A METHOD OF A WELDING

The present invention relates to a welding method comprising: a step for preparing a first and a second member for butt welding; a step for primary chamfering to process each welding end of the first and the second member at an angle; a step for comparing a first thickness with the thickness of either the first member or the second member; a step for comparing a second thickness with the thickness difference between the first member and the second member; a step for checking that the thickness of the first member is less than or equal to the first thickness and the thickness of the second member is greater than the thickness of the first member by less than the second thickness; a step for secondary chamfering to process the welding end of the second member, which is relatively thick, to be thinner than the welding end of the first member; and a step for weld-combining the first member and the second member with an I technique. According to the present invention, the welding method can reduce man hours, welding materials, and welding time since the I technique which is a lower welding technique than a Y technique can be applied by chamfering a welding end of a member having a thickness, to which the I technique cannot be applied, between two members for butt welding having a thickness difference, to which a chamfering process cannot be applied, to a thickness limit for chamfering or a greater thickness. [Reference numerals] (AA) Start; (BB) End; (S10) Prepare a first member and a second member for butt welding; (S20) Perform primary chamfering to process each welding end of the first member and the second member at an angle; (S30) Compare a first thickness with the thickness of either the first member or the second member; (S40) Compare a second thickness with the thickness difference between the first member and the second member; (S50) Check that the thickness of the first member is less than or equal to the first thickness and the thickness of the second member is greater than the thickness of the first member by less than the second thickness; (S60) Perform secondary chamfering to make the second member which is relatively thick into a welding end relatively thin compared to the thickness of the welding end of the first member; (S70) Weld-combine the first member and the second member with an I welding technique