A welding apparatus for welding workpieces by means of a welding arc which is ignited between a non-consumable welding electrode and the workpieces and produces a molten pool, wherein the welding is performed in a welding process including a plurality of welding cycles, the parameters of which can be set via an interface of the welding apparatus. Each welding cycle of the welding process has a high-current welding phase, during which a high welding current flows, and a low-current welding phase, during which a low welding current flows. In the high-current welding phase and/or in the low-current welding phase of, with the relevant welding cycle being set accordingly, current pulses can be applied, and at the beginning of the high-current welding phase, with the relevant welding cycle being set accordingly, high-frequency ignition pulses can be applied for the contactless ignition of the welding arc.

A MIG welding method for carbon steels using an Ar shielding gas. The method includes short-circuiting a welding wire and a base material. The average short-circuiting frequency in welding is 20 Hz to 300 Hz and the maximum short-circuiting period is 1.5 s or less.

An arc welding system providing improved molten metal droplet transfer. The system includes a welding power source having a welding power supply, a welding waveform generator, and a controller. Two fluxed cored welding wire electrodes are connected to the power source and are powered by the same welding output voltage and current produced by the power source. A feedback circuit is connected to the power source to provide an adaptive response to maintain an average welding output voltage. The controller controls the waveform generator and the power supply to superimpose welding current pulses onto a welding waveform of a CV flux cored arc welding process, that uses CO.sub.2 as a shielding gas, to generate a modified waveform of a modified CV flux cored arc welding process. The current pulses are superimposed in time to form molten metal droplets between ends of the two electrodes during the modified welding process.

A pulsed welding regime includes a peak phase in which energy is added to an electrode and a weld puddle, and a molten ball begins to detach from the electrode, followed by a dabbing phase in which current is significantly reduced to place the ball in the weld puddle with addition of little or no energy. The resulting short circuit clears and the system proceeds to a background phase. The current in the dabbing phase is lower than the current during the background phase. The process may be specifically adapted for particular welding wires, and may be particularly well suited for use with cored wires. The dabbing phase allows for lower energy to be transferred to the sheath of such wires, and resets the arc length after each pulse cycle.

In controlling an arc welding of consumable electrode type in which pulse welding and short-circuit welding alternately repeat, forward feeding and backward feeding of a welding electrode periodically repeat in a short-circuit welding period. The forward feeding of the welding electrode starts when a welding current is smaller than a base current immediately before a pulse period ends.

A three stage power source for an electric arc welding process comprising an input stage having an AC input and a first DC output signal; a second stage in the form of an unregulated DC to DC converter having an input connected to the first DC output signal and converts the first DC output signal to a second DC output signal of the second stage; and a third stage to convert the second DC output signal to a welding output for welding wherein the input stage and the second stage are assembled into a first module within a first housing structure and the third stage is assembled into a second module having a separate housing structure connectable to the first module with long power cables. The second module also includes wire feeding systems and electronics.

In order to develop a welding process in such a way that uniform flaking of a weld seam can be guaranteed even with a higher number of short-circuit cycles, a specific number of short-circuit cycles is specified for the cold welding phase and the cold phase duration of the cold welding phase is determined for a number of short-circuit cycles that exceeds a specified limit cycle number, depending on a determined cold phase time and after the cold welding phase, there is a switch to the hot welding phase.

There is provided an arc welding control method for performing a forward/reverse feeding control of alternating a feeding rate of a welding wire between a forward feeding period and a reverse feeding period, and generating short-circuiting periods and arc periods to perform welding. The welding wire is fed forwardly upon starting the welding. The forward feeding is continued during a transient welding period from a time point at which the welding wire comes in contact with a base material and conduction of welding current is started to a time point at which convergence on a steady welding period is performed. The transient welding period is terminated at the short-circuiting period. The forward/reverse feeding control is started from the reverse feeding period after the termination of the transient welding period.

A consumable electrode arc welding method using a shielding gas containing argon comprises: setting a first welding condition in which a first welding current is supplied to a welding wire; and setting a second welding condition in which a second welding current is supplied to a welding wire. The first welding condition and the second welding condition are welding conditions in which a reference current of the welding current is 350 A or higher and a current variation range is from 50 A to 150 A, and the first welding condition and the second welding condition are switched at a cycle of a frequency ranging from 1 Hz to 5 Hz.

A welding system includes a power source configured to generate power and deliver the power to a welding torch. The power is provided in accordance with an electrode negative pulse welding regime that includes a cyclic peak, followed by a stabilization phase, then a return to a background level. The stabilization phase has a generally parabolic current shape, and is performed in a current-closed loop manner until a transition point. Resulting weld performance is improved, with a globular-like transfer mode, reduced shorts and enhanced arc stability.