Pressure Vessel Safety Valves — ASME VIII Certified
Every ASME Section VIII unfired pressure vessel requires certified relief valve protection sized for the vessel’s maximum allowable working pressure (MAWP) and intended duty. Aquatrol manufactures ASME Section VIII certified relief valves with third-party capacity testing and documentation for compliance with Code, insurance, and regulatory requirements.
Pressure Vessel Relief Valve Requirements
ASME Section VIII mandates relief valve protection for all unfired pressure vessels holding steam, gas, liquid, or mixtures under pressure. The valve must be certified, sized for the vessel MAWP and volume, and include documentation proving compliance. Failure to properly protect a vessel can result in catastrophic failure, regulatory fines, and safety liability.
Vessel relief sizing is distinct from boiler sizing because the vessel stores pre-generated pressure rather than continuously generating it. Relief capacity depends on vessel volume, operating pressure, and media type. Our engineers calculate the correct capacity based on your vessel specifications and provide third-party test documentation proving compliance.
Installation location and configuration matter. Relief valves must be mounted directly on or adjacent to the vessel, with proper isolation and vent piping. Sizing for the specific inlet and outlet configuration (NPT, flanged, tri-clamp) ensures proper flow and pressure response. Our technical team guides installation and can coordinate with your inspector.
| Vessel Type | Series | Pressure Rating | Media |
|---|---|---|---|
| Air receiver | 55, 140 | 150–300 PSIG | Compressed air |
| Steam accumulator | 69, 55 | 50–1,500 PSIG | Steam |
| Thermal tank | 135, 570 | 50–300 PSIG | Water, glycol |
| Cryogenic tank | 560 | 30–1,000 PSIG | LNG, nitrogen |
| Process vessel | 55, 120, 741 | 50–2,000 PSIG | Liquids, gases, food |
Common Applications
- Air receiver tank relief and OSHA compliance
- Steam accumulator and surge tank protection
- Cryogenic and low-temperature vessel relief
- Thermal expansion tank overpressure relief
- Industrial process vessel safety limiting
- Food and pharma tank relief (sanitary designs)
- Gas cylinder and storage tank pressure limiting
Need Help Choosing the Right Valve?
Our valve engineers can help you select the perfect valve for your application.