METHOD AND APPARATUS FOR PRODUCING THIN TUBES IN A SKEW-ROLLING MILL

摘要

The present invention relates to a method and rolling mill for producing a thin walled tube. In the method a blank is rolled between skewed rollers having cooperating rolling surfaces define high points which upon contact with the blank reduces the wall to samll thickness relative to the outer diameter of the rolled tube. Shortly before the end of the blank is introduced into the rolling area, the rotation axis of the rollers are pivoted about a point remote from the rolling area to reduce the adjustment angle between the rotation axis of the inclined rollers and the axis of the rolled tube which causes an enlargement of the rolling area. According to the invention, in order to obviate the production of tubes having thickened ends, a further movement is imposed in the skewed rollers at right angles to the direction of rolling. In the rolling mill of the invention, means are provided for adjusting the skewed rollers orthogenally relative to the work Piece. Means are provided for effect simultaneous change in the inclined position of the rollers through rotation of a rotatable flange and for causing a simultaneous operation of the roller adjusting means.