Piping Class Reference
Piping Class A4A Valve Specification
Piping Class A4A covers ASME Class 900 carbon steel valves for very high-pressure hydrocarbon service — HP gas injection headers, wellhead flowlines, and high-pressure separator circuits. Class 900 valves use RTJ (Ring Type Joint) flange facing as standard; pressure-seal bonnets on gate and globe valves above DN50. Trunnion-mounted ball valves with metal seats and DBB (double-block-and-bleed) configuration are typical. Vajra Industrial Solutions supplies API 6D Class 900 trunnion ball valves, API 600 Class 900 gate valves, and Y-pattern globe valves to ONGC, HPCL, and EPC contractors for HP gas compression and wellhead isolation service. Full RTJ dimensional compliance per ASME B16.5 and API 6A documentation provided.
ASME Class
ASME Class 900
Design Pressure
148 bar (2149 psi)
Design Temperature
Up to 400°C (752°F)
Body Material
Carbon Steel ASTM
Design Parameters — A4A
Fluid Service
Very High Pressure — HP Gas Injection, HP Wellhead, Sour Gas to 148 bar
Design Pressure
148 bar (2149 psi)
Design Temperature
Up to 400°C (752°F)
Corrosion Allowance
3mm
Body Material
Carbon Steel ASTM A216 WCB / A105N Forged
Industries
HP gas injection, HP wellhead / Xmas tree
Valve Schedule — Piping Class A4A
| Valve Type | Rating | End Connection | Body Material | Trim | Seat/Sealing | Notes |
|---|---|---|---|---|---|---|
| Gate Valve | Class 900 | RTJ Flange (ASME B16.5) | A216 WCB | Stellite-6 HF | Stellite-6 HF | API 600, OS&Y, pressure-seal bonnet, RTJ facing |
| Globe Valve | Class 900 | RTJ Flange | A216 WCB | Stellite-6 HF | Stellite-6 HF | Y-pattern preferred; pressure-seal bonnet |
| Check Valve | Class 900 | RTJ Flange | A216 WCB | Stellite-6 HF | Stellite-6 HF | Tilting disc or piston lift; pressure-seal cover |
| Ball Valve | Class 900 | RTJ Flange | A216 WCB | Inconel 625 / SS 316 | Metal seat (tungsten carbide) | API 6D, trunnion, DBB, fire-safe, antistatic |
| Needle Valve | Class 900 | NPT/SW | A105 Forged | SS 316 | SS 316 / PTFE | Instrument isolation; HP block & bleed manifolds |
Typical Industries — A4A
Standard Certifications for A4A Valves
Shop Valves for Piping Class A4A
Related Piping Classes
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