Tube bending deforms straight tubes into curved ones. Excessive thinning in tube bending (typically at bend extrados) is not desirable since it may lead to tearing in bending or premature bursting in the subsequent hydroforming stage. To compensate for the thinning during tube bending a boosting force is typically applied to one tube end, which introduces a net compression in the tube section. The amount of boosting is limited by the tendency of tube material to wrinkle. In this paper a finite element model is developed to simulate rotary draw tube bending and the 2nd-order normal velocity difference among neighboring points is used for wrinkling detection. The evolution of the developed wrinkling Indicator is correlated with the initiation and growth of wrinkles in simulations. Two wrinkling modes, before the material enters the bending die and at the bending zone, are identified under different pad pressures and boosting conditions. The algorithm provides a basis for determining an optimal adaptive loading scheme to prevent wrinkling failure in tube bending.