In order to meet the lightweight design requirements of one swing-type plate shears, the topology optimization method is applied to improve the structure of bed. According to the analysis of the actual working conditions, the reasonable load and boundary conditions are determined. The conceptual model of bed structure is established by using topology optimization method. Lightweight improvement scheme is proposed based on the topology optimization results, and the rationality of scheme is verified by test and analysis. Different parts of the bed are thickened or thinned, and the influences of different thickness of the stiffener on the maximum principal stress, total displacement, displacement in Y direction and weight of bed structure model are analyzed. A reasonable lightweight scheme of shear machine bed is proposed. The weight of the bed is reduced and the lightweight purpose is finally achieved in the case of meeting the requirements of shearing accuracy.

CNC hydraulic swing-type plate shears is one of the important plate processing equipments, whose safety performance and shearing accuracy are determined by the structure of its frame and tool carrier. The current mechanical property analyses of plate shears mostly only use finite element tools and simply apply uniform load, which can not reflect true work status of the plate shears. By integrating original structures of the frame and tool carrier, two working status’ static performances of the plate shears are analyzed with finite element method in this paper, where the uniform load or moving load are separately applied according to its work statue. The analysis results are verified by the later stress-strain tests according to which structural improvements are proposed to provide basis for improving properties of the plate shears.