High-pressure turbine bypass valve

For steam redirection
This high-pressure turbine bypass valve, type SiRa BHsT from IMI B&R, is designed to redirect some or all steam from the main boiler away from the turbine and into the cold reheater line. The valve ensures controlled reduction of both pressure and temperature, allowing safe steam transfer between systems.

Advanced pressure and temperature control
Pressure reduction is achieved in multiple stages, with the valve stem precisely regulating the steam flow. Upon opening, part of the steam is also directed through an integrated pipe to the steam atomizing injection nozzle on the valve outlet side, ensuring optimal steam quality control.

Application and function
The valve is primarily used during plant startup and shutdown to protect the turbine, but it can also be used for continuous operation. Its robust construction and precise control ensure long service life and reliable performance under demanding conditions.

Technical specification
The valve can handle an inlet pressure of up to 320 bar[a] and temperatures up to 650°C. Connections are welded ends and customized to customer specifications.
The design features an angle body with a vertical stem and actuator. Activation is via a double-acting hydraulic actuator with spring, providing precise and reliable operation. The sealing class complies with DIN 60534-4 part 3 – Leakage Class V, ASME B16-104 – Class V, and ANSI FCI 70-2 – Class V.
As an optional feature, the valve can be supplied with a SIL III certified system according to IEC EN 61511, combined with MT 5356 control, enhancing operational reliability and system protection.