SEBIM®
GVG 3000 Main steam safety valve
The SEBIM® POSV type GVG 3000 is designed for overpressure protection of the nuclear steam supply system in all designs of nuclear reactors.
The SEBIM® POSV GVG series was developed for overpressure protection of the steam generator or the main steam lines of all designs of nuclear reactor. The GVG series is the tubeless design of the previous SGSV series and uses some tubing interface with piloting systems in operation since the 1990’s.
MAIN CHARACTERISTICS
- Autonomous piloting system using the fluid in the protected process (no external source of energy is needed for operation)
- No-Flow piloting system
- Compact & tubeless design (drilling integral through valve body; reduced size & weight)
- Excellent leak tightness (the disc and the nozzle are leak tight up to the point of opening and immediately again after closing)
- No erosion of sealing faces; no chattering
- Proven perfect repeatability and reliability
- System insensitive to back pressure
- Stable system: no mass spring effect
APPLICATIONS
- Steam Generator Safety Valves
- Main Steam Lines Safety Valves
DESIGN RATINGS
- ASME Class 150 to 2500 or customized
PRESSURE CLASS & POWER
- 43 – 2,900 psi (0.3 – 20 Mpa)
- 393 T/h – 5,6 Mpa (Saturated Steam) adaptable
MATERIALS
- Stainless steel
- Carbon Steel
- Special materials upon request
UPGRADES & ADAPTATIONS
- Interface adaptable to the need
KEY FEATURES & BENEFITS
- Excellent operation irrespective of fluid type; steam, gas, liquid or two-phase
- Leak tightness up to the set-pressure minimises the mechanisms rate of ageing
- Non-flowing pilot valve minimises the mechanisms rate of ageing
- Proven reliability
- Excellent accuracy (better than 1%)
- Repeatability (lower than 1%)
- Soft opening/closing decreases load on surrounding equipment
- Low or high pressure in-situ test during operation for preventative maintenance
- In situ testing with or without pressure in the protected system
- Maintained stability even when flow capacity is below the maximum rate
- Reduced maintenance over a 10 years operating cycle
- Tubeless design
DESIGN STANDARDS
- All main standards including RCC-M level 2, ASME section III Sub.NB Class 2, OTT, IEEE, NNSA
SIZE RANGE & DIMENSIONS
- 0.5 – 16 inches (15 – 400mm) (DN 25 – DN400)
TEMPERATURE RANGE
- Up to 576°C (1069°F)
