ANSI Marine Gate Valve
Pressure and Temperature Ratings:
• Class 150: Max ~150 psi (10.3 bar) at ambient temperature. Suitable for low-pressure seawater, fuel, and water systems.
• Class 300: Max ~300 psi (20.7 bar). For medium-pressure systems.
• Class 800: Forged steel valves, often socket weld, for high-pressure small-bore lines.
• Class 1500: For very high-pressure applications, typically Chromoly or forged steel.
Temperature Limits by Material:
• Bronze: -20°C to 220°C (typically limited to ~200°C for continuous service).
• Carbon Steel (WCB): Up to 425°C.
• Stainless Steel (CF8/F304): Up to 600°C
Overview
Design and Manufacturing Standards:
ANSI marine gate valves are manufactured according to several key standards:
ASME B16.34 – The primary standard for valve design, governing pressure-temperature ratings, wall thickness, and material requirements. This is the most commonly cited "ANSI" standard for these valves.
API 600 / API 6D – Standards often referenced for heavier-duty marine gate valves, particularly for flanged valves in classes 150 to 600. These specify face-to-face dimensions (ANSI B16.10), flange dimensions (ANSI B16.5), and inspection/testing procedures (API 598).
API 602 – Used for smaller forged steel gate valves (typically socket weld or threaded ends) in classes 800 and 1500.
BS 5154 – A British Standard also commonly referenced for bronze gate valves, often alongside ASME B16.34.
Key Specification Parameters:
| Parameter | Typical Values / Options |
| Pressure Class | Class 125, 150, 300, 600, 800, 1500, 2500 (ASME/ANSI classes) |
| Nominal Size (DN / NPS) | DN15–DN400 (NPS ½"–16") for standard marine valves; larger sizes available for higher classes |
| Body Materials | Cast Iron, Bronze (ASTM B62), Aluminum Bronze, Carbon Steel (WCB), Stainless Steel (304SS, 316SS), Chromoly F11 |
| Trim Materials | Bronze, Monel, 13Cr, STL (Stellite), 2Cr13, F304/F316 |
| Connection Types | Flanged (ANSI B16.5), Threaded (NPT/BSPT), Socket Weld (ASME B16.11), Butt Weld (ASME B16.25) |
| Operation | Handwheel (OS&Y – Outside Screw & Yoke, rising stem; or non-rising stem) |
| Working Temperature | -20°C to 220°C (typical for bronze); up to 425°C for carbon steel; up to 600°C for stainless steel |
| Working Medium | Sea water, steam, oil, fuel, chemicals, natural gas |
| Design Standards | ASME B16.34, API 600, API 602, API 6D, BS 5154 |
| Face-to-Face | ANSI B16.10 |
| Flange Dimension | ANSI B16.5 |
| Inspection & Test | API 598, API 6D |
| Certification | LR, RINA, ABS, BV, CCS, DNV-GL (IACS members) |
