US 12,440,927 B1
High-heat-input combined welding method for thick-walled high-strength steel
Lianyong Xu, Tianjin (CN); Yongdian Han, Tianjin (CN); Zhaowei Xue, Tianjin (CN); Lei Zhao, Tianjin (CN); and Kangda Hao, Tianjin (CN)
Assigned to Tianjin University, Tianjin (CN)
Filed by Tianjin University, Tianjin (CN)
Filed on May 27, 2025, as Appl. No. 19/220,069.
Claims priority of application No. 202411161692.8 (CN), filed on Aug. 23, 2024.
Int. Cl. B23K 33/00 (2006.01); B23K 9/16 (2006.01); B23K 9/173 (2006.01); B23K 9/18 (2006.01)
CPC B23K 33/004 (2013.01) [B23K 9/164 (2013.01); B23K 9/173 (2013.01); B23K 9/188 (2013.01)] 5 Claims
OG exemplary drawing
 
1. A high-heat-input combined welding method for thick-walled high-strength steel, comprising:
machining a steel plate to be welded into an asymmetric double-sided V-groove, wherein a depth of a front groove is 30 mm to 40 mm; then filling and welding the front groove using electrogas welding while controlling a single-pass heat input below 300 kJ/cm; and finally filling and welding a back groove while ensuring that the single-pass heat input of the back groove does not exceed that of the front groove,
wherein, when a back groove depth satisfies H2≤25 mm, flux-cored arc welding is configured for filling welding;
when the back groove depth satisfies 25 mm<H2≤50 mm, flux-cored arc welding is first configured for filling welding; when a remaining groove depth h satisfies following formula, electrogas welding is then configured for filling welding,

OG Complex Work Unit Math
in the formula, h represents the remaining groove depth, H2 represents the back groove depth, H1 represents a front groove depth, α1 represents a front groove angle, and α2 represents a back groove angle;
when the back groove depth satisfies H2>50 mm, triple-wire submerged arc welding is first configured for filling welding; when the remaining groove depth h satisfies the formula, electrogas welding is then configured for filling welding,

OG Complex Work Unit Math
in the formula, h represents the remaining groove depth, H2 represents the back groove depth, H1 represents the front groove depth, α1 represents the front groove angle, and α2 represents the back groove angle,
wherein when adopting flux-cored arc welding for filling passes, welding current is within 160A-220A, arc voltage is within 20V-23V, welding speed is 10 cm/min-16 cm/min with heat input of 10 kJ/cm-20 kJ/cm, the electrode extension is within 12 mm-15 mm, and the gas current is at 15 L/min-25 L/min,
wherein when performing filling welding using triple-wire submerged arc welding, leading wire welding current is 1160A-1380A with welding voltage of 32V-35V; middle wire welding current is 1100A-1280A with welding voltage of 40V-42V; trailing wire welding current is 950A-1200A with welding voltage of 42V-46V; triple-wire submerged arc welding speed is 35 cm/min-81 cm/min with heat input of 90KJ/cm-260KJ/cm.