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Home News Welded Trunnion Mounted Ball Valve: High Pressure Pipeline Solution for Oil And Gas Applications
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Introduction

In high-pressure pipeline systems, valve reliability directly affects the safety and efficiency of the entire process. Industries such as oil & gas transportation, natural gas transmission, LNG, and petrochemical processing require valves that can withstand high pressure, temperature variations, and long-term continuous operation.

The Welded Trunnion Mounted Ball Valve is designed to provide excellent mechanical strength, reliable sealing performance, and reduced maintenance requirements. The valve shown in the image features a 3-piece welded end structure, LF2 low-temperature carbon steel material, and trunnion mounted ball design, making it suitable for demanding pipeline applications.

J-VALVES specializes in manufacturing high-performance welded trunnion mounted ball valves according to international standards, providing reliable solutions for critical energy and industrial projects.

What Is a Welded Trunnion Mounted Ball Valve?

A Welded Trunnion Mounted Ball Valve is a fixed ball valve with welded pipe ends instead of traditional flanged connections. The ball is supported by upper and lower trunnions, allowing it to remain stable under high-pressure conditions.

Unlike floating ball valves, the trunnion design transfers the pressure load from the ball to the trunnion support system, reducing seat stress and operating torque.

Main components include:

  • Fixed trunnion-supported ball

  • Welded valve body

  • Stem and anti-blowout structure

  • Double sealing seats

  • Fire-safe sealing system

  • Actuator mounting platform

This design makes it an ideal choice for large diameter and high-pressure pipeline systems.

Key Advantages of Welded Trunnion Mounted Ball Valves

1. Superior Strength for High Pressure Applications

The welded body structure provides excellent mechanical integrity compared with traditional bolted valve designs.

Advantages include:

  • Reduced potential leakage points

  • Improved structural strength

  • Better resistance to pipeline stress

  • Suitable for high-pressure environments

The LF2 material shown in the image is commonly used for low-temperature and high-pressure applications due to its excellent toughness and reliability.

2. Reliable Sealing Performance

The trunnion mounted design provides stable sealing performance even under high-pressure operation.

The pressure-assisted seat structure helps maintain tight sealing by pushing the seat toward the ball when pipeline pressure increases.

Benefits include:

  • Low leakage performance

  • Stable shut-off capability

  • Long sealing service life

  • Reliable operation under pressure fluctuations

For critical pipeline isolation, welded trunnion ball valves provide enhanced safety and operational reliability.

3. Low Operating Torque

Because the ball is supported by trunnions, the valve requires less torque compared with floating ball valve designs.

This provides:

  • Smaller actuator requirements

  • Easier operation for large sizes

  • Reduced operating energy consumption

  • Improved automation efficiency

The low torque feature makes welded trunnion mounted ball valves widely used in long-distance pipeline systems.

Welded End Design Advantages

The welded connection design eliminates the need for additional flange connections, providing several benefits.

1. Reduced Leakage Risk

Compared with flanged connections, welded ends reduce external leakage points and improve system integrity.

2. Space Saving Installation

The compact welded structure is suitable for:

  • Underground pipelines

  • Long-distance transmission lines

  • Limited installation areas

3. Long-Term Reliability

A welded connection provides excellent resistance against vibration, temperature cycling, and external mechanical stress.

Applications of Welded Trunnion Mounted Ball Valves

Oil and Gas Transmission Pipelines

These valves are widely used in:

  • Natural gas pipelines

  • Crude oil transportation systems

  • Compressor stations

  • Pipeline isolation points

Their high-pressure capability and reliable sealing performance ensure safe fluid control.

LNG and Low Temperature Systems

With suitable low-temperature materials such as LF2 carbon steel, welded trunnion mounted ball valves can be applied in:

  • LNG transportation systems

  • Cryogenic process pipelines

  • Gas processing facilities

The material provides excellent impact toughness and stable performance under low-temperature conditions.

Petrochemical Industry

Petrochemical systems often require valves that can handle high pressure and continuous operation.

Typical applications include:

  • Process pipelines

  • Storage systems

  • Refinery units

J-VALVES Advantages in Welded Trunnion Mounted Ball Valve Manufacturing

As a professional industrial valve manufacturer, J-VALVES provides customized welded trunnion mounted ball valve solutions for global energy and industrial markets.

1. Professional High Pressure Valve Manufacturing

J-VALVES has extensive experience in producing:

  • Trunnion mounted ball valves

  • Welded end ball valves

  • High pressure pipeline valves

  • Low-temperature service valves

2. Advanced Material Selection

According to application requirements, J-VALVES provides various material options, including:

  • LF2 low-temperature carbon steel

  • WCB carbon steel

  • Stainless steel

  • Duplex stainless steel

  • Special alloys

Material selection is optimized according to pressure, temperature, and operating media.

3. Strict Quality Control

Each welded trunnion mounted ball valve undergoes comprehensive inspection, including:

  • Material verification

  • Pressure testing

  • Seat leakage testing

  • Dimensional inspection

  • Functional operation testing

These procedures ensure reliable performance before delivery.

4. International Standard Compliance

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

  • API 6D

  • ASME B16.34

  • ISO 17292

  • NACE MR0175 (when required)

Conclusion

The Welded Trunnion Mounted Ball Valve is a reliable solution for high-pressure and long-distance pipeline applications. With its fixed ball structure, welded body design, low operating torque, and excellent sealing capability, it provides safe and efficient flow control for oil & gas, LNG, and petrochemical systems.

Through advanced manufacturing technology, professional engineering support, and strict quality management, J-VALVES delivers high-performance welded trunnion mounted ball valves designed for demanding industrial applications worldwide.

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Top entry trunnion mounted ball valve with a one piece body that removes the bolted body joint from the pressure boundary. Seats and seals are serviced through the top cover without cutting the valve out of the pipeline. Nominal Size: 1 inch to 36 inch Pressure Class: ASME Class 150 to 2500 Body Material: WCB, LCC, CF8M, CF3M, A105 forged Body Style: One piece top entry Ball & Stem: CF8M or F316 with ENP coating Seat Material: PTFE, RPTFE, PEEK or metal End Connection: Flanged RF / RTJ, butt weld Operation: Gear, pneumatic or electric actuator Maintenance: In line, through the top cover Design Standard: API 6D / ISO 14313 Test Standard: API 598, API 607 fire safe Options: Sealant injection, cavity relief, extended stem
A high pressure trunnion mounted ball valve for Class 900 to 2500 service, built to API 6D PSL3 with a forged or cast body, spring loaded seats, double block and bleed and sealant injection ports. Suited to wellheads, gas gathering and high pressure process isolation.   Nominal Size: 2 inch to 24 inch (DN50 to DN600) Pressure Class: ASME Class 900 / 1500 / 2500 Body Material: A105 forged, WCB cast, A182 F316, F51 duplex Ball & Stem: A182 F316 with ENP or hard chrome Seat Material: PTFE, RPTFE, PEEK or metal to metal End Connection: Flanged RF / RTJ, butt weld, hub Operation: Gear, pneumatic or electric actuator Design Standard: API 6D / ISO 14313, ASME B16.34 Test Standard: API 598, shell 1.5x and seat 1.1x Fire Safe: API 607 / API 6FA Material Certificate: EN 10204 3.1 with heat number traceability Temperature Range: -29 C to +200 C, trim dependent
Nominal Size :3/4"~60" (DN20~DN1500) Pressure Class :150LB~2500LB (PN10~PN420) Temperature Range: -20℃ ~ +200℃ Body Material :C95800 Nickel Aluminum Bronze Ball Material :C95800 Nickel Aluminum Bronze Stem Material :C95800 Nickel Aluminum Bronze Seat Material :PTFE, RPTFE, PEEK End Connection :Flanged RF Operation: Manual (Lever / Gear), Pneumatic, Electric Design Standard: ASME B16.34, API 608 Test Standard: API 598, ISO 5208 Face to Face: ASME B16.10 Fire Safe Standard: API 607
Nominal Diameter: 0.5" (DN15) Pressure Class: Class 300 (PN50) Temperature Range: -29℃ to +425℃ Body / Bonnet: ASTM A216 WCB cast carbon steel Ball: A105N / WCB with hard chrome plating, or 304 / 316 stainless steel (optional) Stem: 410 / 420 stainless steel or 17-4PH precipitation hardening stainless steel Seat: PTFE, RPTFE, PPL (reinforced PTFE) Sealing Materials: PTFE / RPTFE / PPL (seat), flexible graphite or PTFE (stem packing) End Connection: Flanged (RF Raised Face, conforming to ASME B16.5) Operation: Lever (90° open/close, with optional locking hole) Design Standards: ASME B16.34, API 608 Inspection & Test Standard: API 598 Face-to-Face Dimension: In accordance with ASME B16.10