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350×500 High-Capacity Steam Pressure Relief Valve (PRV)
Complete Specifications, Compliance Standards & Industrial Applications
Steam Pressure Relief Valves (PRVs) are mission-critical safety components in industrial steam and fluid systems. They protect equipment, pipelines, and personnel from overpressure events that may result in mechanical failure, unplanned downtime, or catastrophic accidents.
Among large-format safety valves, the 350×500 high-capacity steam PRV is engineered for extreme operating conditions, offering exceptional flow capacity, thermal resilience, and full regulatory compliance. This article provides a structured overview of its technical specifications, operating performance, and primary industrial applications.
Core Technical Specifications & Performance Parameters
1. Port Size & Dimensional Configuration
- Inlet Diameter: 350 mm (14 in)
- Outlet Diameter: 500 mm (20 in)
- Flange Standard: ANSI Class 300 (custom options available)
The oversized inlet and outlet configuration minimizes flow restriction and ensures rapid pressure relief in large-scale steam systems.
2. Set Pressure Range & Pressure Rating
- Adjustable Set Pressure: 1.0 – 20 bar (14.5 – 290 psi)
- MAWP: 25 bar at 300 °C
- Pressure Accuracy: ±2% of set pressure
Custom calibrations are available for both low-pressure and high-pressure applications in accordance with ASME BPVC requirements.
3. Temperature Capability
- Continuous Operation: ≤ 300 °C (572 °F)
- Short-Term Upset: 350 °C for up to 2 hours
Designed to prevent thermal fatigue, seat deformation, and material degradation in high-temperature steam service.
4. Reseating & Blowdown Characteristics
- Reseating Pressure: 89% of set pressure
- Blowdown: Approx. 11%
- Seat Tightness: ANSI/FCI 70-2 Class V
Rapid reseating minimizes steam loss and improves overall energy efficiency.
5. Materials & Mechanical Construction
- Body: 316L stainless steel (duplex optional)
- Trim: Stellite-hardened disc and seat
- Construction: Forged body
Forged construction ensures superior fatigue resistance and structural integrity in high-pressure, high-temperature environments.
6. Flow Capacity
- Typical Flow: Up to 50,000 kg/h (steam at 20 bar, 300 °C)
- Cv Value: Approx. 1200
Engineered for high-discharge conditions in boilers, turbine bypass systems, and refinery steam headers.
7. Compliance & Certification
- ASME BPVC Section I & VIII
- ISO 4126-1
- API 526
- CE PED 2014/68/EU
- ISO 9001:2015 Manufacturing
Fully compliant with international pressure equipment and process safety regulations.
Industrial Application Scenarios
Power Generation
Applied on boilers and turbine protection systems to relieve excess pressure during load transients, start-ups, and emergency events. Enhances turbine protection, improves thermal efficiency, and reduces forced outages.
Chemical & Petrochemical Processing
Installed on reactors, heat exchangers, and distillation columns to stabilize pressure in corrosive and high-temperature processes while maintaining compliance with OSHA and ISO safety frameworks.
Industrial Boilers & Central HVAC
Used in hospitals, manufacturing plants, and district heating systems to protect boilers and distribution networks, lowering fuel consumption and extending equipment service life.
Oil & Gas Refineries
Provides overpressure protection for steam-driven pumps, compressors, and cracking units in HPHT refinery environments, supporting continuous and safe operation.
Food & Beverage Processing
Controls steam pressure in sterilization and pasteurization systems. 316L stainless steel ensures hygienic performance and easy cleaning in food-grade applications.
Conclusion
The 350×500 high-capacity steam pressure relief valve integrates high flow capacity, precise pressure control, advanced metallurgy, and full international certification. It is a proven solution for power generation, chemical processing, oil & gas, HVAC, and food-grade steam systems where safety and reliability are paramount.
For optimal performance, valve selection should be based on actual operating pressure, temperature, steam flow rate, and regulatory requirements. Partnering with an experienced industrial valve supplier ensures correct sizing, compliance, and long-term operational reliability.
Contact our engineering team for sizing calculations, drawings, and application-specific configurations tailored to your steam system.
