高温油泵串级波纹管密封改造

近年来,石化行业高温油泵泄漏着火事故主要原因就是密封泄漏.分析了某炼油厂炼油装置高温油泵单端面波纹管密封泄漏的原因,包括密封面磨损、波纹管失弹、密封面热裂等.根据对单端面密封使用效果及隐患的分析,对高温油泵进行改造,包括机械密封的冲洗方案由PLAN32＋ 62改为PLAN32＋ 53B和将单端面波纹管机械密封改为串级双端面波纹管机械密封.详细介绍了改造的结构特点和技术优势,冲洗方案的改造极大地改善了密封的工作环境,使密封的使用寿命显著延长;串级波纹管机械密封的改造为油泵增加了一道防泄漏措施,并能够提前预判密封可能存在的故障,保证了密封的安全可靠运行.现场使用效果表明：高温油泵波纹管串联式机械密封使用寿命长、安全可靠、密封冷却效果好.

Revamp of high-temperature oil pump cascade bellows seal

In recent years, high-temperature pump leakage fire accidents have occurred in petrochemical industry, and the main cause of these accidents is the seal leakage. The causes of the seal leakage of high- temperature pump＇ s single bellow seal are analyzed, mainly including the sealing surface wear, bellows miss and sealing surface cracking, etc. Based upon the application results and analysis of potential hazard of refin- ery single seal, the high-temperature pumps are revamped, the flushing of mechanical seal is revamped to PLAN32 ＋ 53B from PLAN32 ＋ 62 and single bellow mechanical seal is changed to cascade double bellow me- chanical seal. The revamped structural characteristics and technical advantages are described in detail. The revamping of flushing process has greatly improved the working conditions of seals and greatly extended the service life. In addition, the revamping of cascade bellow mechanical seal has provided an additional leak pre- vent measure for oil pumps. The possible potential accidents of seal can be predicted and safe operation of the mechanical seal can be ensured. The field application shows that the cascade double bellow mechanical seal for high-temperature oil pumps is long in service life, safe in operation and good in cooling performance.