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Home News Trunnion Ball Valve Vs Floating Ball Valve: J-VALVES Large Diameter Advantage
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Trunnion Mounted Ball Valves1

I.Introduction

Ball valves are widely used in industrial pipingsystems due to their reliable sealing performance and fast operation. Among them, trunnion ball valves and floating ball valves are the two most common structural types.

However, when it comes to large-diameter pipelines, high pressure systems, or demanding industrial applications, engineers often face an important question:

Which valve design provides better stability, sealing performance, and long-term reliability?

In this article, we explore the key differences between trunnion ball valves and floating ball valves, and explain why J-VALVES large diametertrunnion ball valves are often the preferred choice for heavy-duty industrial environments.


II.What is a Floating Ball Valve?

A floating ball valve features a ball that is not fixed by a lower shaft. The ball is held in place by two valve seats and can move slightly within the valve body.

When the valve is closed, line pressure pushes the ball against the downstream seat, creating a tight seal.

Key Characteristics

  • Simple internal structure

  • Lower manufacturing cost

  • Suitable for small to medium sizes

  • Ideal for low and medium pressure systems

Floating ball valves are widely used in industries such as:

  • Water treatment

  • Chemical processing

  • HVAC systems

  • General industrial pipelines

However, when the valve size increases, the operating torque and seat load also increase significantly.


III.What is a Trunnion Ball Valve?

A trunnion ball valve is designed with an additional mechanical anchoring structure. The ball is supported by upper and lower trunnions (shafts) that keep the ball fixed in position.

Instead of the ball moving under pressure, the valve seats move toward the ball to create the seal.

Key Characteristics

  • Fixed ball structure

  • Reduced operating torque

  • Better stability in high pressure environments

  • Excellent sealing performance for large diameter valves

Trunnion ball valves are commonly used in industries such as:

  • Oil & gas pipelines

  • Petrochemical plants

  • LNG facilities

  • Power generation

  • Long-distance transmission pipelines


IV.Structural Comparison

Feature

Floating Ball Valve

Trunnion Ball Valve

Ball Support

Floating, supported by seats

Supported by upper and lower trunnions

Suitable Size

Small to medium diameter

Medium to large diameter

Operating Torque

Higher in large sizes

Lower due to fixed ball design

Pressure Handling

Moderate pressure

High pressure capability

Sealing Mechanism

Ball pushed to seat

Seat pushed to ball

Stability

Limited for large pipelines

Excellent structural stability


V.Why Large Diameter Pipelines Prefer Trunnion Ball Valves

As pipeline diameter increases, the hydraulic force acting on the ball also increases significantly.

For floating ball valves, this can lead to:

  • Excessive seat wear

  • Increased operating torque

  • Reduced service life

Trunnion ball valves solve these challenges by fixing the ball and distributing pressure more evenly, which provides several advantages:

1. Reduced Operating Torque

The trunnion support structure significantly reduces friction and torque, making the valve easier to operate even in large diameters such as DN300, DN600, or larger.

2. Improved Sealing Reliability

The seat design allows for consistent sealing performance even under fluctuating pressures, which is essential for critical industrial systems.

3. Longer Service Life

Because the ball remains fixed, the wear between ball and seat is minimized, extending the valve's operational lifespan.

4. Better Performance in High Pressure Systems

Trunnion ball valves are widely used in high pressure and long-distance pipeline systems where reliability is essential.


VI.J-VALVES Large Diameter Trunnion Ball Valve Advantage

J-VALVES has extensive experience in manufacturing large diameter trunnion ball valves for global industrial markets.

Key advantages include:

1.Precision Engineering

J-VALVES valves are designed with high precision machining and strict quality control, ensuring excellent sealing performance and durability.

2.Wide Size Range

Available in multiple sizes including:

  • DN15 ~ DN1400

  • 1/2" ~ 56"

This makes them suitable for large industrial pipeline systems.

3.Multiple Material Options

To meet different working conditions, J-VALVES offers materials such as:

  • WCB carbon steel

  • Stainless steel (CF8 / CF8M)

  • Duplex stainless steel

  • Aluminum bronze

4.Compliance with International Standards

J-VALVES trunnion ball valves can be manufactured according to international standards including:

  • API

  • ANSI

  • DIN

  • ISO

This ensures compatibility with global pipeline systems and industrial projects.


VII.Typical Application Industries

J-VALVES large diameter trunnion ball valves are widely used in:

  • Oil and gas transportation pipelines

  • Petrochemical plants

  • LNG terminals

  • Power generation systems

  • Industrial fluid control systems

Their reliable performance makes them ideal for critical applications requiring high safety and long service life.


VIII.Conclusion

Both floating ball valves and trunnion ball valves play important roles in industrial piping systems. However, when dealing with large diameter pipelines, high pressure conditions, or demanding industrial environments, trunnion ball valves offer clear advantages.

With advanced manufacturing capabilities and extensive engineering experience, J-VALVES provides high-quality large diameter trunnion ball valves designed for reliability, durability, and optimal performance.

For industries seeking stable and efficient flow control solutions, J-VALVES remains a trusted choice.

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Nominal Size: 3/4 x 1/2 inch (DN20 x DN15), reduced bore Pressure Class: ASME Class 600 / PN100, 102.1 bar at 38°C Body Material: ASTM A182 F51 forged duplex, UNS S31803 PREN: Approximately 35 Ball: F51 with HVOF tungsten carbide or Stellite overlay Stem: F51, SS316 or 17-4PH, blowout proof Seat: RPTFE, Devlon, PEEK, or Stellite faced metal Bolting: B8M Class 2, alloy 718, or B7M for sour service End Connection: NPT, BSP, socket weld ASME B16.11, butt weld ASME B16.25 Bleed Port: Cavity bleed with plug or needle valve, lockable option Service Temperature: -29°C to +300°C, seat dependent Design Standard: API 6D, API 608, ASME B16.34 Test Standard: API 598, ISO 5208, cavity test through bleed port Sour Service: NACE MR0175 available