METHOD OF MANUFACTURING SEAMLESS TUBES FROM CYLINDRICAL BILLETS OF HARD-TO-DEFORM METALS AND ALLOYS Russian patent published in 2018 - IPC B21C23/08 

FIELD: metallurgy.

SUBSTANCE: invention relates to the treatment of metals by pressure and can be used in the manufacture of seamless tubes from cylindrical billets of hard-to-deform metals and alloys, primarily titanium, on horizontal pipe-type presses without a piercing system. Method includes drilling a cylindrical billet, applying a process lubricant, heating the hollow billet, loading the billet into a container, successive operations of expansion of the billet in the container of the press and pressing the tube, separation of the tube from the press residue, according to the invention the expansion of the billet is carried out by an expander, whose diameter is made in accordance with the ratio D_exp=D_int.bill×K_exp, where D_exp - diameter of the expander, mm; D_int.bill - internal diameter of the billet, mm; K_exp - coefficient of expansion (K_exp=1.5-3.5), herewith at the front end of the expander a piercing needle having the length of 1.2-3.0 times the length of the billet is fixed coaxially, and its diameter is 0.980-0.995 of the inner diameter of the guide ring installed in the toolboard holder, after the expansion the container with a press-stem is retracted to its original position, and the toolboard is moved to the next position with a pre-installed press-die, herewith a lubricating washer is placed between the press-die and the expanded billet and pressing of the tube is carried out by the subsequent press stroke.

EFFECT: technical result is the reduction of metal losses in the production of tubes with the relative concentricity of less than 4%.

1 cl, 2 dwg