Reinforcement cage clamping tool and automatic seam welder

The invention relates to a reinforcement cage clamping tool. The reinforcement cage clamping tool comprises a mounting rod and a supporting assembly arranged on the mounting rod; the supporting assembly comprises a connecting sleeve arranged on the mounting rod, two sets of connecting pieces arranged on the connecting sleeve, lantern rings arranged on fixing rods, a supporting rod arranged on theconnecting sleeve, a first locking piece in threaded connection with the supporting rod and a sleeve arranged on the supporting rod; each set of connecting pieces comprises a plurality of fixing rods,the fixing rods in each set of connecting pieces are distributed in the circumferential direction of the connecting sleeve, one end of each fixing rod is connected with the connecting sleeve, the other end of each fixing rod is connected with two lantern rings, each lantern ring is connected to the corresponding fixing rod in each set of connecting pieces, and a gap exists between every two lantern rings; and one end of t