The traditional closed barrel terminal and the cable are crimped by one-time crimping method, and the whole model can be simplified into a simply supported beam. Although the pressure F on the entire terminal crimping section remains basically unchanged, the moment M (=FL) is also different due to the difference in the length L of the force arm (with the step surface as the fulcrum) (L1>L2>L3) (M1>M2> M3). According to the force theory of simply supported beams, the bending moment at the crimping section L/2 is the largest, resulting in different crimp heights (that is, the cross-sectional height of the crimped part of the connector terminal and the terminal after the cable is crimped), which makes the crimping height different. The real contact area after the connection is only a very small part, which is only equivalent to line contact. This seriously affects the electrical and mechanical properties of automotive high-voltage wiring harnesses with large cable cross-sectional area, high tensile performance requirements, and long crimping length (ie, the contact length between the connector terminal and the cable after crimping).