back welding

例句：

1. 1. The engineer used a special tool to perform the back welding on the damaged part.
   工程师使用一种特殊工具对损坏的部分进行反向焊接。
2. 2.Back welding is an essential process in the manufacturing of metal parts.
   反向焊接是金属部件制造过程中的一个必要步骤。
3. 3.During the assembly process, it's important to ensure that all components are properly back welded together.
   在装配过程中，确保所有组件正确焊接在一起是很重要的。