The article considers dynamic modeling and design features of a universal rotary welding device adapted to the needs of modern production. A modular construction principle is described, which allows to increase the functional flexibility and maintainability of the system. Based on the Lagrangian approach, the equations of motion for the rotary and tilting components of the mechanism are formulated, taking into account the action of external loads, damping forces and moments of inertia. Control options are analyzed, in particular the use of PID and adaptive controllers, which allow to ensure high positioning accuracy and reduce vibrations during operation.