摘要 |
A roll pass of a roll set having three rolls for a multi-stand mandrel-free stretch reducing mill has a roll pass shape that deviates from the circular. A tube is passed in its longitudinal direction through the non-circular roll pass shape enabling modification of a shape of a cross-section of the tube, so as to counteract the non-circular external diameter deviations of the tube. A final roll pass (finishing pass) of the stretch reducing mill is locally enlarged at peripheral points where the tube diameter of the entering tube would otherwise deviate downward from a target size and locally reduced in size at the peripheral points where the tube diameter would otherwise deviate upward from the target size.
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