High-inlet three-way valve and high-plus-outlet three-way valve (or gate valve) were installed in the high-pressure heater inlet and outlet, two kinds of valves supporting the use. Under normal working conditions, through the DCS control, three-way valve bypass closed, the main road open, water supply through the main road into the high-pressure heater, high-pressure heater preheated into the boiler.

 When the high heater failure, by the DCS control actuator (hydraulic cylinder or electric equipment) action, three-way valve main road closed, bypass open, so that high-pressure heater out of the maintenance, water supply through the bypass directly into the boiler. Through the high three-way valve to ensure that the normal operation of the boiler under the conditions of high-pressure heater can be easily carried out to lift and put into use, improve the efficiency of the use of thermal Power units.


  • Nominal diameterDN175-DN550, NPS 5-NPS 22
  • Pressure classPN200-PN450, Class 1500-Class 3500
  • Implementation of the standardNB / T 47044, ASME B 16.34