5M class storage tank sealing circular seam inner supporting device

The embodiment of the invention discloses a 5M class storage tank sealing circular seam inner supporting device. The device is used for supporting the circle of a tank sealing circular seam of a storage tank and suitable for inner supporting in the large-diameter storage tank sealing circular seam welding process, low in weight and convenient to detach. The 5M class storage tank sealing circular seam inner supporting device comprises an inner supporting ring A, an outer supporting ring B and multiple supporting mechanisms C. Multiple single-hinge quickly-detaching mechanisms (6) are arranged on the periphery of the inner supporting ring A, the outer supporting ring B is of an annular structure composed of multiple outer ring peripheral supporting plates (4), and every two adjacent outer ring peripheral supporting plates (4) are peripherally connected through a multi-hinge quickly-detaching mechanism (3). One radial end of each multi-hinge quickly-detaching mechanism (3) is connected with one single-hinge quickly-detaching mechanism (6) through a radial connecting rod (5), and the other radial end is connected with one supporting mechanism C. The supporting mechanisms C are used for providing radial supporting force from inside to outside for the tank sealing circular seam.