Abstract: In this paper, the structural defects of the dilated-oil-bleeder, the tank-front equipment installed in dome roof tank and the floating roof tank, is analyzed. The improvement measures are put forward, including installing ari arc-fender at the end of the bleeding pipeline and the distance between the fender and the tank wall must be less than 25 mm to prevent the oil dropping from producting static electricity; a thick wall' thermometer tube is welded with the tank wall and then connected with a piece of flange; the globe valve and check value are connected with the flange; the "∩"-shape structure of the dilated-oil-bleeder in the floating roof tank is improved. With these measures, the oil stored within the tank is effectively prevented from escaping.