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- API 603 — Corrosion-Resistant, Bolted Bonnet Gate Valves — Flanged and Butt-Welding Ends
- API 603 — Corrosion-Resistant, Bolted Bonnet Gate Valves — Flanged and Butt-Welding Ends
API 603 — Corrosion-Resistant, Bolted Bonnet Gate Valves — Flanged and Butt-Welding Ends
API 600 for corrosive service. Same bolted-bonnet discipline, applied to austenitic stainless and duplex bodies where the medium, not the pressure, is the design driver.
API 603 covers Class 150, 300 and 600 gate valves in corrosion-resistant materials — CF8, CF8M, CF3, CF3M and the duplex and super duplex grades — with flanged or butt-weld ends. It follows the same construction philosophy as API 600 but with wall thickness and seating requirements tuned to austenitic castings.
The distinction from API 600 matters in practice: API 600 covers carbon and low-alloy bodies as well as stainless, but its minimum wall and seat geometry are optimised for the pressure-retaining case. On a chemical line where the governing requirement is corrosion allowance and chloride resistance, API 603 is the correct call-out.
We supply API 603 gate valves in CF8M and CF3M as standard, with duplex and super duplex to order, and with the same backseat and packing serviceability as the carbon steel line.
Coverage
- NPS 1 – NPS 12 typical, larger on request
- Class 150, 300, 600
- Bolted bonnet, OS&Y, rising stem, backseat
- CF8, CF8M, CF3, CF3M, duplex, super duplex
- Flanged RF/FF and butt-weld ends
- Tested to API 598
Related standards
Send the piping class, not the part number
We check the dimensions, the material and the standard before we price — which is the part that decides whether the valve actually fits. RFQ answered within one working day.