针对核乏燃料池水下机器人熔化极气体保护焊接修复需求，研制了一种轻量化 全密封送丝装置． 采用铝合金外壳、玻璃钢面板等实现装置整体轻量化; 采用双驱滚轮送 丝机构，并通过焊丝盘等部件的优化布局实现装置的小型化;通过气管外接压缩气体实现 装置内部压力随水深变化的调节;设计了基于 AＲM 的数字化驱动控制系统，采用电枢电 压负反馈控制和高频斩波技术补偿送丝速度的变化;利用基于 CAN 的数字化通信接口电 路实现与水下机器人的数字化集成． 20 m 深水下焊接试验结果表明: 该送丝装置的壳体 强度高，送丝稳定均匀，响应快速灵敏，工艺适应性好，可满足水下焊接修复要求． 

Aiming at the repair needs of the underwater Ｒobotic MIG welding for nuclear fuel pool，a lightweighted and entirely-sealed wire feeder was developed． The overall lightweighting is achieved by means of aluminum alloy shell，glass steel panel and other devices; the double driving roller wire feeding mechanism is adopted，and the miniaturization of the device is realized through the optimized layout of the components like welding wire tray． The shell is connected with the compressed gas through a trachea to realize the self-adjustment of the pressure of the device with the change of water depth． To compensate the change of wire feeding speed，a digital driving control system based on AＲM is designed which adopted negative feedback control of armature voltage and high frequency chopping technology． The digital communication interface circuit based on CAN is used to realize the digital integration with the underwater robot． Test results of underwater welding at the level of 20 m depth show that the wire feeding device has the advantages of high shell strength，stable and uniform wire feeding，quick response and good adaptability，and thus meet the requirements of underwater welding repair．