Ball Valve

Large Bore Trunnion Mounted Ball Valve — Hydraulic Actuated Heavy Duty Pipeline Service

Specification

Valve Type

Size Range

DN600 – DN2000 (24" – 80")

Pressure Class

PN16 – PN100 (Class 150 – 600)

Body Material

WCB / WC6 / LCB / CF8M / F51 Duplex

Seat Material

PTFE / RPTFE / Metal Seat (Stellite Overlay)

End Connections

Flanged (ASME B16.47 / EN 1092-1) / Butt Weld

Operation

Hydraulic Actuator / Pneumatic Actuator / Electric Actuator / Gear Operator

Working Temperature

−46°C to 200°C (PTFE Seat) / up to 425°C (Metal Seat)

Design Standard

API 6D / ASME B16.34 / ISO 14313

Details

HD Flowtech large bore trunnion mounted ball valves are engineered for full-bore isolation service in large-diameter water transmission, hydropower, industrial water supply, and heavy-duty pipeline systems requiring high output actuation force and comprehensive auxiliary system integration. The heavy-duty carbon steel cast body with blue epoxy coating provides long-term corrosion protection and structural integrity for large-bore above-ground pipeline installations. The trunnion-supported ball design transfers high pipeline pressure loads to the trunnion bearings, maintaining consistent low-torque actuation and stable sealing performance at large bore sizes where floating ball designs would generate impractical seat loads and operating torques. The hydraulic cylinder actuator provides the high output thrust required for reliable quarter-turn actuation on large-bore heavy-duty service — hydraulic actuation is the preferred choice for very large valves where pneumatic and electric actuators cannot generate sufficient force for reliable operation under full differential pressure. A comprehensive auxiliary piping system — visible as multiple small-bore stainless steel lines connecting to body ports — provides seat and stem seal lubrication injection, cavity drain and vent connections, pressure equalization lines, and instrumentation connections for continuous valve condition monitoring. Heavy-duty foundation support brackets with anchor bolt provisions provide stable structural mounting for the large valve assembly mass. Flanged end connections to ASME B16.47 large-bore flange standard ensure direct integration into large-diameter pipeline flange systems.

Ball Valve Technical Overview

How to Choose the Right Ball Valve for Industrial Applications

Large bore trunnion mounted ball valves with hydraulic actuation are selected for full-bore isolation service in large-diameter water transmission mains, hydropower station inlet isolation, industrial cooling water systems, and heavy-duty process pipelines where the high output force requirements of large-bore actuation under full differential pressure exceed the practical capability of pneumatic and electric actuator designs. Hydraulic actuation provides the highest output force-to-actuator-size ratio of any actuation method — making it the standard choice for ball valves above DN600 in high-pressure service where reliable operation under maximum differential pressure must be guaranteed throughout the valve’s service life.

Comprehensive auxiliary piping systems are standard for large bore trunnion mounted ball valves, providing seat seal lubrication injection to maintain sealing performance and reduce operating torque over extended service cycles, stem packing lubrication for consistent stem seal integrity, cavity drain and vent connections for controlled depressurization during maintenance, and pressure equalization lines for assisted opening under high differential pressure conditions. These auxiliary systems extend valve service life and reduce maintenance intervals in large-bore installations where valve removal and overhaul are costly and operationally disruptive.

Trunnion mounted construction is mandatory for large-bore ball valves at DN600 and above, where the trunnion support is essential for managing the mechanical loads generated by pipeline pressure against the large ball area — loads that would produce impractical seat contact pressures and actuator torques in floating ball designs. Body material selection — WCB for standard water and process service, LCB for cold climate service, and duplex grades for corrosive applications — is determined by fluid type, operating temperature, and pipeline service requirements. Design standard API 6D governs trunnion mounted ball valves for pipeline service, with ASME B16.34 applying for pressure-temperature ratings across all material grades and bore sizes.