超低温介质泵用机械密封模拟试验研究  

Simulation Test Research on Mechanical Seals for Ultra-low Temperature Medium Pumps

作　　者：刘杰 李香 郑国运 李凤成 丁思云 谢星 LIU Jie;LI Xiang;ZHENG Guo-yun;LI Feng-cheng;DING Si-yun;XIE Xing(Machinery Industry Mechanical Seals Engineering Research Center,Hefei General Machinery Research Institute Co.,Ltd.,Hefei 230031,China;General Machinery and Key Basic Component Innovation Center(Anhui)Co.,Ltd.,Hefei 230031,China;Sinomach General Machinery Science&Technology Co.,Ltd.,Hefei 230031,China)

机构地区：[1]合肥通用机械研究院有限公司机械工业机械密封工程技术研究中心,安徽合肥230031 [2]通用机械关键核心基础件创新中心(安徽)有限公司,安徽合肥230031 [3]国机通用机械科技股份有限公司,安徽合肥230031

出　　处：《液压气动与密封》2024年第12期27-31,共5页Hydraulics Pneumatics & Seals

基　　金：安徽省重点研发计划(2022a05020002)。

摘　　要：以某空分装置超低温液氧泵用机械密封为研究对象,建立了超低温机械密封模拟试验系统,以液氮为试验介质开展模拟试验,研究了吹扫氮气温度和声发射信号的变化规律,在密封启停过程中,密封端面间存在固体撞击,稳定运转过程中无固体撞击,密封端面间处于非接触运转。在启动过程中,超低温机械密封摩擦副间流体动压效应不足以形成完整的润滑膜,存在微凸体接触,声发射信号迅速增大并出现峰值,随着转速的升高密封端面流体动压效应增强,声发射信号逐渐降低,直至密封运行稳定,声发射信号趋于稳定。在停机过程中,随着转速的降低,因流体膜剪切效应降低,声发射信号先出现小幅下降,后因转速继续降低,流体动压效应不足以形成完整的流体膜,声发射信号迅速增大并出现峰值。整个试验过程中吹扫氮气温度在10.7~22.5℃之间,密封设计合理,满足设备现场使用要求。Taking the mechanical seal used in the ultra-low temperature liquid oxygen pump of a certain air separation unit as the research object,a simulation test system for ultra-low temperature mechanical seal was established.The simulation test was carried out using liquid nitrogen as the test medium,and the variation law of blowing nitrogen temperature and acoustic emission signal was studied.During the sealing start stop process,there was solid impact between the sealing end faces,and there was no solid impact during stable operation.The sealing end faces were in non-contact operation.During the start-up process,the fluid dynamic pressure effect between the sealing end faces is insufficient to form a complete fluid film,and there is micro convex contact.The acoustic emission signal rapidly increases and peaks appear.As the speed increases,the fluid dynamic pressure effect on the sealing end faces increases,and the acoustic emission signal gradually decreases until the sealing operation stabilizes and the acoustic emission signal tends to stabilize.During the shutdown process,as the rotational speed decreases,the shear effect of the fluid film decreases,and the acoustic emission signal first shows a slight decrease.Later,as the rotational speed continues to decrease,the fluid dynamic pressure effect is insufficient to form a complete fluid film,and the acoustic emission signal rapidly increases and peaks.The temperature of the nitrogen gas blown during the entire experiment was between 10.7℃and 22.5℃,and the sealing design was reasonable,meeting the requirements for on-site use of the equipment.

关 键 词：超低温液氧泵 机械密封 试验研究 声发射 

分 类 号：TB42[一般工业技术]