The invention discloses an outer floating roof
storage tank with
lightning rods and a
metal roof. The outer floating roof
storage tank comprises a tank body, a floating roof, the
metal roof and the
lightning rods, the
metal roof is erected outside the floating roof, a supporting column and tank roof angle steel are welded, and the supporting column and the tank body are reliably and electrically connected; the plurality of
lightning rods are arranged above the
metal roof,
lightning rod supporting rods are fixed on a fixing supporting part which is pre-installed and is located on a metal plate,the lightning rods are made of hot-dip galvanized round steel or steel pipes, moreover, the sectional area of each
lightning rod is not smaller than 176mm<2>, the length of each
lightning rod is 2m,the
diameter of each lightning rod is not smaller than 16 mm, the lightning end of each lightning rod is in a hemispherical shape, and the bending
radius of each lightning end ranges from 4.8mm to 12.7mm. The protection range of the lightning rods is calculated through a rolling ball method, the number and the positions of the lightning rods are determined, the lightning rods are arranged above the
metal roof and are in reliable
electrical connection with the metal plate, so that direct lightning protection is achieved on the
metal roof, the metal roof of the outer floating roof
storage tank is prevented from being directly hit by the
thunder and lightning, through the metal roof, the influence exerted by natural factors such as rainwater and sunshine on internal accessories can be reduced, moreover, the damage caused by
thunder and lightning induction on the interior of the storage tank can also be effectively avoided, so that multiple lightning protection on the outer floating roof storage tank is realized, and the occurrence frequency of fire accidents caused by lightning on the storage tank is greatly reduced.