To prevent the working precision from being disturbed caused on the slag piling up on the circumference face of a squeeze roll for welding seam welded pipe.

A scraper 9 which is brought in sliding contact with the circumference face of cylindrical part 7 adjoining to an engaging part 6 with resistance welded tube 5 is installed on the opposite side of a high frequency heating part 2 of a squeeze roll 4 which is arranged just after the high frequency heating part 2 of a production device of seam welded pipe and which restricts the external circumference of the welded pipe 5 to be welded. In this scraper 9, the pressing force against the cylindrical part 7 is regulated with a push screw 12.