Product - VBSE High Pressure Turbine Bypass Valve
​​​​​​​​The VBSE is a steam conditioning valve used for steam throttling and desuperheating
through spray water injection, directly at the outlet. Used for start-ups and load reje​​ction, they bypass the steam to various reheat lines until the steam temperature matches the turbine blade temperature.

With a range of available body materials, the VBSE valve can be used for the main steam pressures and temperatures of today’s most advanced single and double reheat thermal power plants.

​​Key Features

  • Specially designed for modern ultra-supercritical power plants load ramping and trip case requirement
  • Forged body design with flow-to-close flow pattern
  • Pressurised seal bonnet design allowing for greater reliability at high pressures
  • Can be equipped with hydraulic, electromechanical or pneumatic actuator.
  • Seal welded seat with integral first stage pressure reduction tube allowing for quick maintenance a​nd replaceable features
  • Spring loaded water injection nozzles
  • Integral inlet nozzle upon request
  • Different plug designs available


  • Compact and robust design with more standardised components
  • Reduced number of components
  • Easy maintenance features allowing quick access to internals and pressure reduction tube
  • Inlet bonnet cage with drilled hole pattern to reduce the level of noise emission
  • No need for special tools for assembly/dissasembly
  • Exchangeable trim
  • Pilot plug design allowing for Class V / MSS SP 61 shut-off class
  • Outlet expansion for improved mixing and atomisation
  • Modular design to meet all customer demands

​​Product Specification

Body style
Forged angle type valve body, flow direction - flow-to-close

Nozzle connection
For steam pipes: butt-welding, according to customer’s requirement
For spray water pipes: butt-welding, according to customer’s requirement

Trim design
Welded seat ring, pilot operate​d trim

Steam data
Temperature range: up to 630°C
Inlet pressure: up to 350 bar

Seat leakage class
EN 12266-1 Cl. B or MSS-SP61 or ANSI/ FCI 70.2 Cl. V


Hydraulic, electric or pneumatic actuator

All internal trim parts, seat ring (welded), spray nozzles

Transition pieces for large pipe diameters and material compatibility.
Prewarming and/or drain connection available upon request
Integral inlet upon request

Certified acc. to PED 2014/68/EU

Design code
EN 12516-2, others upon request​

​Application Example​

​​Valve Breakdown​

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Product - VBSE High Pressure Turbine Bypass Valve