Abstract: The inevitability and feasibility of application of the grouping technique to produc tion bf hi-frequency welded tubes are discussed from both theoretic and practical point of views. With the grouping technique it is allowed to produce a group of tube sizes with similar O. D. s by means of one set of open-pass rolls and sizing rolls in forming and sizing operations,which not only simplifies the preparation procedure for the production, but also cuts down the operation costs.