往复式压缩机工艺管线振动超标与治理

针对天然气长输管线常用的往复式压缩机工艺管线振动严重超标的问题,通过对不同工况下关键测点的振动测试和压力脉动分析,结合测点的测试数据和频谱特性,得出了压力脉动是导致管线振动主要原因的认识。为了控制压力脉动以消减激振力,根据现场的工艺要求,提出了增加汇气管的缓冲容积和改善管道配置的治理措施。完成整改后,再次进行了关键测点的振动测试和压力脉动分析,数据表明:整改前后压缩机在相同工况参数下运行时,测点最大振动位移由289.76μm降低到47.2μm;最大振动速度由34.26 mm/s降低到5.18 mm/s;压力脉动也符合API 618标准的要求。同时,管线的振动烈度满足多台压缩机同时运行的要求,使得增压站的天然气处理量至少由67.41×10~4m~3/d提升到119.52×10~4m~3/d。该案例表明,对压缩机进行变工况振动测试和频谱特性分析,可方便地找出主要振动源,为管道的减振治理提供依据。

Analysis and treatment of abnormal vibration of reciprocating compressor pipelines

Aiming at the actual situation of the abnormal vibration of reciprocating compressor pipelines, the vibration measurement and pressure pulsation analysis were conducted under different operating conditions. Analysis of the test data and spectrum characteristics showed that the major reason for abnormal pipeline vibration was excessive pressure pulsation. Combined with the site processing requirements, the vibration treatment measures to reduce vibration and control pressure pulsation were proposed by means of increasing the effective volume of gathering manifold and improving pipeline configuration. The vibration and pressure pulsation measurements were also conducted after pipeline remodeling. The test data indicated that the maximum vibration displacement was reduced to 47.2 μm from 289.76 μm, the maximum vibration velocity was reduced to 5.18 mm/s from 34.26 mm/s, and the pressure pulsation met the requirements of API 618 standard, under the same operating parameters of the compressor before and after remodeling. Meanwhile, the pipeline vibration severity met the condition that more than one compressor ran simultaneously, and thus the processing capacity was improved to at least 119.52×10⁴ m³/d from 67.41×10⁴ m³/d. This case study demonstrated that the key factors inducing excessive vibration can be easily found out through vibration measurement under different operating conditions and spectrum characteristics analysis. It also provides a reference for vibration elimination.