Pentair Valves & Controls secured a contract to supply more than 200 high-pressure electric-operated gate and check valves to the Tianwan nuclear power plant in Jiangsu province, China. The Sempell safety relief and isolation valves for conventional and nuclear power applications are engineered and manufactured at its specialist facility in Germany. They will be installed in the main steam and emergency core cooling systems in two new Gen lll VVER1000/428 Pressurised Water Reactors (PWR) for Tianwan Units 3 and 4, and are scheduled for installation by 2016.
Pentair success in securing the project was primarily due to its experience and installed base within VVER-type PWR installations. Its qualified wedge gate valve design with Cobalt-free hard facings is engineered to eliminate the potential for thermal binding. Working closely with plant operator Jiangsu Nuclear Power Co. and plant engineering and procurement contractor (EPC) Atomstroyexport, Pentair demonstrated its Sempell split-wedge valve design as part of the design process to overcome the risk of thermal binding.
Qualification of the valve design was undertaken on an original gate valve through tests that mimic the extreme requirements caused by pipe rupture. Tests were undertaken at Pentair’s research laboratory at its facility in Germany with water and steam without mass flow, followed by three pipe rupture tests using steam on the full-scale valve test rig ‘GAP’.