碱泵机械密封失效分析及改进

由于工艺介质的改变,脱硫联合装置碱液泵(原介质为水)机械密封频繁失效,使用周期为20天左右。对密封结构和工艺介质特性进行失效分析后发现,弹簧内置密封结构不适合在此工艺介质中长期运行。通过对密封结构的设计改进和密封系统的改造,提高了密封的使用寿命和装置的安全可看性。建议当工艺条件或密封介质发生改变时,应及时与设计单位沟通,预防机械密封过早的失效,继而影响工艺装置的正常运行。

Alkali pump mechanical seal failure analysis and improvement

Mechanical seal used in lye pump for desulphurization equipment occurs frequent failure because of the change of process medium, and the life cycle of this mechanical seal is about 20 days. After failure analysing of seal structure and process medium, we found that spring built-in seal structure is not fit to work in this process medium for long time running. The seal＇s service life and device＇s safe reliability is increased by design improvement of seal structure and seal system. We suggest that customer should communicate with design institute as soon as possible when process conditions or sealing medium changes, in order to avoid affecting normal running of process device because of early failure of mechanical seal.