秦山第二核电厂1&2号机组主蒸汽安全阀改进分析

秦山第二核电厂12号机组拟将其加能助动式主蒸汽安全阀改为弹簧加载式安全阀。通过比对秦山第二核电厂34号机组主蒸汽安全阀设计,提出了12号机组主蒸汽安全阀改进方案,即第1组阀门采用弹簧加载式并调整开启整定值,并从机械设计、仪控设计和安全分析等方面论证了该方案的可行性。新的改进方案在保证安全的前提下,简化了设计,大幅减少了工程投入,同时降低了系统和控制逻辑复杂化后带来的潜在停堆风险的增加。

Analysis of Main Steam Safety Valve Improvement for Qinshan Nuclear Power Plant Phase 2 Unit 1&2

An improvement for Qinshan Nuclear Power Plant Phase 2 unit 1&2, in which the power-operated valves are replaced with the spring-loaded valve with setpoint adjustment for the 1st group safety valves of steam generators, would be adpoted on the basis of comparison with similar improvement implemented in Qinshan Nuclear Power Plant Phase 2 unit 3&4. The feasibility was evaluated from several aspects, including mechanical design, instrument & control design and safety analysis. On the premise of guaranteeing safety, this improvement can simplify design, observably reduce project costs and avoid increasing the potential probability of the reactor trip risk induced by complication of the system and control logic.