Large pipelines demand more than a standard isolation valve. They require dependable shut-off performance, stable operation under pressure, and a configuration that matches the project’s medium, temperature, connection, and operating requirements. A trunnion mounted ball valve is designed for these demanding applications.
At GMK VALVE CO., LTD., we manufacture industrial ball valves for oil and gas, petrochemical, power generation, pipeline transportation, and other process applications. The large-bore valves shown in this article demonstrate the scale of projects that require carefully engineered valve solutions.
What Is a Trunnion Mounted Ball Valve?
A trunnion mounted ball valve is a quarter-turn isolation valve in which the ball is mechanically supported by upper and lower trunnions. Unlike a floating ball design, the ball remains supported while the seats move toward the ball under line pressure. This structure is especially suitable for larger diameters and higher-pressure services.
During operation, the ball rotates 90 degrees between the fully open and fully closed positions. When open, a full-port design can provide a streamlined flow path. When closed, the seats engage with the ball to isolate the pipeline. This delivers stable ball support and practical on/off isolation for demanding pipeline duties.
Why Large-Bore Pipelines Need a Trunnion Design
As valve diameter and pressure class increase, the forces acting on internal components also increase. A trunnion-mounted structure supports the ball at both ends and transfers pressure-related loads through the trunnion bearings. This design helps reduce unnecessary friction between the ball and seats during operation.
For buyers, EPC contractors, and project engineers, a trunnion mounted ball valve can offer several practical benefits:
- Stable ball support for large-size valve configurations
- Reduced operating torque compared with an equivalent floating-ball design
- Suitability for manual gear operation or automated actuation
- Reliable on/off isolation for high-pressure pipeline duties
- Flexible material, end-connection, and seat-design selection
Large-Diameter Ball Valve Configurations from GMK
GMK supplies trunnion-mounted ball valves in a broad range of sizes, pressure classes, materials, and connection types. Our standard product range includes sizes from DN50 to DN1000, with pressure ratings from Class 150 through Class 1500.
The manufacturing photos in this article include large valve assemblies marked with configurations such as 36-inch Class 600 WCB and Class 900 low-temperature carbon steel material. For special projects, the final valve configuration should always be confirmed against the customer’s specification and applicable engineering requirements.
Material Options
Material selection should match the design temperature, process medium, corrosion conditions, and project standard. GMK can provide carbon steel, low-temperature carbon steel, stainless steel, alloy steel, and selected corrosion-resistant alloy options.
Common options include WCB, LCB, LCC, WC6, WC9, CF8, CF8M, CF3, CF3M, Alloy 20, Hastelloy C, and others according to project requirements.
End Connections and Operation
Available end connections may include RF flanges, RTJ flanges, butt-weld ends, hub ends, and groove connections. Operating options can include gear operator, pneumatic actuator, electric actuator, or hydraulic actuator, depending on valve size and project requirements.
Key Design Features to Consider
A large-bore trunnion mounted ball valve is not selected by size and pressure rating alone. Several design features should be reviewed during technical evaluation.
Full-Port Flow Path
A full-port configuration is commonly selected when low pressure loss, pigging compatibility, or unrestricted flow is important. The final bore requirement should be confirmed in the project data sheet.
Seat Design and Sealing Performance
Seat design is central to isolation performance. Depending on service conditions, the valve can be configured with soft seats, metal seats, spring-assisted seats, or other project-specific sealing arrangements. Buyers should clearly state the fluid, operating pressure, temperature range, and requirements for fugitive emissions or fire-safe performance.
Stem and Safety Features
For industrial service, specifications may call for a blowout-proof stem, anti-static device, and fire-safe design. GMK can review these requirements during quotation to help align valve construction with the relevant project standard.
Applicable Standards
Depending on the valve configuration and customer specification, GMK trunnion-mounted ball valves can be supplied in accordance with standards such as API 6D, API 608, ASME B16.34, API 598, API 607, API 6FA, ASME B16.5, ASME B16.47, and ASME B16.25.
For more information about international valve standards, visit the API standards resource.
It is important to confirm the applicable standard, inspection level, test requirements, documentation package, and third-party inspection requirement before production. This helps ensure that the final valve is aligned with the project’s technical requirements.
How to Request a Quotation
To receive an accurate quotation for a trunnion mounted ball valve, please provide the following information:
- Valve size and pressure class
- Process medium and design temperature
- Body, ball, stem, and seat material requirements
- End connection type
- Manual, pneumatic, electric, or hydraulic operation
- Applicable standards and inspection requirements
- Required documents, coating, packaging, and delivery destination
Talk to GMK About Your Ball Valve Requirement
GMK VALVE CO., LTD. supports customers with industrial valve solutions for demanding pipeline and process applications. Whether you require a standard trunnion-mounted ball valve or a large-bore, project-specific configuration, our team can review your specification and provide technical support.
Explore GMK’s complete industrial valve portfolio and contact our team for project-specific support.
Website: https://www.valve-gmk.com/
Email: sales@gmkvalve.com | info@gmkvalve.com
WhatsApp: +86 138 5773 4602
