Transverse buckling of a strip in continuous annealingproduction line (CAPL) has been investigated. Transversebuckling occurs when the induced compressive stress resultingfrom non uniform longitudinal stretching in the strip exceedsa critical buckling stress. The MARC software has been usedalong with a buckling nonlinear geometrical analysis. Themechanisms of major factors, such as roll profile, flatness,strip size, transverse distribution of temperature, weldingseam and strip track-off are reported. The average houroutput increased by 5.89% through a series of technicaldevelopments.