How do turbine bypass valves work?
Turbine bypass valves use a multi-stage pressure‑reducing trim followed by integrated desuperheating spray nozzles to reduce steam pressure and temperature before directing it to a condenser or cold reheat line. They act instantly during turbine trips or start/stop cycles, ensuring safe steam diversion without damage.
Advantages of turbine bypass valves...
• Performs combined pressure reduction and desuperheating in one assembly
• Fast response to turbine trips and load changes
• Noise-attenuated trim designs (e.g. multi-stage/HUSH®)
• Tight shut-off (Class IV–V sealing)
• Easy in-line serviceability and modular trims
• Fast response to turbine trips and load changes
• Noise-attenuated trim designs (e.g. multi-stage/HUSH®)
• Tight shut-off (Class IV–V sealing)
• Easy in-line serviceability and modular trims
Technical Parameters:
Pressure Ratings
PN10, PN16, PN25, PN40, PN63, PN100, CL150, CL300, CL600, CL900, CL1500, CL2500, CL4500 (up to ASME Class 4500)
Temperature Range
Rated typically up to 630 °C (~1166 °F); capable of handling highest reheat steam temperatures (in excess of 600 °C)
Size Range
Common inlet sizes DN300–DN650 (NPS 12–26), outlets up to DN1500 (NPS 60). Some designs go to DN1200 or larger depending on custom applications
Materials
Carbon steel (A105), alloy steels (A182‑F22, F91, F92) for body and trims, with hard-faced Stellite overlays for wear resistance
Industry Application:
Nuclear
Power
Media Type:
Water
Steam
