Control Valve Solutions for Thermal & Nuclear Power Plants
Application Description
Power generation is essentially a cyclic process of water and steam. Boiler feedwater is regulated by control valves and fed into the boiler, producing high-temperature, high-pressure steam that drives the turbine generator set. After expanding in the turbine, the steam is condensed into water in the condenser and returned to the cycle for reuse. Control valves are widely installed throughout the boiler, steam turbine and auxiliary systems; typical applications include the boiler feedwater valve, the feedwater pump minimum-flow recirculation valve, the high- and low-pressure bypass valves, heater drain valves and the deaerator level control valve.
Application Focus
1. Boiler feedwater valve: During boiler startup, the pressure differential can reach 100–300 kgf/cm² (approx. 9.8–29.4 MPa). Under normal operation, the differential pressure is lower while the flow rate is high. Therefore, the valve must be cavitation-resistant.
2. Feedwater pump minimum-flow recirculation valve: a critical valve for protecting the boiler feedwater pump, its working differential pressure reaches 160–350 kgf/cm² – the highest of any valve in the plant – so it must be both cavitation-resistant and anti-clogging.
3. Heater drain valve: the medium is saturated water, which is highly prone to flashing and causes erosion wear.
4. High- and low-pressure bypass valves: the medium is high-temperature, high-pressure steam; the valves must withstand thermal shock, reduce noise and respond quickly.
Solution Overview
1. Boiler feedwater valve: customized trim is used for the high-differential-pressure duty, meeting the requirements of both boiler start-up and normal operation; the start-up valve adopts a cavitation-resistant structure with Class V shutoff.
2. Feedwater pump minimum-flow recirculation valve: cavitation-resistant and anti-clogging design with Class V shutoff.
3. Heater drain valve: HTS-10/HCP-10 single-seat and cage-guided control valves are used for low-pressure heater drain service, while HKG-10 multi-stage pressure-reduction control valves serve normal and emergency drain duty on high-pressure heaters. The valves use materials specially selected to resist flashing erosion and are designed for Class V or Class VI shutoff. The cage adopts a multi-stage pressure-reduction structure with small-hole throttling, providing up to five stages of pressure reduction and effective noise attenuation. Maximum rating ANSI 600, maximum size DN500, with noise limited to 85 dB(A).
4. High- and low-pressure bypass valves: multi-stage pressure-reduction trim provides thermal shock resistance and noise attenuation.
Customer Value
Designed for high differential pressure and severe cavitation in thermal and nuclear power plants, this solution covers the core valve groups: boiler feedwater valves, feedwater pump minimum-flow recirculation valves, heater drain valves, and high- and low-pressure bypass valves. Using proprietary multi-stage trim technologies for pressure reduction, cavitation resistance, and anti-flashing, it addresses high-differential-pressure cavitation, media erosion, thermal shock, high noise, and media clogging, and adapts to unit start-up/shutdown and dynamic load-following.
The valves deliver stable, reliable performance, reducing equipment failures, downtime losses, and O&M costs, while the multi-stage noise-reduction design lowers on-site noise. The solution ensures safe, continuous operation of the plant's thermal system, improves unit efficiency, supports a stable power supply, and helps energy facilities achieve safe, efficient, and green operation.
Related Products
Single-Seat Control Valve: HTS Series
Multi-Stage Pressure-Reduction Control Valve: HKG-1 Series
Pilot-Operated Control Valve: HCP/HKG-5 Series
Control Ball Valve: ZJHR Series
