METHOD OF MAKING PIPES FROM AUSTENITIC STEELS WITH A FINE-GRAINED STRUCTURE BY DISTRIBUTION ON A CONE-SHAPED CORE Russian patent published in 2020 - IPC B21D51/10 B21D41/02 B21D39/08 

FIELD: metal forming.

SUBSTANCE: invention relates to metal forming and can be used in production of pipes from austenitic steel. Preliminary tube billet is processed till structure with grain size is no less than No. 3 and its inner surface is lubricated. Billet is installed with provision of contact with lead cone of cone-shaped core fixed on end of mandrel. Core is heated with an inductor. Method includes induction local heating of workpiece to temperature of 1000-1050 °C at a rate of not less than 200 °C/h and its distribution by pushing by means of movable traverse of press on core. Work piece is subjected to pushing in specified temperature range with deformation degree of 15-40% and deformation rate of not more than 10^-3s^-1.

EFFECT: result is improvement of the obtained products quality.

1 cl, 2 dwg, 2 tbl