Trunnion Ball Valve

We design and manufacture trunnion ball valves for pipelines and process systems that operate under demanding pressure and flow conditions. SVR Global  valves are built to hold their seal across thousands of operating cycles, in sizes ranging from small bore isolation points to large diameter transmission lines. Every valve leaving our facility is tested against the standard it's rated for, so what you install matches what you specified. 

Types of trunnion ball valve:

• Casting trunnion ball valve - Body formed by pouring molten metal into a mold, suited for larger sizes and complex shapes.

• Forged trunnion ball valve - Body shaped from solid metal under pressure, giving higher strength for smaller, high pressure sizes.

Working mechanism of trunnion ball valve:

• Open position - the ball's bore lines up with the pipe axis, so fluid flows straight through with minimal restriction.

• Turning the stem - rotating the handle 90° turns the top trunnion, which rotates the ball.

• Closed position - the bore is now perpendicular to flow, so the solid part of the ball blocks the passage.

• Sealing - throughout this rotation, the ball never shifts sideways (unlike a floating ball valve) because the top and bottom trunnions hold it in a fixed axis. The spring loaded seats do the sealing work by pressing against the ball's surface, so shutoff quality doesn't depend on line pressure.

Dimensional and Design Standards:

• Face to Face Dimensions: ASME B16.10

• Flange Dimensions and Ratings: ASME B16.5 (Class 150-2500), ASME B16.47 (large diameter flanges)

• Pressure Temperature Ratings: ASME B16.34

• Butt Weld End Preparation: ASME B16.25

• Design, Inspection, and Testing: API 6D

• Fire Type Testing: API 6FA, API 607

• Wall Thickness (Steel Valves): API 6D / ASME B16.34 minimum wall requirements

Trunnion Ball Valve Specifications:

Testing & Inspection Methods:

• Shell Test - Confirms the valve body withstands rated pressure without leakage through the wall or joints.

• Seat Test - Checks each seat individually for leakage past the ball, per API 598 criteria.

• High Pressure Gas Test - Verifies gas tight shutoff at tighter leakage limits than standard liquid testing.

• Fire Type Testing - Confirms the metal seat holds shutoff after fire exposure, per API 607 / API 6FA.

• Cryogenic Testing - Verifies seal integrity at low temperature for cryogenic and gas transfer service.

• Non Destructive Examination (NDE) - Castings, forgings, and welds are inspected via RT, UT, MPI, or PT based on material and pressure class.

Quality Assurance & Certifications:

• API 6D / API 607 Certified

• ISO 9001:2015

• Fire Safe Design (API 607 / API 6FA)

• Third Party Inspection (TPI)

Trunnion ball valve applications:

• Oil & gas transmission pipelines

• Petrochemical process plants

• Power generation (steam, feedwater, cooling water lines)

• Water treatment and distribution systems

• Marine and shipbuilding piping systems

• Subsea and offshore piping systems

• Terminal and storage facility isolation

• LNG and cryogenic transfer lines

Custom Manufacturing & OEM Solutions:

• Beyond standard catalog sizes, we build valves to custom bore profiles, non-standard end to end dimensions, and specific trim combinations for buyers replacing legacy equipment or matching an existing piping spec. 

• OEM orders are built to the buyer's drawing package, with private labeling and packaging available for resale or private brand distribution.