To stabilize a growth state of a droplet during an electrode negative polarity peak period in consumable electrode AC pulse arc welding. In an AC pulse arc welding control method for controlling welding which is performed by feeding a welding wire, and applying an electrode negative polarity base current during an electrode negative polarity base period, then applying an electrode negative polarity peak current during an electrode negative polarity peak period, and then applying an electrode positive polarity current during an electrode positive polarity period, to repeatedly apply these welding currents, the electrode negative polarity peak period includes a rising period Tu, a peak period Ta, and a falling period Td, a time ratio of the peak period Ta to the electrode negative polarity peak period is less than 20%, and the falling period Td is a period twice or more longer than the rising period Tu.

The purpose of the present invention is to reduce the amount of sputtering in a welding method wherein a welding wire feed rate is alternately switched between a forward feed period and a reverse feed period. Provided is an arc welding control method that switches a feed rate Fw for welding wire alternately between a forward feed period and a reverse feed period, repeats a short period and an arc period, and electrifies with a welding current Iw switched to a small current value in the latter half of the arc period, wherein a basic voltage setting value is set according to an average feed rate setting value, the error amplitude value for a voltage setting value and the basic voltage setting value is calculated, and the timing (current reduction time Td) for switching the welding current Iw to the small current value is varied on the basis of the average feed rate setting value and the error amplitude value.

The purpose of the present invention is to reduce the amount of sputtering in a welding method wherein a welding wire feed rate is alternately switched between a forward feed period and a reverse feed period. Provided is an arc welding control method that switches a feed rate Fw for welding wire alternately between a forward feed period and a reverse feed period, repeats a short period and an arc period, and electrifies with a welding current Iw switched to a small current value in the latter half of the arc period, wherein a basic voltage setting value is set according to an average feed rate setting value, the error amplitude value for a voltage setting value and the basic voltage setting value is calculated, and the timing (current reduction time Td) for switching the welding current Iw to the small current value is varied on the basis of the average feed rate setting value and the error amplitude value.

A welding or additive manufacturing contact tip includes an electrically-conductive body extending from a proximal end of the body to a distal end of the body. The body forms a first bore terminating at a first exit orifice at a distal end face of the body, and a second bore terminating at a second exit orifice at the distal end face of the body. The first and second exit orifices are separated from each other by a distance configured to facilitate formation of a bridge droplet between a first wire electrode delivered through the first bore and a second wire electrode delivered through the second bore during a deposition operation.

A pressure welding method and a pressure welding device (1) are provided. The pressure welding device (1) includes a plastification device (7), an upsetting device (8) and component mountings (34,35,36,37) for the components (2,3,3,4) to be welded together and a machine frame (12). The pressure welding device (1) further includes a plurality of machine heads (13,14), each having a component mount (34,35), which machine heads are movably arranged on the machine frame and are connected to respective upsetting drives (22). The machine heads (13,14) and respective upsetting drives (22) can be independently driven. An upsetting head or support head (27), which is preferably secured on the frame, is arranged between the machine heads (13,14).

In control applying a gradient to a command voltage value during an arc period, although stable welding can be performed even in a case where a protrusion length of a welding wire becomes long, when the disturbance such as sudden change in the protrusion length is generated, a current waveform of the arc period is undershot, the short circuit period is disturbed, and it took time to return to the stable state, and the amount of sputter generation is also increased. Therefore, it is possible to suppress a change in current such as undershoot or the like when the disturbance is generated, stabilize short circuit cycle, perform welding with a strong resistance to disturbance and a small amount of sputter generation by changing an inductance value a plurality of times during the arc period.

In control applying a gradient to a command voltage value during an arc period, although stable welding can be performed even in a case where a protrusion length of a welding wire becomes long, when the disturbance such as sudden change in the protrusion length is generated, a current waveform of the arc period is undershot, the short circuit period is disturbed, and it took time to return to the stable state, and the amount of sputter generation is also increased. Therefore, it is possible to suppress a change in current such as undershoot or the like when the disturbance is generated, stabilize short circuit cycle, perform welding with a strong resistance to disturbance and a small amount of sputter generation by changing an inductance value a plurality of times during the arc period.

Disclosed is a method for controlling arc welding where an arc is generated between a welding wire as a consumable electrode and an object to be welded. The method includes: keeping a wire feed speed at a predetermined constant speed in a steady-state welding period; and at a time point when welding termination is ordered, either switching the wire feed speed from the predetermined constant speed to a wire feed speed at which the welding wire is fed in alternating forward and backward directions, or decreasing the wire feed speed from the predetermined constant speed with time, and then switching the wire feed speed to the wire feed speed at which the welding wire is fed in alternating forward and backward directions at a time point when a predetermined time period has passed since when welding termination was ordered.

A system and method to make a welder aware of contact tip-to-work distance (CTWD) during a welding process. One or both of welding output current and wire feed speed is sampled in real time during the welding process. The actual CTWD is determined in real time based on at least one or both of the sampled welding output current and wire feed speed. The actual CTWD may be compared to a target CTWD in real time, where the target CTWD represents an estimated or desired CTWD for the welding process. A deviation parameter may be generated based on the comparing. An indication of the deviation parameter or the actual CTWD may be provided to a welder performing the welding process as feedback, allowing the welder to adjust the actual CTWD to better match the target CTWD in real time during the welding process.

A welding or additive manufacturing contact tip includes an electrically-conductive body extending from a proximal end of the body to a distal end of the body. The body forms a first bore terminating at a first exit orifice at a distal end face of the body, and a second bore terminating at a second exit orifice at the distal end face of the body. The first and second exit orifices are separated from each other by a distance configured to facilitate formation of a bridge droplet between a first wire electrode delivered through the first bore and a second wire electrode delivered through the second bore during a deposition operation.