The technical transformation practice in copper mineral processing plant in recent years was mainly introduced, And the successful experience was summed up so as to be used for spot produce.
介绍近年来铜选厂的技改实践，总结成功经验，供现场生产借鉴。
2
This paper discusses the source of heat for spot welding and the theory of diffusion welding of brass and red copper.
探讨了点焊热量的来源和黄铜与紫铜的扩散焊机理。
3
Spot welding procedure of copper with inlaid filler metal sheet HL204 is introduced, too.