Patent attributes
A reservoir tank comprises a tank body and a double bottom. The tank body is constituted of a roof, a tank bottom plate and a tank wall. The roof and the tank bottom plate are fixed to the tank wall by welding. The double bottom includes a double bottom plate and a rim, which are fixed to each other by welding. A leakage liquid outlet is formed at one side of the double bottom plate on which reinforcement ribs are arranged in a lattice state. Cutouts are formed in the reinforcement ribs. The double bottom plate has a declivity so that the leakage liquid outlet is positioned at the lowermost level. The rim is provided with three detection ports. Upon welding the tank wall to the rim, the inside of the double bottom becomes an airtight state.
