【作者】 周灿丰； 焦向东； 何峰； 李小岗； 许维青； 王百泉； 李其修； 蒋建敏；

【Author】 Zhou Canfeng;Jiao Xiangdong;He Feng;Li Xiaogang;Xu Weiqing;Wang Baiquan;Li Qixiu;Jiang Jianmin;Engineering Research Center of Beijing Colleges,Advanced Connection Technology of Energy Engineering,Beijing Institute of Petrochemical Technology;Beijing Underground Transit Line Project Department,China Railway Tunnel Group Co.Ltd.;School of Naval Architecture and Power Engineering,Naval University of Engineering,PLA;College of Materials Science and Engineering,Beijing University of Technology;

【机构】 北京石油化工学院能源工程先进连接技术北京市高等学校工程研究中心； 中铁隧道集团北京地下直径线项目部； 海军工程大学船舶与动力学院； 北京工业大学材料科学与工程学院；

【摘要】 磨损的盾构刀盘需要进行焊接维修,对于不能开舱进行常压维修的场合,需要采用高压焊接技术。文章介绍了盾构刀盘在隧道内高压环境下的维修技术原理,并提出选择空气潜水和焊条手工焊作为北京地下直径线项目盾构刀盘的维修方案;针对水下干式高压焊接技术研究较少的焊条手工焊,进行了压缩空气环境爆炸燃烧性能试验研究。试验结果表明,压缩空气具有显著的助燃能力,但是在0.6 MPa的压力范围以内,只要把可燃物浓度控制在体积比为5.60%以下,则不会产生爆炸。在北京地下直径线项目盾构的气垫舱内进行了0.15 MPa,0.22 MPa和0.3 MPa压力下的焊条手工焊与碳弧气刨工艺试验也表明,焊工作业过程安全,焊接过程顺利,焊接试件质量符合水下焊接标准AWS D3.6M:1999的要求。实践证明,在压缩空气环境下焊接技术在盾构刀盘维修中具有广阔的应用前景,在0.17 MPa压力之下,可以很好地完成筋板切割、冲刷管切割和焊接以及部分刀具的维修等作业。更多还原

【Abstract】 As the shield cutter head needs welding repair when it is worn,and hyperbaric welding technique should be used in the case chamber cannot be opened for maintenance under normal pressure.This paper introduced the technical principle of cutter-head maintenance in hyperbaric environment,presented the maintenance plan of air diving and SMAW&MMA for the Beijing underground transit line project.The explosion combustibility test under compressed air was carried out in view of less study of SMAW&MMA of underwater dry-type hyperbaric welding technique,and the test results show that compressed air is a good combustion improver,yet explosion would not occur if volume ratio of combustible concentration is less than 5.6% when air pressure is not more than 0.6 MPa.Additionally a technological test of SMAW&MMA and carbon arc gouging was conducted in air cushion chamber at pressures of 0.15 MPa,0.22 MPa and 0.3 MPa respectively,the process of welding operation was safe and successful,the quality of welded specimens met the welding technical requirements of AWD D3.6M;1999.This welding technique under compressed air can be widely applied in maintenance of cutter-head,which will fully complete the tasks like rib plate cutting,flush pipe cutting,welding and maintenance work of cutting tools.更多还原