Class 600 Globe Valve — ASTM A217 WC6 (1.25Cr-0.5Mo)
Y-pattern globe valve, Class 600, ASTM A217 WC6 body, bolted bonnet, OS&Y rising stem, butt weld ends, flexible graphite packing. NACE MR-01-75 compliant. High-temperature and sour service. Export to West Africa and Middle East.
The Class 600 Y-pattern globe valve in ASTM A217 WC6 (1.25%Cr-0.5%Mo) alloy steel is specified for high-temperature steam, hydrogen, and hot hydrocarbon service where carbon steel WCB reaches its creep range. The Y-pattern body geometry provides a straight-through flow path at a 45–60° angle, significantly reducing pressure drop compared to a conventional T-pattern globe valve, making it suitable for throttling and control applications at Class 600 pressure. The bolted bonnet with metal spiral-wound gasket (flexitallic type) provides a reliable pressure seal at temperature, while the flexible graphite packing with corrosion-inhibitor wiper rings eliminates steam leakage at the gland. NACE MR-01-75 (ISO 15156) compliance with hardness-controlled casting and trim is available for combined high-temperature sour service.
Technical Specifications
Features
- Y-pattern body: lower Cv loss (approx. 30% lower pressure drop than T-pattern) for throttling and flow control
- WC6 alloy: retains strength and oxidation resistance to 595°C (1100°F), suitable for steam and high-temperature hydrocarbon
- Bolted bonnet with spiral-wound gasket: no pressure-seal ring requirement at Class 600, easier maintenance
- Flexible graphite packing: fire-safe, low fugitive emissions, suitable for hot service and LDAR programmes
- NACE compliant hardness certificate included for sour service piping classes
- BW ends per ASME B16.25: schedule match on request (Sch 80, Sch 160, XXH)
Applications
High-pressure steam lines (Class 600 steam at 550°C+), hot hydrocarbon and hydrogen service in refineries, Cr-Mo piping circuits in boiler feed water and turbine extraction, sour high-temperature gas processing, and upstream wellhead/flowline systems where combined high-temperature sour service applies. Export to operators and EPC contractors in West Africa, Saudi Arabia, UAE, Oman, and India.
Related Products
Also see: Globe Valves Overview, NACE MR0175 Sour Service Valves, Pressure Seal Gate Valve.
Frequently Asked Questions
What is the difference between WC6 and WCB for a Class 600 globe valve?
ASTM A216 WCB (carbon steel) is the standard body material for Class 150–600 globe valves up to approximately 425°C. ASTM A217 WC6 (1.25Cr-0.5Mo) is specified when the service temperature exceeds 425°C or when elevated-temperature creep resistance is required — typically in steam, high-temperature hydrocarbon, and hydrogen service. WC6 also has better oxidation resistance than WCB above 480°C and is preferred in NACE sour service at elevated temperatures where WCB hardness control is marginal.
What NACE MR-01-75 requirements apply to a WC6 globe valve?
For NACE MR0175 compliance, ASTM A217 WC6 castings must be supplied in the normalised and tempered condition with a maximum hardness of 22 HRC (237 HB). Trim materials (disc, seat, stem) must also comply: F6 (13%Cr) stem and plug are permitted per NACE MR0175 Table B.3, and 316SS components are generally permitted. Hardness test certificates for all pressure-retaining parts are mandatory.
What pipe schedule can be accommodated for butt-weld ends on a Class 600 globe valve?
Butt-weld ends are furnished per ASME B16.25 end preparation geometry. For Class 600 alloy steel globe valves, the standard schedule for 2 inch NPS is typically Sch 80 or Sch 160 depending on the piping class. The valve manufacturer bores the BW end to match the inside diameter of the specified pipe schedule at the time of manufacture; confirm the required schedule (Sch 80, Sch 160, or XXH) in the purchase order.
Need Class 600 WC6 Globe Valves for High-Temperature or Sour Service?
Share your piping class sheet (valve data sheet) and we will confirm material, schedule match for BW ends, NACE compliance, and delivery. We export to refinery and petrochemical EPC projects in West Africa, the Middle East, and India.