苯乙烯装置活塞式压缩机填料密封环磨损机理及预防

Wear Mechanism and Prevention of Packing Seal Ring of Piston Compressor in Styrene Plant

分析了苯乙烯装置活塞式压缩机密封填料环的磨损机理,根据填料环实际磨损状况,对填料密封氮气压力进行优化调整与试验,并提出了全寿命周期的优化措施。填料环的磨损主要与介质压力Δp、填料环与活塞杆的摩擦系数μr、填料环与填料函之间的摩擦系数μ0相关。控制压缩机排气压力在1.8 MPa,较设计值降低0.5 MPa运行,延缓主密封环的磨损。采用分阶段调整密封氮气压力,使用新填料后,运行前期控制主密封氮气压力在0.08 MPa左右,较原设计值降低0.07 MPa,以延缓漏气/氮气环的磨损;运行后期,主密封环磨损增加,介质气泄漏量增加,将主密封氮气压力提高至0.15 MPa,以阻止介质气外漏。填料密封氮气压力优化调整后,延长了填料环的使用寿命,提高了活塞式压缩机运行的稳定性。

The wear mechanism of the packing ring for piston compressor in styrene plant is studied. According to actual wear condition of the packing ring, the nitrogen pressure of packing seal is optimized, adjusted and tested, and the optimization measures for its life cycle are put forward. The results show that the wear of the packing ring is mainly related to △p-the medium pressure,μr-the friction coefficient between the packing ring and the piston rod, and μ0-the friction coefficient between the packing ring and the stuffing box. By keeping compressor exhaust pressure at 1.8 MPa, 0.5 MPa lower than design value, the wear of the main seal ring can be delayed. By adjusting the sealing nitrogen pressure in stages, and keeping main sealing pressure of nitrogen in the early stage at about 0.08 MPa （0.07 MPa lower than design value） once new packing is added, the wear of leakage/nitrogen ring can be delayed. At the later stage, with the increasing wear of the main sealing ring and the increasing gas leakage, the main seal nitrogen pressure is lifted to 0.15 MPa to prevent gas leakage. After optimizing the nitrogen pressure adjustment of packing seal, the service life of the packing ring is prolonged, and the stability of the piston compressor operation is improved.