Having been practiced for several years, a new butt method for spiral welded pipe, the two spots tack-weld butt was made out.

通过几年来的实践，摸索总结出了一种螺旋焊管对接新方法——两点点固对接法。

youdao

Having been practiced for several years, a new butt method for spiral welded pipe, the two spots tack-weld butt was made out.

通过几年来的实践，摸索总结出了一种螺旋焊管对接新方法——两点点固对接法。

youdao