METHOD OF FABRICATING THIN-WALLED PIPES Russian patent published in 2010 - IPC B21C1/24 

FIELD: mechanics.

SUBSTANCE: invention relates to improvement of accuracy in dimensions of precision pipes sections, for instance from corrosion-resistant steels for shells of fuel elements in nuclear reactors. Method includes pipe drawing in cone draw die on fixed cylindrical mandrel. Stability of pipes dimensions and reduction of elastic and thermal deformation are provided by the fact that at first pipe billet is rolled and drawn without mandrel, and afterwards drawing of pipe is carried out in fixed cylindrical mandrel, when drawing coefficient along section of pipe λ makes 1.25≤λ≤1.48, at the same time coefficient of drawing along pipe wall λ_s makes 0.90λ≤λ_s≤0.94λ.

EFFECT: increased accuracy of precision pipes section dimensions.