Abstract:The importance of the SO2 fan in the smelting gas acid production system, the basic principle of its lubrication system are introduced. During operation, the auxiliary oil pump cannot automatically stop after the SO2 fan is normally turned on. The fault is analyzed, the first-stage pressure control valve is modified, and the processing gasket is installed on the top of the valve spring. When the oil pressure of the lubrication pipeline reaches 0.8MPa, the valve opens automatically. After the modification the problem that the auxiliary oil pump cannot be shut down was effectively solved, the stability of the SO2 fan lubrication system was improved, and the service life of the equipment was extended.