沥青泵波纹管密封失效分析与处理措施

Analysis of asphalt pump bellow seal failure and countermeasures

丙烷脱沥青装置沥青泵(双螺杆泵)金属波纹管密封在使用中频繁出现泄漏,分析密封摩擦副和波纹管结焦是造成泄漏的主要原因。生产工艺优化有效地解决了沥青携带丙烷造成沥青泵半抽空的难题,金属波纹管密封运行环境得到了很大的改善;密封集装式改造使螺杆泵维修劳动强度明显降低;安装蒸汽背冷使密封压盖处温度从210℃降低到了160℃,同时,背冷蒸汽有效减少了高温轴对轴承箱内啮合齿轮和轴承润滑油的传热,降低了轴承和齿轮的工作温度,延长了工作寿命,使金属波纹管密封得以长周期平稳运行。

The frequent leaking occurred in the operation of metal bellow seal in asphalt pump（double screw pump） in propane deasphalting unit,the analysis concluded that the seal wearing and coking on the bellow seal are the culprits of failure.The optimization of operation has effectively solved the problems of evacuation of asphalt pumps due to the propane carry-over in asphalt,operating environment of bellow seal has been greatly improved,and revamping of seal installation has reduced the work load of screw pump maintenance.The installation of back steam cooling has lowered the seal cover temperature to 160 ℃ from 210 ℃,and the back-pressure steam has effectively reduced the heat transfer from high-temperature shaft of meshing gear in the bearing box and bearing lube oil.As the result,the working temperature of the bearing and gear is reduced,the service life is extended and the long-term operation of metal bellow seal is ensured.