2-1/2″ Class 150 API 6D Trunnion Ball Valve – F304 Body
2-1/2″ (DN65) Class 150 (PN20) RF Flanged API 6D Trunnion Mounted Ball Valve (F304 Body, 2-Piece Cast Split Body). Engineered with spring-energized RPTFE soft seats, Double Block and Bleed (DBB) isolation, automatic cavity pressure relief (SPE), dual emergency sealant injection, API 607 fire-safe certification, and ISO 15848-1 Class AH low-emission packing.
Description
The NPS 2-1/2″ Class 150 RF API 6D Trunnion Mounted Ball Valve (F304) is an engineered severe-service pipeline isolation valve manufactured by XIAMEN GUTE VALVE MANUFACTURING COMPANY. Designed in full compliance with API 6D, ASME B16.34, and ISO 14313, it features an anchored trunnion ball mechanism supported by heavy-duty composite sleeve bearings that absorb pipeline hydraulic thrust to minimize operating breakaway torque. Incorporating independent spring-energized floating seats, Double Block and Bleed (DBB) cavity isolation, automatic thermal cavity relief, and certified fire-safe secondary metal seating, it delivers zero-leakage pipeline integrity across high-pressure hydrocarbon transport, refinery manifolds, and critical process piping.
Engineering Configuration & Dimensional Specifications
NPS 2-1/2″ (DN65) | Class 150 (PN20) | F304 Body | RF Flanged | 2-Piece Cast Split Body | API 6D
- Face-to-Face Dimension (L): 190 mm (ASME B16.10 / API 6D Table 1)
- Center-to-Stem Top Height (H): 180 mm
- Operating Breakaway Torque: ~95 N·m (Calculated at maximum differential pressure ΔP)
- Bare-Stem Assembly Weight: ~32 kg
- Actuation Interface: Lever (Handle) (Standardized ISO 5211 direct mounting pad configured for automation)
- Cavity Sealing Architecture: Independent spring-energized floating seats with DBB functionality & automatic thermal relief
Core Structural Architecture: Trunnion Support & Dual-Sealing Dynamics
The mechanical trunnion design anchors the ball between the upper drive stem and the lower trunnion support shaft, completely preventing lateral ball displacement under severe hydraulic loads. Operating torque is transferred directly into the heavy-wall body matrix rather than compressing the downstream seat.
- Double Block & Bleed (DBB): Upstream and downstream seat rings seal independently against the ball under spring pre-load and line pressure. Opening the central body bleed valve allows cavity venting and verification of seat integrity without interrupting pipeline operation.
- Automatic Cavity Pressure Relief (SPE): When thermal expansion of trapped cavity liquid increases internal body pressure by 1.0–1.5 bar above line pressure, the seat rings are pushed back against the springs, discharging overpressure safely into the line.
- Emergency Sealant Injection System: Dedicated secondary sealant injection fittings equipped with internal check valves are provided at both seat rings and stem journals, enabling emergency seal restoration under full line pressure.
Rigorous Quality Assurance & API 6D Inspection Protocols
- 1. Material Traceability & PMI: 100% Positive Material Identification (PMI) spectroscopic verification on all pressure-retaining heats with certified EN 10204 3.1 Mill Test Reports (MTR).
- 2. Hydrostatic Shell & Seat Integrity Testing: Hydrostatic shell test at 1.5x CWP, high-pressure closure test at 1.1x CWP, and low-pressure air seat test at 6 bar per API 6D / API 598 (Rate A Zero Leakage).
- 3. Double Block and Bleed (DBB) Verification: Independent verification of both upstream and downstream seat tightness under full differential pressure.
- 4. Fire-Safe Certified Construction: Rigorously tested and qualified in compliance with API 607 (7th Edition) and API 6FA fire-safe standards.
- 5. Non-Destructive Examination (NDE): Radiographic (RT), Ultrasonic (UT), and Dye Penetrant (PT) examination on critical casting and forging sections per ASME B16.34.
Frequently Asked Technical Questions
A: In floating ball valves, the line fluid pushes the unrestricted ball downstream into the resilient seat, causing operating torque to scale exponentially with pipeline pressure. In this Gute NPS 2-1/2″ Class 150 trunnion ball valve, the ball is permanently anchored by upper drive and lower trunnion shafts supported by PTFE-lined composite sleeve bearings. Hydraulic line thrust is absorbed directly by the body matrix, leaving operating torque (~95 N·m) governed solely by spring-assisted floating seat contact. This design cuts actuator sizing requirements by over 50% and eliminates seat ovalization.
A: The F304 stainless steel matrix provides total immunity to oxidation, nitric/organic acids, and localized chloride pitting. For fugitive emission containment, the stem packing assembly utilizes precision die-formed flexible graphite packing rings supported by braided anti-extrusion wiper rings. Live-loaded with Inconel 718 Belleville spring washers, the packing maintains dynamic sealing under extreme thermal cycles, certified to ISO 15848-1 Class AH and German TA-Luft (< 100 ppmv leakage).
A: Every Gute trunnion valve complies with API 6D DBB definitions. With the valve fully closed and both upstream and downstream lines pressurized, the central body cavity bleed fitting can be opened to vent trapped fluid and verify seat tightness. Additionally, if foreign particulates cause minor seat scoring during pipeline commissioning, dedicated high-pressure injection fittings equipped with internal safety check valves permit emergency synthetic sealant injection directly into the seat contact groove under full working pressure.
Need Project-Specific Trunnion Ball Valve Sizing?
Contact Gute Valve technical engineering team for certified dimensional drawings, automated actuator sizing packages, NACE compliance documentation, or high-pressure DBB testing protocols.
Additional information
| Size | NPS 2-1/2″ |
|---|---|
| Pressure Class | Class 150 |
| Body Material | F304 |
| End Connection | RF |
| Material | |
| Pressure | |
| Valve Size | |
| Connection | |
| Design Standard | API Standard |
| Valve Type | |
| Operation | Lever (Handle) |
| Structure Detail | 2-Piece |
| Ball Material | 304 |
| Seat Material | RPTFE |
