3.管材:均采用焊接钢管(以公称直径DN表示),焊接接口的翻译：3. pipe: are made of welded steel pipes (expressed in nominal diameter DN), weld interface 什么意思？中文翻译英文，英文翻译中文，怎么说？

青云英语翻译

Pipe: are made of welded steel pipe (nominal diameter dn), welding interface

3. pipe: are made of welded steel pipes (expressed in nominal diameter DN), weld interface

3. tubing: Uses the welded steel pipe (by the nominal diameter DN expression), welding connection

3.: tubes are welded steel tube (in nominal diameter DN), solder interface

3. pipe: are made of welded steel pipes (expressed in nominal diameter DN), weld interface