Iceland – Taps, cocks and valves – Preliminary Market Consultation for Steam Control Valves

Landsvirkjun would like to invite you to take part in our Preliminary Market Consultation for steam control valves that will be located in the T/G Unit valve room and form the HP separator pressure control and bypass arrangement, as indicated on P&ID drawing THT-P-LBK-T0-0515. Their primary function is to reduce the pressure of high-pressure steam that is not routed through the T/G Unit, from 27 bara to 9.3 bara, before the steam enters the existing medium-pressure system. The HP steam separator is designed for a maximum steam flow of 176 kg/s, which represents the maximum steam flow expected to be handled through the steam control valves. The T/G Unit is designed for flexible operation and variable load conditions, where the steam flow through the turbine may change depending on available steam, operating mode, start-up, shutdown, load changes and maintenance requirements. The steam control valves shall therefore be suitable for operation across a wide flow range and shall be capable of supporting stable pressure reduction from the HP steam system to the MP steam system during both partial bypass and full bypass operation. Special attention shall be given to the risk of H₂S-induced embrittlement and sulphide stress cracking, as well as the potential for SiO₂ scaling in high-temperature geothermal service. Vendors shall seek to minimize wear of valve components and noise emissions and shall avoid the use of plates or other components liable to clogging due to scaling.