Do you know how the titanium rod is straightened?
Common alignment methods for titanium rods include: tension straightening, sinus straightening, and pressure straightening.
Tension straightening is a processing method that applies a longitudinal tensile force exceeding a yield limit of a workpiece to a workpiece to cause plastic elongation to achieve shape defect correction, which is also called drawing straightening. At the time of straightening, a tensile stress exceeding the yield limit of the material is applied to the titanium rod, the titanium wire, and the titanium tube having wave shape defects on the tension leveler. The tensile stress is superimposed on the original residual stress of the titanium bar. When the extension is large, part of the tensile stress is cancelled, so that the actual deformation stress is reduced, and the plastic extension is small when straightening; The superposition of the tensile stress increases the actual deformation stress, and the plastic extension is large when straightening. As a result, after the tension is applied, the straightened portions of the workpiece are evenly extended, and the wavy defects are eliminated.
In the production, the sinusoidal straightening method is widely used for the rod wire and the pipe of the simple section. The titanium tube and the titanium rod were carried out on a skew roll straightening machine. The number of rollers of the straightening machine is greater than 4 (usually 5 to 29 rolls), and the working principle is to continuously repeat the three-point bending of the workpiece by each roller, thereby gradually reducing the variation range of the residual curvature of the workpiece.
Sinusoidal straightening is often used in conjunction with pressure straightening. The workpiece with a higher degree of curvature is first straightened by a pressure straightener and then straightened by a skewed roll. The straightening effect depends mainly on the straightener pressure and the roll angle. The magnitude of the pressure depends on the yield strength and tortuosity of the alloy material. In the case of a titanium alloy having a high strength, when the bending degree is large, the straightening pressure should be larger, and vice versa. The size of the roll inclination depends on the diameter of the workpiece, and a workpiece with a large diameter should be larger than a small straightening angle. After the straightening is completed, the unqualified workpiece should be returned and re-straightened. Titanium tubes that cannot be straightened should be straightened