the prevention of reverse flow is essential, such as in boiler feedwater systems and high-pressure steam lines.

Pressure-seal Globe Valve

Pressure-seal globe valves are designed to handle high-pressure applications, featuring a unique construction that enhances their ability to withstand elevated pressures. 

These valves are commonly used in power generation, oil and gas pipelines, and other systems where high pressures are encountered. 

The pressure-seal design ensures reliable performance and tight sealing under demanding conditions.

What’s the Application of Globe Valve

A globe valve is a type of valve that restricts or stops the fluid flow. They’re commonly found in piping systems transporting corrosives, viscous, or highly pressurized media.

They come in a range of patterns, each offering its own advantages. Furthermore, their ease of upkeep and ability to be repaired or replaced makes them an economical choice for many applications.

As its name implies, globe valves feature a spherical body. Two halves of this globe valve are separated by an internal baffle which contains an opening that acts as a seat for attaching a movable plug to close (or shut) the valve.

Globe valves are widely used industrial valves that can start, stop, and throttle fluid flow. They’re often found in systems requiring frequent throttling or regulating, such as vacuum systems, water hammer control, and systems operating at various temperatures.

Pros and Cons of Globe Valves

Pros of Globe Valves

Precise Flow Control: Globe valves excel at providing precise control over the flow of fluids. 

Their design allows for accurate throttling, making them suitable for applications that require fine adjustments to the flow rate.

Versatility: Globe valves are versatile and find application in a wide range of industries, including petrochemical, chemical processing, power generation, and water treatment. 

They are well-suited for various fluid types, temperatures, and pressures.

Good Shut-Off Capability: Globe valves offer excellent shut-off capability, ensuring a tight seal when closed. 

This makes them effective in preventing backflow and leakage, contributing to their reliability in critical systems.

Sturdy Construction: These valves are often built with robust materials, enhancing their durability and longevity. 

The materials used in their construction can be selected based on the specific requirements of the application.

Ideal for Throttling: The globe valve’s design, with a disc or plug that can be moved against the flow, makes it well-suited for throttling applications. 

This feature allows for precise control over the flow rate.

Cons of Globe Valves

Pressure Drop: Globe valves can cause a significant pressure drop across the valve, particularly in fully open positions. 

This can impact system efficiency, and in high-pressure systems, it may require additional energy to overcome the pressure drop.

Size and Weight: Globe valves can be relatively large and heavy compared to other types of valves. 

In applications where space and weight are critical considerations, the size and weight of globe valves may pose challenges.

Slower Operation: Compared to some other valve types, such as ball valves, globe valves generally have slower opening and closing times. 

This slower operation may be a limitation in systems requiring rapid response times.

Complex Design: The internal design of globe valves can be more complex than that of some other valves. 

This complexity may result in higher manufacturing costs and increased maintenance requirements.

Limited Use in High-Flow Applications: Globe valves are not always the best choice for high-flow applications, especially where minimal resistance and pressure drop are crucial. 

In such cases, other valve types like butterfly or ball valves might be more suitable.

How to Choose Between Globe Valve vs. Ball Valve

When selecting plumbing components, there are two primary valve types to consider: globe and ball. Both offer reliable on/off controls with distinct advantages that may be worth taking into account for your project.

When selecting a valve to control, start, or stop flow in a fluid system, it is essential to learn which type is most suitable for your application. The two most common types of fluid control valves are globe and ball valves.

Ball valves and globe valves differ in that they use a disk to open, while globe valves utilize a ball with an integral hole. When one opens the valve, fluid can pass through while the ball rotates to block its passage when closed.

The primary distinction between a ball valve and a globe valve lies in their closure elements. A ball valve features a spherical closure element that seals against an internal seat; on the other hand, globe valves feature disk-shaped closure elements that fit onto an outer seat.