Failure Analysis of a Cracked Gas Compressor

Cracked Gas Compressor (CGC) serves as the vital core of the Olefin plant. However, one of the leading companies in Indonesia, which employs CGC, faces the challenge of high vibration in both low-pressure (LP) and medium-pressure (MP) casings. This phenomenon is very important to overcome, because it may cause losses of thousands and even millions of dollars per day for the Company when there is a system failure. Vibration levels in MP casing have escalated from 13.8 $\mu \mathrm{m}$ to 39 $\mu \mathrm{m}$, and LP compressor vibration has abruptly risen to 52 $\mu \mathrm{m}$ from 12 $\mu \mathrm{m}$. Therefore, this study aimed to investigate the underlying causes of this high vibration in CGC. To analyze vibration issue, the Process Information (PI) and System1 software were employed. The result showed that the fouling of the rotor was the primary source of vibration in MP casing, while mechanical damage to rotating parts was responsible for vibration in LP casing. It is recommended to implementation of wash oil injection to reduce fouling and utilization of water injection to reduce compressor discharge temperature.