Methods and apparatus to synergically control a welding-type output during a welding-type operation are disclosed. An example welding-type power supply includes a power conversion circuit configured to convert input power to welding-type power and to output the welding-type power to a welding-type torch; a communication circuit configured to receive a control signal from a remote control device during a welding-type operation; and a control circuit configured to synergically control a voltage of the welding-type power and a wire feed speed based on the control signal.

A welding or additive manufacturing power supply includes output circuitry configured to generate a welding waveform, a current sensor for measuring a welding current generated by the output circuitry, a voltage sensor for measuring an output voltage of the welding waveform, and a controller operatively connected to the output circuitry to control the welding waveform, and operatively connected to the current sensor and the voltage sensor to monitor the welding current and the output voltage. A portion of welding waveform includes a controlled change in current from a first level to a second level different from the first level. The controller is configured to determine a circuit inductance from the output voltage and the controlled change in current, and further determine a change in resistance of a consumable electrode in real time based on the circuit inductance.

The present invention relates to methods and apparatus for detection of fire states in the presence of welding activities. In some examples, the welding detection system may algorithmically calculate a risk of a fire state developing. In some embodiments, the welding fire detection and prevention system may communicate warning states to users, supervisors, equipment and/or building monitoring systems.

The invention relates to a method for the dynamic feeding of shielding gas, comprising feeding a shielding gas to a component in a welding operation, sending the temperature of a region of the component; and setting a composition of the shielding gas according to the sensed temperature.

One embodiment of the present invention relates to a welded member obtained by overlapping portions of two sheets of base metal and performing fillet welding thereon using weld material, and provides a welded member having excellent fatigue strength of welded portion, and a method for manufacturing same, the welded member comprising base metal, a weld bead and root-reinforcing weld metal, wherein the base metal has a tensile strength of 780 MPa, the weld bead has a toe angle of 160 degrees or greater and the weld bead and the root-reinforcing weld metal have a Vicker's hardness of 280-320 Hv and a fatigue strength of 350 MPa or higher.

A welding system includes a consumable electrode, torch, wire feeder, and power supply. The power supply is configured to provide a plurality of waveforms to the torch to generate a welding current in the electrode. Each of the plurality of waveforms includes a pinch current portion followed by an arcing current portion, and the pinch current portion is preceded by a first arc suppression portion and the arcing current portion is followed by a second arc suppression portion. An arc exists between the electrode and a workpiece during the arcing current portion, and an air gap without an arc exists between the consumable electrode and the workpiece during the arc suppression portions. The power supply is configured to detect a short between the electrode and workpiece and generate the pinch current portion when the short is detected, and the wire feeder stops feeding the electrode when the short is detected and restarts feeding the electrode after the short is clear.

Provided are an arc welded joint and an arc welding method. The arc welded joint has a slag-coverage area ratio S.sub.RATIO (%) of 15% or less, and a weld bead width ratio W.sub.RATIO (%) of 60% or more. The S.sub.RATIO is calculated by using an equation S.sub.RATIO=100×S.sub.SLAG/S.sub.BEAD. In this equation, an area of a surface of a weld bead formed by performing arc welding on a steel sheet is defined as a weld bead surface area S.sub.BEAD (mm.sup.2) and, of the weld bead surface area S.sub.BEAD, an area of a region covered with slag is defined as a slag surface area S.sub.SLAG (mm.sup.2). The W.sub.RATIO is calculated by using an equation W.sub.RATIO=100×W.sub.MIN/W.sub.MAX from a maximum value W.sub.MAX (mm) and a minimum value W.sub.MIN (mm) of a weld bead width in a direction perpendicular to a welding line of the weld bead.

Provided are an arc welded joint and an arc welding method. The arc welded joint has a slag-coverage area ratio S.sub.RATIO (%) of 15% or less, and a weld bead width ratio W.sub.RATIO (%) of 60% or more. The S.sub.RATIO is calculated by using an equation S.sub.RATIO=100×S.sub.SLAG/S.sub.BEAD. In this equation, an area of a surface of a weld bead formed by performing arc welding on a steel sheet is defined as a weld bead surface area S.sub.BEAD (mm.sup.2) and, of the weld bead surface area S.sub.BEAD, an area of a region covered with slag is defined as a slag surface area S.sub.SLAG (mm.sup.2). The W.sub.RATIO is calculated by using an equation W.sub.RATIO=100×W.sub.MIN/W.sub.MAX from a maximum value W.sub.MAX (mm) and a minimum value W.sub.MIN (mm) of a weld bead width in a direction perpendicular to a welding line of the weld bead.

Systems, methods, and apparatus to preheat weld wire are disclosed. An example contact tip includes: an inner bore configured to conduct current to a consumable welding electrode; screw threads on an exterior of the contact tip; and a head opposite the screw threads on an exterior of the contact tip to enable threading and dethreading of the contact tip.

Systems, methods, and apparatus to preheat weld wire are disclosed. An example contact tip includes: an inner bore configured to conduct current to a consumable welding electrode; screw threads on an exterior of the contact tip; and a head opposite the screw threads on an exterior of the contact tip to enable threading and dethreading of the contact tip.