Abstract:The change of production of the bar steel plant requires that the flying shear set is modified independently. The modification should meet the demand for the technology change, reducing the impact on the main operating line and lowering the cost of modification as much as possible. Intensity of original main body of flying shear, shearing structure and gear box was analyzed and calculated to be modified by salvaging. The electric motor, coupling, flywheel, gear pair and bearing were modified by designing new product. The modified flying shear set meets the demand for production technique.