氮杂杂环化合物
azo-heterocyclic compounds
18—18护环钢
18-18 steel for retaining ring
18—5护环钢
18-5 steel for retaining ring
H型钢钢混叠合梁
H-formed steel concrete composite girder
Mn18Cr18N护环钢
Mn18Cr18N retaining ring steel
Mn18Cr18N Steel for Retaining Ring
X70管线钢环焊接头
girth joint of X70 pipeline steel
玻璃钢-钢抽油杆
Fiberglass-steel Sucker Rod
玻璃钢—钢混合抽油杆
fiberglass—steel sucker rod string
不锈钢除尘灰
dust from stainless steel
stainless steel dedust ash
stainless steel dust