International thermonuclear experimental reactor correction coil cases are made of heavy, thick, high strength, and high toughness austenitic stainless steel 316LN. The BTCC (bottom and top correction coils) case has the dimension of 2.5 × 7 m2 and cross section of 239.8 × 146.7 mm2, side correction coil case has the dimension of 7.2 × 7.6 m2 and cross section of 147.8 × 168 mm2, and they will be closure welded after winding pack insertion. The 20 mm welding depth, dozens of meter of welding length, strict welding requirements, large size, and complex configuration bring a big challenge to this closure welding work. 20 kW high power laser welding is selected as the main welding method because of the advantage of potential welding deformation control and its penetrating ability and cracking resistance. The welding parameter is developed that can cover the assembly gap from 0 to 0.5 mm with a good welding quality. A special test coupon is designed for the welding procedure qualification, and related tests a...

中文翻译：

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20千瓦激光焊接应用于国际热核实验堆校正线圈外壳焊接

国际热核实验堆校正线圈外壳采用重、厚、高强度、高韧性的奥氏体不锈钢316LN。BTCC（底部和顶部校正线圈）外壳尺寸为 2.5 × 7 m2，横截面为 239.8 × 146.7 mm2，侧面校正线圈外壳尺寸为 7.2 × 7.6 m2，横截面为 147.8 × 168 mm2，它们将在绕组包插入后封闭焊接。20毫米的焊接深度、几十米的焊接长度、严格的焊接要求、大尺寸、复杂的配置给这项封闭焊接工作带来了很大的挑战。20kW大功率激光焊接因其潜在的焊接变形控制及其穿透能力和抗裂性的优势而被选为主要焊接方法。开发的焊接参数可以覆盖0-0.5mm的装配间隙，焊接质量良好。专门为焊接工艺评定设计了一个试件，相关的测试...