MANUFACTURING METHOD FOR WELDED TITANIUM TUBES Russian patent published in 2017 - IPC B21C37/08 B21D22/16 C22F1/18 

FIELD: metallurgy.

SUBSTANCE: tube blank (3) is received by bending flat sheet blank (2) and welding longitudinal edges (1). Rotary rolling of a weld (4) of a tube blank (3) mounted on a rotating mandrel (5) by means of pressing elements (6) of the hard tool (7) is performed. Annealing of welded titanium tube (8) is carried out to remove the residual stresses. Therein rolling of the weld (4) is produced with relative deformation of 8%≤ε≤20% along the wall thickness of tube blank (3), wherein ε=(t₀-t)/t₀×100%, where t₀ is the wall thickness of the tube blank (3), t is the wall thickness of the welded titanium tube (8) after rolling the weld (4) and subsequent annealing - at temperature (T_rs-170)°C≤T_ann≤(T_rs-50)°C which is determined from the range, where T_rs is the temperature of recrystallization start of the titanium alloy,°C.

EFFECT: increased strength and cycle life of welded titanium tubes through the optimal selection of thermomechanical processing parameters for tube round billets.

4 dwg