CN-121972763-A - Welding method for thick high-strength wear-resistant steel NM450

Abstract

The invention discloses a welding method of thick high-strength wear-resistant steel NM450, which adopts 80 percent Ar+20 percent CO 2 argon-rich mixed gas and solid HS-80 rare earth welding wires with the diameter of 1.2mm for shielded welding, the preheating temperature before welding is 50-150 ℃, the welding current is controlled at 260-280A, the welding voltage is controlled at 30-32V, the welding speed is controlled at 5-5.5mm/s, the gas flow is 18-20L/min, and the dehydrogenation treatment is carried out after welding for 220 ℃ multiplied by 3h. The invention ensures good impact toughness and quality of the thick abrasion-resistant steel weld seam by adopting rare earth welding wires for welding and post-welding dehydrogenation treatment.

Inventors

• WANG SHAOBING
• WEI HUIHUI
• YUAN XIAOMING
• WANG QINGMIN
• HUANG LI
• Yue Dainan
• WANG TING
• LU XIAOYU
• YANG XIONG
• LI PENG

Assignees

• 内蒙古包钢钢联股份有限公司

Dates

Publication Date

20260505

Application Date

20260112

Claims (8)

1. 1. A welding method of thick high-strength wear-resistant steel NM450 is characterized in that NM450 wear-resistant steel plates with the thickness of 40-60mm are adopted, 80 percent Ar+20 percent CO 2 argon-rich mixed gas and HS-80 rare earth welding wires are adopted for welding, The welding groove adopts a symmetrical double-sided X-shaped groove, the angle of a single-sided groove is 30 degrees, the blunt edge is 2mm, and the gap of the groove is 3mm; Preheating a steel plate before welding, wherein the preheating temperature is 50-150 ℃, the welding process sequence is that 1, 2 and 3 welding lines are used as backing welding, after the 1 st and 2 welding lines are completed, turning over, back gouging by an angle grinder, ensuring that the back gouging is thorough, completely exposing the metallic luster, finishing the 3 rd back-off welding after checking no crack defect, then finishing other welding lines, and carrying out 220 ℃ multiplied by 3h dehydrogenation treatment after welding; the welding current is controlled at 260-280A, the welding voltage is controlled at 30-32V, the welding speed is controlled at 5-5.5mm/s, the inter-channel temperature is 145-155 ℃, and the gas flow is 18-20L/min.
2. 2. The method for welding thick high-strength wear-resistant steel NM450 of claim 1, wherein the diameter of the welding wire is phi 1.2mm, and the content of rare earth LaCe is 30ppm.
3. 3. The welding method of thick high strength wear resistant steel NM450 of claim 1, wherein the thickness of the wear resistant steel plate is 45mm, the steel plate is preheated before welding, and the preheating temperature is 80 ℃.
4. 4. The welding method for thick high-strength wear-resistant steel NM450 of claim 3, wherein the welding current is controlled at 260A, the welding voltage is controlled at 30V, the welding speed is controlled at 5mm/s, the inter-channel temperature is 145 ℃, and the gas flow is 18L/min.
5. 5. The welding method of thick high strength wear resistant steel NM450 of claim 1, wherein the thickness of the wear resistant steel plate is 50mm, the steel plate is preheated before welding, and the preheating temperature is 150 ℃.
6. 6. The welding method of thick high strength wear resistant steel NM450 of claim 5, wherein the welding current is controlled to 280A, the welding voltage is controlled to 32V, the welding speed is controlled to 5.5mm/s, the inter-channel temperature is 155 ℃, and the gas flow is 20L/min.
7. 7. The welding method of thick high strength wear resistant steel NM450 of claim 1, wherein the thickness of the wear resistant steel plate is 60mm, the steel plate is preheated before welding, and the preheating temperature is 120 ℃.
8. 8. The welding method for thick high strength wear resistant steel NM450 of claim 1, wherein the welding current is controlled to 270A, the welding voltage is controlled to 30V, the welding speed is controlled to 5.2mm/s, the inter-channel temperature is 150 ℃, and the gas flow is 19L/min.

Description

Welding method for thick high-strength wear-resistant steel NM450 Technical Field The invention belongs to the technical field of wear-resistant steel, and particularly relates to a welding method of thick high-strength wear-resistant steel NM 450. Background The wear-resistant steel has high strength and high hardness, is widely applied to various engineering mechanical equipment, generally adopts high carbon and high alloy components, has larger carbon equivalent and is easy to generate welding cracks in the welding process, so the weldability of the wear-resistant steel is also important, and in addition, for thick wear-resistant steel with low core impact toughness, the wear-resistant steel after being welded not only meets the requirements on performance, but also ensures safety and reliability, and has important significance in researching the welding method of the wear-resistant steel. Patent CN 118808834A discloses a welding method of wear-resistant steel NM450, provides a welding method of wear-resistant steel NM450 with lower cost, has better weld quality and welding joint performance, reduces weld strength, and requires-20 ℃ impact on the existing wear-resistant steel weld. Patent CN 114309899A discloses a welding method of low alloy wear-resistant steel and a welded joint thereof, wherein double-filament submerged-arc welding is adopted for backing and filling welding, cold filament filling double-filament submerged-arc welding is adopted for capping, and the comprehensive mechanical property of a welding line is ensured, but the welding line strength is not provided in the invention, and the impact toughness of the welding line is lower. Disclosure of Invention The invention aims to provide a welding method of thick high-strength wear-resistant steel NM450, which adopts 80 percent Ar+20 percent CO 2 argon-rich mixed gas and HS-80 rare earth welding wire for shielded welding, the preheating temperature before welding is 50-150 ℃, and the hydrogen elimination treatment is carried out after welding for 220 ℃ multiplied by 3 hours, so that the good quality and performance of a welded joint are ensured. In order to solve the technical problems, the invention adopts the following technical scheme: The invention relates to a welding method of thick high-strength wear-resistant steel NM450, which adopts a NM450 wear-resistant steel plate with the thickness of 40-60mm, adopts 80 percent Ar+20 percent CO 2 argon-rich mixed gas and HS-80 rare earth welding wires for welding, The welding groove adopts a symmetrical double-sided X-shaped groove, the angle of a single-sided groove is 30 degrees, the blunt edge is 2mm, and the gap of the groove is 3mm; Preheating a steel plate before welding, wherein the preheating temperature is 50-150 ℃, the welding process sequence is that 1, 2 and 3 welding lines are used as backing welding, after the 1 st and 2 welding lines are completed, turning over, back gouging by an angle grinder, ensuring that the back gouging is thorough, completely exposing the metallic luster, finishing the 3 rd back-off welding after checking no crack defect, then finishing other welding lines, and carrying out 220 ℃ multiplied by 3h dehydrogenation treatment after welding; the welding current is controlled at 260-280A, the welding voltage is controlled at 30-32V, the welding speed is controlled at 5-5.5mm/s, the inter-channel temperature is 145-155 ℃, and the gas flow is 18-20L/min. Further, the diameter of the welding wire is phi 1.2mm, and the content of rare earth LaCe is 30ppm. Further, the thickness of the wear-resistant steel plate is 45mm, and the steel plate is preheated before welding, and the preheating temperature is 80 ℃. Further, the welding current was controlled at 260A, the welding voltage was controlled at 30V, the welding speed was controlled at 5mm/s, the inter-track temperature was 145℃and the gas flow was 18L/min. Further, the thickness of the wear-resistant steel plate is 50mm, and the steel plate is preheated before welding, and the preheating temperature is 150 ℃. Further, the welding current was controlled at 280A, the welding voltage was controlled at 32V, the welding speed was controlled at 5.5mm/s, the inter-track temperature was 155℃and the gas flow was 20L/min. Further, the thickness of the wear-resistant steel plate is 60mm, the steel plate is preheated before welding, and the preheating temperature is 120 ℃. Further, the welding current was controlled at 270A, the welding voltage was controlled at 30V, the welding speed was controlled at 5.2mm/s, the inter-track temperature was 150℃and the gas flow was 19L/min. Compared with the prior art, the invention has the beneficial technical effects that: (1) By adopting the rare earth welding wire for welding, the rare earth can refine weld grains, improve the low-temperature impact toughness of the weld, and solve the problem of low impact toughness of the thick abrasion-resistant steel weld. (2) For thick wear-resista