Short-circuit Transition Welding System Based On Push-pull Wire Feeder

In recent years, the lightweight metals have been used more and more widely inthe automotive industry, shipbuilding, container industry, sheet metal welding has alsobecame an important issue for people to solve. The heat input is higher of traditionalarc welding method, unable to satisfy the needs of the welding plate, and the practiceproves Push-and-Pull wire short-circuit transition welding technology can effectivelysolve the problem, for the traditional arc welding method, the short-circuit transitionis by high-current generation electromagnetic contractile force to complete droplettransition, while Push-and-Pull wire short-circuit transition withdrawing the wiredroplet transfer, droplet transfer by mechanical force, this method can not only reduceheat input, and can effectively reduce the splash of the welding process.Push-and-Pull wire short-circuit transition through real-time acquisition of the outputcurrent and voltage signals to judge welding state is in a short circuit or burning arcstage, and control the wire to feed or Withdrawing.In order to realize the transition of the Push-and-Pull wire short-circuit lowenergy welding, this topic designed a welding system based on push-pull wire andanalysis the principle of work:This system mainly include the welding power, wiresystem and control coordinate parts.The welding power select the current mode PWMchip of uc3846to be controller the core, using current-mode PWM control technologyto achieve the pulse width modulation; Wire systems use rotation inertia small, fastresponse of the ac servo motor, will be able to realize the high frequency the push andpull of the wire, is the key of realize push-pull wire function; TMS320F2808DSP ascontrol core of coordinated control part, for achieving coordination work of thewelding power source and wire feed system, short circuit transfer withdrawing thewire, and sent to the wire in the state of the arc, eventually meet the requirements ofthe low heat input welding.Analyzes the factors of Push-and-Pull wire short-circuit, the influence factors ofthe stability include the motor speed, welding speed, stick-out and other and the topicexplored how to select the base value current, short-circuit current and ignites current,realized the parameters optimization and the stability welding of the Push-and-Pullwire short-circuit transition.