METHOD AND APPARATUS FOR STUD WELDING COUPLER SOCKET OF LNG CARRIER

摘要

PURPOSE: A method and an apparatus for stud welding coupler socket of LNG carrier are provided to secure proper welding quality without removal of shop primer of welding portions, shorten a production term of works of the LNG carrier and reduce fatigue of workers. CONSTITUTION: In welding a coupler socket to cargo tank of LNG carrier, the method for stud welding the coupler socket of the LNG carrier comprises a step (710) of internally welding the coupler socket having diameter of 40 mm to a chuck which is positioned the central inner part of a stud gun, and in which stud is equipped; a step (S720) of contacting four guide lines with welding position of base metal so that the four guide lines are supported to the welding position of base metal, wherein the four guide lines are symmetrically arranged with being positioned at the outer side of the stud gun so that the coupler socket is attached to its regular position; a step (S730) of contacting the welding part of the coupler socket with the base metal with a welding distance being maintained therebetween as the chuck is being pressed by a pressing spring of the inner rear side; a step (S740) of impressing a power source to the stud gun in the state that the welding part of the coupler socket is pressed so that the welding part of the coupler socket touches the surface of the base metal; a step (S750) of melting protrusion of the coupler socket; a step (S760) of melting thus welding the welding part of the coupler socket comprising the protrusion onto the base metal; and a step (S770) of releasing pressing into the chuck when welding of the coupler socket is completed, thereby separating the coupler socket from the stud gun.