循环氢压缩机干气密封损坏的原因分析及应对措施  

Causes of Damage of Dry Gas Seal of Recycle-hydrogen Compressor and Countermeasures

作　　者：赵雷[1] 张立海[1] 

机构地区：[1]中国石化济南分公司,山东济南250101

出　　处：《中外能源》2010年第6期86-90,共5页Sino-Global Energy

摘　　要：济南分公司1.2Mt/a柴油加氢精制装置使用的循环氢压缩机为沈阳鼓风机厂生产的离心式压缩机,轴封采用约翰克兰28型中间带迷宫密封的螺旋槽串联式干气密封,密封控制系统分为一级密封控制流程、一级密封泄漏监测流程、二级密封和隔离气控制流程3个部分。2005年该系统因电器故障晃电造成联锁停机,分析认为事故状态下,一级主密封气瞬间中断,致使机体内部含液体及杂质的循环氢气体进入密封面,造成密封面气膜破坏是干气密封失效的主要原因,采取更换已损坏的干气密封、对润滑油泵电机增加3s延时自启、压缩机控制油压低联锁停机加3s延时、在过滤器后的密封气管线增设伴热和保温等措施后,干气密封运行状况良好。为适应主密封气的更换,对干气密封系统进行技术改造,改造思路是增上主密封气增压系统和气液聚结器,达到保证干气密封安全运行的目的。SINOPEC Jinan Company＇s 1.2Mt/a diesel hydrogenation unit uses a centrifugal compressor pro- duced by Shenyang Air Blower Plant as the recycle hydrogen compressor and its shaft seal is John Crane＇s Type 28 spiral-groove tandem dry gas seal with intermediate labyrinth.Its seal control system consists of a one-stage seal control process,a one-stage seal leak monitoring process and a two-stage seal and isolated gas control process.In 2005,the system experienced an interlock shutdown due to appliance voltage sag.After analysis ,technicians concluded that the main reason for the dry gas seal failure was that during the incident, the instant interruption of the primary sealing gas led to liquid-and foreign substance-containing circulating hydrogen in the machinery entering the sealing surface and damaging the gas film.They replaced the damaged dry gas seal,delayed the self-starting of the motor of the lubricating oil pump for three seconds,controlled the oil pressure of the compressor to delay the low interlock shutdown for three seconds and took heat trac- ing and insulation measures for the seal gas pipelines behind the filter.As a result of these measures,the dry gas seal worked very well.To support the replacement of the primary sealing gas ,these technicians conducted a technical upgrade on the dry gas seal system by adding a primary sealing gas pressurizing system and a liquid/gas coalescer to ensure the safe operation of dry gas seals.

关 键 词：干气密封 结构特点 工作原理 技术改造 

分 类 号：TH45[机械工程—机械制造及自动化]