The control of pipeline medium in nuclear power plant system of EPR unit is mainly carried out by motor valve regulating,in which the sealing form of motor valve and bonnet in related pressure loop of primary circuit is mainly welded at both ends of bellows to realize zero sealing of valve stem.Corrugated pipe is the only barrier to prevent valve leakage.If corrugated pipe is damaged,it will lead to medium leakage in the primary circuit,which will have a serious impact on the safe and stable operation of unit except for extremely high radioactivity.Therefore,the inspection of motor valve,especially the inspection of corrugated pipe structure,will be one of the key points and difficulties in maintenance.By designing and developing a special tool for off-line pressing of bellows,the sealing performance of validation bellows assembly is realized without destroying the structure of valve bellows assembly,and the stable operation of valve function is ensured.
关键词
核电站/核岛调节阀/销钉/改进
Key words
nuclear power plant/electric regulating valve/bellows/improvement
维普
万方数据