How Much Pressure Can a Butterfly Valve Handle?

July 10, 2026
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How much pressure can a butterfly valve handle? There is no single answer. The actual pressure capability of a butterfly valve depends on its design type, pressure rating, body material, seat design, operating temperature, and specific application conditions.

In general:

Concentric Butterfly Valve: Commonly used for PN10–PN16 applications, with some heavy-duty designs available up to PN25.
Double Offset Butterfly Valve: Typically used for PN16–PN25 or Class 150–Class 300 pressure ratings.
Triple Offset Butterfly Valve: Mainly designed for high-pressure and high-temperature applications, commonly available in PN25–PN40 or Class 300–Class 600 ratings.

However, the pressure rating does not mean that a butterfly valve can continuously operate at the rated pressure under all conditions. The actual allowable working pressure can also be affected by operating temperature, material selection, seat design, applicable standards, and the characteristics of the medium.

What Is Butterfly Valve Pressure Rating?

Butterfly valve pressure rating refers to the maximum pressure that a butterfly valve is designed to withstand under specific operating conditions. Depending on the applicable international standards, pressure ratings are generally expressed using either PN rating (Pressure Nominal) or Class rating (Pressure Class).

What Is the Difference Between PN Rating and Class Rating?

Standard System	Common Ratings	Pressure Unit	Main Applications
PN (Pressure Nominal)	PN10, PN16, PN25, PN40	bar	Europe, Asia, and markets using EN/DIN standards
ASME Class (Pressure Class)	Class 150, Class 300, Class 600	PSI	North America and industrial projects following ASME/ANSI standards

The key differences between the two systems are:

PN Rating:
The number following PN represents the maximum allowable pressure (in bar) at the reference temperature of 20°C. For example, PN16 means the valve is rated for 16 bar at 20°C.
Class Rating:
The number following Class is not the actual pressure value. It is a pressure class designation, and the actual allowable pressure depends on the operating temperature and material. The pressure-temperature rating tables in standards such as ASME B16.34 should be consulted for accurate values.

For example, a typical Class 150 carbon steel valve can handle approximately 285 PSI (about 19.6 bar) at 38°C, rather than 150 PSI.

Typical Pressure Ranges by Butterfly Valve Type

Butterfly Valve Type	Typical Pressure Rating	Typical Applications
Concentric Butterfly Valve	PN10–PN16, with some heavy-duty designs up to PN25	Water supply, HVAC, fire protection systems
Double Offset Butterfly Valve	PN16–PN25 / Class 150–Class 300	Large diameter water systems, industrial water applications
Triple Offset Butterfly Valve	PN25–PN40 / Class 300–Class 600	High-temperature and high-pressure applications

Concentric double eccentric triple eccentric butterfly valve

Why Do Butterfly Valves Have Different Pressure Ratings?

Butterfly valves have different pressure ratings because different applications require different levels of pressure resistance, sealing performance, temperature capability, and service life.

1. Valve Design

Concentric Butterfly Valve:
Features a simple structure and relatively low manufacturing cost. It is commonly used for general water applications.
Double Offset Butterfly Valve:
The offset design reduces friction between the disc and seat during opening, helping to extend seat life and improve sealing performance.
Triple Offset Butterfly Valve:
Uses a metal seat design with a special offset structure to achieve low-friction sealing. It is suitable for higher-pressure and higher-temperature applications.

2. Body & Seat Materials

Body Materials:

Carbon steel and stainless steel valve bodies generally provide higher strength than cast iron materials.
Grey cast iron butterfly valves are commonly used for PN10–PN16 applications,
Ductile iron designs can reach PN10–PN25.
Carbon steel and stainless steel butterfly valves can cover some Class 150–Class 600 applications.

Seat Materials:

Metal seats generally provide better temperature and pressure resistance than soft seat materials such as EPDM and NBR.
Soft seats offer excellent elasticity and reliable sealing performance, but their temperature capability is usually limited (typically ≤120°C).
Metal seats can withstand temperatures above 600°C in some special designs and are suitable for high-temperature and high-pressure applications.

3. Valve Size & Medium

The larger the valve size, the higher the mechanical requirements for the valve structure.

Large diameter butterfly valves usually require:

Higher-strength valve shafts
More robust body designs
More reliable connection structures

The characteristics of the medium also need to be considered when selecting the appropriate pressure rating.

4. Operating Temperature

Pressure ratings are usually defined under standard temperature conditions.

As the operating temperature increases:

Material strength may decrease;
Sealing performance may change;
The allowable working pressure may be reduced.

Therefore, high-temperature applications require checking the corresponding pressure-temperature ratings rather than selecting a valve based only on the PN or Class rating.

How to Choose the Right Butterfly Valve Pressure Rating?

1. Confirm the Maximum System Operating Pressure

First, determine the highest pressure that may occur in the piping system, including:

Normal operating pressure
Pressure fluctuations during pump start-up and shutdown
Water hammer pressure
Other temporary pressure surges

The butterfly valve pressure rating should be higher than the maximum system operating pressure.

Selection recommendation:
The valve pressure rating should generally be at least 1.25–1.5 times higher than the maximum system operating pressure.

For example, if the maximum system pressure is 10 bar, a PN16 butterfly valve is recommended instead of PN10.

2. Consider Operating Temperature

Butterfly valve pressure ratings are usually defined under standard temperature conditions.

As the operating temperature increases:

The pressure resistance of the valve body material may decrease;
The performance of sealing materials may change;

Therefore, for high-temperature media, the applicable pressure-temperature rating should be checked instead of selecting a valve based only on the PN or Class rating.

3. Select Suitable Materials According to the Medium

Different media require different material configurations.

Clean water, fire water, and HVAC systems
→ Typically use a ductile iron body with an EPDM soft seat
Seawater systems
→ Chloride corrosion needs to be considered. Stainless steel or other higher corrosion-resistant materials are commonly selected.
Chemical media
→ The compatibility between sealing materials such as PTFE and the valve body material must be confirmed.

Butterfly-valve-pressure-selection

The actual performance of a butterfly valve depends on its design, materials, operating temperature, medium conditions, and application requirements. A properly selected butterfly valve can provide reliable sealing performance, longer service life, and stable operation under the required working conditions.

With extensive experience in butterfly valve manufacturing, Union Valve provides a wide range of concentric, double offset, and triple offset butterfly valves for water treatment, HVAC, fire protection, and industrial applications. We can offer suitable pressure ratings, material selections, and customized valve solutions based on specific project requirements.If you have any further questions, please feel free to contact us.