三门峡水利枢纽工程既是建国初期重要的工程项目,也是当时中苏友好背景下的国际化工程,具有重要的社会影响和国际影响。鉴于运输需求,原定于苏联制造的大型水轮机转子被分解切割,本计划邀请苏联专家亲临三门峡现场进行焊接,随后组装水轮机组。然而,随着中苏关系的骤然恶化,苏联专家撤出,这使得水轮机转子的成功焊接成为三门峡水电站正常投入使用的关键技术问题。当时中国的焊接技术处于引进学习的起步阶段,从未进行过这种大体积、大厚度工件的高难度焊接,而且水轮机转子是一个孤件,如果焊接失败,这个关键部件将报废,三门峡工程可能前功尽弃。为此,国家聚集全国的焊接技术力量进行试验技术设计,比较多家提供的试验方案后,哈工大提供的方案得到了国家领导和工程管理部门的认可。哈工大的焊接专家和青年教师在极端困难的条件下圆满地完成了这项高难度的焊接工程。焊接的成品质量高于苏联专家的设计要求。这提振了国家领导人对我国新生的焊接技术专业水平的信心,也为后续的新安江、刘家峡等我国自主建设的大型水利枢纽设施提供了技术基础和保障。除了收集和梳理史料外,本研究大量内容来源于该工程主要参与者的口述史访谈。

The Sanmenxia Water Conservancy Project was not only a landmark engineering feat in the early days of the People's Republic of China but also a significant international collaboration during the period of Sino-Soviet friendship. This article, based on oral histories from participants in the welding engineering of the segmented rotor of the Sanmenxia turbine, delves deeply into the core technical challenge faced by the project—the welding of the turbine rotor—and how Chinese welding technicians overcame this difficulty after the withdrawal of Soviet experts. Through this typical case study, the article reveals the complex and profound interplay between international relations, political factors, and engineering technical practices.The Yellow River's frequent flooding had long been a major concern for the national government, making its governance a crucial task for the New China. In the "Initial Opinions on Governing the Yellow River", it was explicitly proposed that constructing a reservoir at Sanmenxia was the key method to eliminate the threat of downstream flooding. During the Sino-Soviet friendship period, the Sanmenxia Water Conservancy Project was listed as one of the key projects aided by the Soviet Union, with the latter responsible for the design and supply of equipment. However, with the rupture of Sino-Soviet relations and the sudden withdrawal of Soviet experts, the project encountered severe technical challenges, particularly in the welding of large-volume, thick turbine rotors.Due to the withdrawal of Soviet experts, China lacked the necessary experience and technical reserves for large-scale hydropower station construction. The welding of the turbine rotor became a critical factor determining the success or failure of the Sanmenxia Water Conservancy Project. The national leadership attached great importance to this issue and promptly organized the country's top technical forces for joint research. Ultimately, Harbin Institute of Technology (HIT) was selected to provide the welding solution. Taking into account China's actual engineering and technical capabilities, the Welding Research Section of HIT collaborated with other units to jointly develop a detailed welding test plan.After numerous repeated tests and verifications, HIT's welding solution gained widespread recognition and was entrusted with the actual welding work. Under extremely arduous conditions, the welding experts and young faculty members of HIT rose to the challenge and successfully completed the high-difficulty welding task of the turbine rotor. Through multiple rigorous test verifications, the welding quality was ensured, not only meeting but also surpassing the design requirements of Soviet experts. This technical breakthrough not only significantly enhanced China's welding technology level but also provided solid technical support and guarantees for the subsequent construction of large-scale water conservancy projects such as Xin'anjiang and Liujiaxia. The success of the turbine rotor welding at Sanmenxia marked China's capability to independently install and operate large-scale hydropower station generator sets, an achievement with profound political and economic significance. For this, the State Council specifically issued a citation of merit to Harbin Institute of Technology in recognition of its outstanding contributions in the field of technology. Furthermore, HIT's welding technology laid a solid foundation for the subsequent development of China's aerospace engineering and other fields. In summary, the technical breakthrough in the welding of the turbine rotor in the Sanmenxia Water Conservancy Project was not only a major technological achievement but also a symbol of China's adherence to independent innovation and its courage to climb the peak of science and technology under international relations and political pressure. This event fully demonstrated the firm determination and outstanding wisdom of the New China in facing technological challenges, exerting a far-reaching and positive impact on the country's modernization construction.