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Home News Company News What are the differences between ball valves, globe valves, gate valves, and butterfly valves?

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What are the differences between ball valves, globe valves, gate valves, and butterfly valves?

What are the differences between ball valves, globe valves, gate valves, and butterfly valves?

Ball Valve  

The operation of a ball valve is simple: the stem rotates the ball 90 degreeswhen the bore aligns with the pipeline, it's open; when rotated another 90 degrees, it's closed. When you see a pipeline requiring fast action, tight shut-off, and frequent opening and closing, a ball valve is typically the first choice. Ball valves are commonly used in pipelines carrying natural gas, fuel gas, oil, compressed air, and many process media.

 

Another key feature: in a full-bore ball valve, the flow passage closely matches the pipes internal diameter once opened, allowing the medium to pass through almost straight, resulting in minimal local resistance. This makes them highly practical for transmission lines. On a single pipeline with dozens of valves, the pressure drop from each valve accumulates into the system resistance, which must be accounted for when sizing pumps and compressors. It's important to use ball valves correctly. While many people operate standard on/off ball valves fully open or fully closed, keeping them partially open for throttling over long periods causes high-speed media to erode the ball and seat continuously, eventually damaging the sealing surface. If a process requires regulation, specialized types such as V-port or modulating ball valves should be used instead.

 

Globe Valve  

A globe valve operates by moving the disc vertically to change the flow area between the disc and the seat. A slight turn of the handwheel lifts the disc slightly, increasing the flow area incrementally. This structure is well-suited for manual flow control, making globe valves common in steam, hot oil, and various process pipelines.

 

When frequent flow adjustment is required, globe valves are usually considered firstdue to their design. The gate-like structure allows the disc to move up and down, effectively controlling flow via stroke variation.

 

However, globe valves come at a cost. After entering the valve body, the medium changes direction, creating higher pressure loss compared to full-bore ball valves or fully open gate valves. For pipelines requiring high flow rates and low pressure drop, especially where valves remain fully open most of the time, globe valves are not the preferred choice.

 

Gate Valve  

A gate valve can be thought of as an "isolation valve." When the gate is raised, the pipeline opens; when lowered, it closes. Its ideal operating condition is clear: normally kept fully open, only closed during maintenance, equipment switching, or section isolation. Once fully lifted, the flow path remains smooth, minimizing impact on fluid flow. Therefore, gate valves are widely used in water supply and drainage, petrochemicals, utility systems, and main transmission lines.

 

Gate valves are generally designed for two positions: fully open or fully closed. Both ball and gate valves can achieve shut-off, but their applications differ. Frequent or rapid operations favor ball valves, while long-term full-open service with occasional isolation suits gate valves best.

 

Butterfly Valve  

For small pipe diameters, butterfly valves don't show significant advantages. But at DN300, DN500, or DN800, the benefits become apparent. As pipe size increases, valve selection can no longer focus solely on sealing and flow resistance. A simple butterfly disc mounted on a shaft offers compact structure, short installation length, and easy weight control. Thus, butterfly valves are widely used in circulating water, cooling water, HVAC, water supply and drainage, fire protection, and large-diameter water systems.

 

Butterfly valves have their own characteristics: even when fully open, the disc remains within the flow path. Therefore, local resistance still needs to be calculated in hydraulic design. For pump discharge lines or high-flow circulation pipes sensitive to pressure drop, the valves resistance coefficient must be included in system calculations.

 

Modern butterfly valves come in many designs. Standard mid-line soft-sealed models are common in water systems, while double-offset, triple-offset, and metal-sealed types are suited to different temperature, pressure, and sealing requirements.

 

Differences and Selection Criteria Among the Four Valves  

When faced with a new pipeline, follow this sequence:

 

First, determine the valves function: shut-off, isolation, throttling, or regulation. Clarify this point first.

 

Then, identify the medium. Clean water is easy to handle. But if the medium is steam, natural gas, corrosive fluids, slurries, or solid-laden particles, the choice of seat and sealing surfaces will immediately change.

Third, what are the design pressure and design temperature?  

It's important to note that we're referring to design pressure and design temperaturenot just the normal operating values shown on instruments.  

Valve pressure ratings cannot be considered independently of temperature and material. For example, a valve marked with PN or Class rating may have different pressure capacity under high-temperature conditions, which must be verified against the corresponding materials pressure-temperature rating.

 

Fourth, consider the size (nominal diameter), pressure drop, and actuation frequency.  

A DN50 valve and a DN1000 valve, even if both perform the same shut-off function, require different considerations. A valve operated twice a year versus one operated dozens of times per day will differ in terms of actuator type, sealing components, and maintenance requirements. Only after confirming these conditions should you proceed to select the body material, seat material, connection type, actuator, and accessories. This ensures a logically complete valve selection.

 

Selection should not be rigidly fixed. Although previous designs worked without issues, they can only serve as references. If the new system has different pressure, temperature, flow rate, or actuation frequency, the original selection must be re-evaluated. This is especially true for the same mediumpeople often develop a habit of using similar valves. Even though all involve water, requirements vary significantly between main circulating lines, pump discharge, heat exchanger branches, and flow control lines. Similarly, for steam, pipelines at 1.0 MPa and higher pressure levels require reevaluation regarding temperature, materials, sealing, and valve structure.

 

Therefore, during selection, follow this logical sequence: first determine the application, then identify the medium; next verify pressure, temperature, and nominal diameter; finally, specify materials, sealing, connections, and drive mechanisms.