快速导航
????????????阻??????????
来源：�??? 发布日期：2023-03-29 09:54:20
1??
?????GB/T 27840-2021/2011???C?? ????3.5T?????????????
1????
�??????�??GB/T 27840-2021/2011??????C???? ????????3.5T?????????????????????�????
2????????
2.1??标�????�???????????????????�???????????卑????�?????�????????????作????
2.2???�?????�???????�??????�?????P??????P?????�???�????????????
2.3??????????????�??????????????�???????????????????????�?????�????作??
2.4 ????????????�??�?�??4??
2.5 ???�??????????????阻??????????????????????????????
3????组????
标?????�?�?????�????????
