TWO ELECTRODE SUBMERGED ARC WELDING METHOD FOR PREVENTING HIGH TEMPERATURE CRACK AT HIGH HEAT INPUT FILLET WELDING PART OF ULTRA THICK STEEL FOR STRUCTURAL

摘要

Purpose: a bipolar electrode submerged arc welding method be used to preventing high temperature rupture one extremist's thickness steel of a high heat input fillet welding part because structure setting at prevent the hightemperature cracks of fillet welding part by control bevel angle and welding condition, a thus fillet welding part of the one high-strength thick material of width of the ratio of controlling depth and a welding metal in bipolar electrode submerged-arc welding for foundation. Construction: the method is characterized in that the fillet welding of the steel of a super thick is partly because structure is soldered, by controlling to a ratio of the depth (D) in 1 range and the width (W) of a welding metal: 0.6 to 1: 0.8, using 90 kilojoules/centimetre or more a bevel angle in fillet welding part be a welding heat input under 55 degree of welding condition, the welding current and a weldingvoltage of the electrode previous applied to one are separately arranged as the range of 800 to 950 A and 34 to 36 V, when the welding current and a weldingvoltage that are applied to an adjoint electrode are separately arranged as the range of 650 to 800 A and 38 to 41 V, a speed of welding is set within the scope of 33 to 40 cm per minutes.