According to one embodiment, a welding apparatus includes a first welding machine including a first torch member formed of a metallic material to weld a first weld zone of a weld object, a second welding machine including a second torch member formed of a metallic material to weld a second weld zone of the weld object, a first sensor installed on the first torch member to detect an elastic wave transmitted to the first torch member, a second sensor installed on the second torch member to detect an elastic wave transmitted to the second torch member, and first and second processing circuits determining a welding condition of the first weld zone and the second weld zone based on a detection signal from the first sensor and the second sensor.

A fusion welding device includes: a robot arm; a fusion welding hand attached to the robot arm and including a fusion welding head for fusing and joining together workpieces while being separated from the workpieces; a support provided to the fusion welding hand and abutting on the workpieces; a force sensor for detecting a force and a moment exerted, through the support, by the workpieces; and a control section configured to control motion of the robot arm in accordance with parameters calculated from a signal outputted from the force sensor.

A teaching tip is removably attached to a distal end portion of a power feeding tip and is an elastic body made of a resin or rubber having an insulating property. The teaching tip has a base end into which the distal end portion of the power feeding tip is inserted. A tip housing recessed portion is formed to be allowed to be attached and detached to/from the power feeding tip. The tip housing recessed portion has an abutting surface abutting on the distal end surface of the power feeding tip. A distance along a longitudinal direction from the abutting surface to a distal end of the teaching tip is set to a specified length.

A welding torch has a proximal portion, a distal portion including a contact tip and a diffuser, and a hexapod actuator located between the proximal portion of the welding torch and the distal portion of the welding torch. The hexapod actuator has a moving platform movable with six degrees of freedom and having a central opening through the moving platform. The distal portion of the welding torch is moved by said moving platform in said six degrees of freedom. A wire electrode is fed to the contact tip through the central opening of the moving platform during movement of the distal portion of the welding torch by the moving platform.

A welding torch has a proximal portion, a distal portion including a contact tip and a diffuser, and a hexapod actuator located between the proximal portion of the welding torch and the distal portion of the welding torch. The hexapod actuator has a moving platform movable with six degrees of freedom and having a central opening through the moving platform. The distal portion of the welding torch is moved by said moving platform in said six degrees of freedom. A wire electrode is fed to the contact tip through the central opening of the moving platform during movement of the distal portion of the welding torch by the moving platform.