gongxutong.cn-中文字幕无码AV波多野吉衣,五月丁香啪啪,少妇久久久久久被弄到高潮,国产亚洲Av无码AV男人的天堂

NEWS

Record the continuous progress of Hongkui metal

Whats the general weight of copper ingot?
  • Date:2022-05-25
  • Read:2469
Crude copper:
Non ferrous metal industry standard of the people's Republic of China YS / T 70-93
① The main component is copper plus silver, not less than 96%, up to 99.3%;
② The main impurity elements are arsenic, antimony, bismuth and lead;
③ For refining;
④ It is in ingot shape, 30 ~ 50kg per ingot.
Other copper ingots can be available from 15 to 300 kg according to customer requirements.
Prev

Problems needing attention in polishing brass

Next

Classification, characteristics and general use of copper