METHOD OF MAKING TUBE ARTICLES Russian patent published in 1994 - IPC

FIELD: mechanical engineering. SUBSTANCE: tube skelp is deformed on a tapered punch with a burnishing tool. From the side of the smallest diameter of the working area the punch has a calibrating area made of two opposite directed tapered areas with a cylindrical area located between them. The diameter of the cylindrical area is equal to the largest diameter of the tapered working area. The blank is deformed by burnishing on the punch with a matrix sloped at a small angle to the punch axle and gaining the movement of circular burnishing from a special mechanism. After that the punch with the blank is extracted from the matrix, and the stamped article is removed from the punch shifting the pusher downwards relative to the punch. At the same time the expansion of the article is exercised with the tapered area of the calibrating member facing the smallest diameter of the tapered working area of the punch. The hole calibration is carried out with the cylindrical area of the calibrating member whose diameter is equal to the largest diameter of the tapered working area of the punch. As a result the inner surface of the article assumes a cylindrical form, the outer surface obtains a tapered for, . As the deformation degree of the blank during the expansion is rather small, the effort of the removal of the stamped article from the punch is not large either. The method is used when producing thin-walled tube articles. EFFECT: facilitated manufacture. 1 cl, 3 dwg