The forming and sizing mill rolls the steel strip to pipe shape by roll-forming or cage-forming and welds it to longitudinal welded-pipe with high frequency induction (or contact) heating.

• 成型定径机是将不同规格的带钢,经辊式或排辊式成型,连续卷成相应的直缝管坯,用高频感应(或接触)加热,将管坯焊接成直缝钢管。