国精产品一区一区三区,97久久精品无码一区二区,欧美老妇大P毛茸茸,两根黑人粗大噗嗤噗嗤视频

GB6479??????ù?|20#??????ù?|????????ù?

??????ù?
    ??????ù??GB6479-2000??????????豸?????????????????????豸???????????????????????????20??16Mn??12CrMo??12Cr2Mo???
??????????ù??GB6479-86?????????????????-40~400?楨????????10~30Ma??????豸?????????????????????????
?????????豸?????????GB6479-86?????????????????-40~400?楨????????10~30Ma??????豸??????????????????????????
???????????????硢?????????????????????????????Q235A??B?????GB/T14980-1994????????????????????紙????????ˉ?????????????????????ú???????????????????????????????????????????Q235A?????
??????????????????????????
??????б????GB6479-2000??ASTM DIN JIS
????????????20# 16Mn??15CrMo,12CrMo??12Cr2Mo??
????4.?????????
????(1)GB3087-82?????????ˉ?????????漲???????????鷽????GB222-84??GB223???????????????????????е??й?????
????(2)GB5310-95???????ˉ?????????漲???????????鷽????GB222-84??????????????????????????GB223???????????????????????е??й?????
????(3)?????ˉ???????????鰴????漲???й??????С?
????5.??ˉ???????
????(1)??????????????20G??20MnG??25MnG??
????(2)????????15MoG??20MoG??12CrMoG??15CrMoG??12Cr2MoG??12CrMoVG??12Cr3MoVSiTiB???
????(3)????????????1Cr18Ni9??1Cr18Ni11Nb??ˉ??????????????е?????????????????飬??????????????顣??????????????????
????????????????????????????????????????????
????6.???????????
????(1)GB3087-82?????????ˉ?????????漲?????????鰴GB/T228-87???????鰴GB/T241-90????????鰴GB/T246-97?????????鰴GB/T242-97?????????鰴GB244-97??
??????????ù??????????[(??-???)*???]*0.02466=kg/?????????????

?????????????????ù????????GB6479??GB9948?????? |?????豸??????????GB6479-1999????