Method for welding half coil of reactor

A method of welding a half coil of a reactor, comprising:

• a temporarily welding step of temporarily welding a half coil onto a circumferential surface of a reactor body;
• and
• a gas metal arc welding (GMAW) step of performing the GMAW on the half coil after the temporary welding is finished,
• wherein the GMAW step is to perform welding to prevent a gap from forming between the half coil and the reactor body using the GMAW which supplies a wire of the same material as the reactor body using an automatic welding machine,
• wherein the gas metal arc welding (GMAW) is performed while performing a weaving operation at a constant width using a welding torch, and welding is performed while performing the weaving operation in a radial direction of the half coil, and
• wherein the weaving operation provides dwell time in a state in which the welding torch becomes the closest to the half coil to increase a formation amount of back beads on an opposite side of the GMAW, and the dwell time is between 0.1 and 0.5 seconds.