短語詞組短語spiral welded casing 螺旋焊接套管flow coefficient of spiral -casing 蝸殼流量系數(shù)velocity coefficient of spiral -casing 蝸殼流速系數(shù)metallic spiral casing 金屬蝸殼radius of spiral casing 蝸殼半徑spiral casing centralizer 套管旋流扶正器semi spiral casing 不完全蝸殼spiral casing embedded forme 蝸殼埋設(shè)方式reinforced concrete spiral casing 鋼筋混凝土蝸殼 返回 spiral casing