Common round steel or steel tube may be rolled into solid or hollow twist drill rods by using the said rolling mill.

普通元钢或普通钢管经此轧机后，可直接变成实心或空心麻花钻杆钢。

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Common round steel or steel tube may be rolled into solid or hollow twist drill rods by using the said rolling mill.

普通元钢或普通钢管经此轧机后，可直接变成实心或空心麻花钻杆钢。

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