Description

Technical Data Sheet

3-Piece Trunnion Mounted Ball Valve

Model: Q347F / 3PC-Trunnion Series / API 6D Compliant

1. Product Overview

This 3-piece trunnion mounted ball valve combines the maintenance-friendly features of a three-piece body design with the high-pressure capabilities of trunnion mounting. The valve body consists of three forged or cast sections bolted together, allowing for easy removal of the center section for maintenance without disturbing the pipeline ends. The trunnion-mounted ball provides stable operation under high differential pressure and reduces operating torque .

2. Design Standards & Specifications

3. General Specifications

4. Material Specifications (Forged Steel Series)

5. Key Design Features

• 3-Piece Bolted Body Construction: The valve consists of three separate body sections bolted together. This design allows for in-line maintenance where the center section (containing ball and seats) can be removed without disturbing the pipeline ends . The bolted construction also accommodates various end connection types on the same center section .

• Trunnion Mounted Ball: The ball is supported by two fixed trunnion shafts with bearings, eliminating seat loading under high differential pressure. This reduces operating torque by up to 60% compared to floating ball valves at Class 600+ .

• Dual Seat Design: Primary soft seat (PTFE/PEEK) provides zero-leakage sealing during normal operation. Secondary metal seat (Inconel/Stellite) serves as an emergency backup in case of fire or soft seat failure, meeting API 607/6FA fire-safe requirements .

• Double Block & Bleed (DBB) Capability: The valve seals against pressure from both directions simultaneously, allowing the body cavity to be vented to confirm seal integrity per API 6D requirements .

• Blowout-Proof Stem: The stem is internally retained by the body, ensuring it cannot be ejected by line pressure even if the packing gland is removed .

• Anti-Static Device: Spring-loaded plungers or contacts ensure electrical continuity between the ball, stem, and body (resistance ≤10Ω), preventing static charge accumulation .

• Cavity Pressure Relief: An optional relief hole in the ball (upstream side) prevents pressure buildup in the body cavity due to thermal expansion .

• Forged Components: Pressure-containing parts are forged, providing superior grain structure, strength, and material traceability compared to castings .

• ISO 5211 Mounting Pad: Integral top flange allows direct mounting of actuators without brackets .

6. Seat Design Options

7. Performance Data

8. Principal Dimensions (Reference – Class 150 Flanged)

Note: Dimensions are for reference only. Final dimensions to be confirmed based on manufacturer’s detailed drawing and pressure class.

Source:

9. Applications

• Oil & Gas: Pipeline transmission, production manifolds, wellhead equipment

• Refining: Hydrocracking, catalytic reforming, high-temperature hydrocarbon services

• Petrochemical: Ethylene, propylene, and other process plants

• Power Generation: Steam, feedwater, and fuel systems

• LNG & Cryogenic: Liquefied natural gas, air separation units (with extended bonnet)

• Offshore: Platform piping systems, subsea applications (with special coatings)

• Industrial: High-pressure water, steam, and corrosive media

10. Testing & Certification

Each valve shall be manufactured, tested, and certified in accordance with:

1. Material Test Certificates (MTC): EN 10204 Type 3.1 or 3.2 certification for pressure-containing parts

2. Hydrostatic Testing: Shell and seat test reports per API 598

3. Fire-Safe Certification: API 607 / API 6FA type test certificate

4. Fugitive Emissions Test: ISO 15848-1 certificate (if specified)

5. NACE Compliance: Statement of compliance with NACE MR0175

6. NDE (Non-Destructive Examination):

   • Visual inspection (VT)

   • Radiographic (RT) or Ultrasonic (UT) examination on castings/forgings (as required)

   • Dye Penetrant (PT) or Magnetic Particle (MT) on critical welds

7. SIL Rating: Safety Integrity Level certification (if required)

11. Ordering Information

Please specify the following to ensure correct valve selection:

1. Size & Pressure Rating: (e.g., 8″ – Class 600)

2. Body Material: (e.g., Forged A105N, F316, LF2)

3. End Connections: (Flanged RF/RTJ, Butt-Weld, Socket Weld)

4. Bore: Full Bore or Reduced Bore

5. Seat/Trim Material: (RPTFE, PEEK, Metal seats with temperature range)

6. Seat Design: DPE, SPE, or Mixed (if special requirement)

7. Operation: Manual (Gear), Pneumatic, Electric (specify voltage/control)

8. Special Requirements: Fire-safe, NACE, Cryogenic, Fugitive Emissions, SIL

9. Certifications: API monogram, PED, ATEX, etc.