螺纹锁紧环换热器内漏原因分析及对策

Analysis for internal leakage of threaded ring heat exchanger and countermeasure

针对某焦化汽油和柴油加氢装置螺纹锁紧环换热器在运行过程中出现的内漏问题,对换热器结构和相关操作参数进行分析,判断造成换热器E101A发生内漏的主要原因为E101A壳程入口温度由185℃下降至165℃,由于换热温度降低导致壳程密封垫片回弹能力不足,密封比压不够而多次发生泄漏。对换热器进行在线紧固仍不能解决换热器内漏问题,后通过工艺调整提高E101A管程、壳程入口温度,经过长期运行表明,E101A未再发生内漏,有效解决了E101A由于换热温度降低而导致内漏的问题。

The construction of the heat exchanger and related operating parameters are analyzed to find out the causes of the internal leakage of the thread locking ring heat exchanger E101A in the coker gasoline and diesel hydrotreating units. The main cause of the internal leakage is that the inlet temperature of E101A shell side goes down from 185 ℃ to 165 ℃. As the heat exchange temperature of E101A is further reduced,both the resilience of seal gasket and the sealing pressure are insufficient for the shell side,which causes the internal leakage of the heat exchanger. On-line tightening can not solve the internal leakage problem of heat exchanger,but it is finally solved by raising the E101A＇s inlet and outlet temperatures. The long-term operation shows that there is no internal leakage of heat exchanger E101A and the internal leakage problem of E101A due to reduction of heat exchange temperature has been effectively solved.