Traceability analysis was carried out on the equipment damage caused by the unreasonable structure and the unsuitable sealing form of the filter with electric scraping brush in the quench oil system of ethylene plant. Through the in-depth analysis of the problems occurred in the past, a technical transformation plan was proposed combined with the mechanical principle, and the plan was implemented and verified. The problems in this type of filter such as damaged electric scraping brush and frequent leakage of mechanical seal were successfully solved, providing guarantee for the long-term, safe and stable operation of the ethylene plant.