Abstract: A machine for automatically applying one or more bonding or sealing seams to the peripheral surface of a tank or vessel having a non-cylindrical cross section. More specifically the machine provides means for supporting and axially rotating a generally rectangular vessel having planar walls and connecting arcuate corners so that all of the peripheral surfaces of the vessel move under the sealing or bonding means at a constant rate of speed and at a fixed distance therefrom. The same is achieved by the use of gripper assemblies having a configuration corresponding to that of the vessel. Each gripper assembly includes a sprocket chain which corresponds to the configuration of the vessel. A sprocket wheel engages each chain to rotate the gripper assemblies and the vessel retained therebetween.