The utility model relates to a sealed circular connector conversion equipment, including adapter and fuel tank shell, the adapter has casing and tray, be equipped with four welding needle in the casing of adapter, four welding needle is in evenly distributed in the casing of adapter, there are a plurality of flat head screw holes on the tray of adapter, the adapter passes through flat head screw to be fixed fuel tank shell is last, the below of adapter is equipped with the circle of nai the oil seal, the fuel tank shell internal fixation is stretched into to the below of adapter, uses the glue of nai the oil seal to flood the below of adapter makes one end of welding needle is exposed with the bonding wire. Compare with prior art, the utility model has the advantages of simple effective, guaranteed to have accomplished under the condition of leakproofness in the oil tank with the outer wiring conversion of oil tank, use safe and reliable.