Design Difficulty Analysis

Most wire forms are fully bespoke parts with unique geometric shapes. No standardized spring calculation formulas can be directly applied. Each design requires independent mechanical analysis, force-stroke verification and fatigue check, which highly relies on engineering experience and finite element analysis (FEA).

Metal wire produces elastic springback after bending, and the springback rate varies greatly with wire diameter, material grade, bending angle and inner bend radius. Achieving accurate forming requires repeated process adjustment and compensation, which increases design iteration and trial production costs.

The stress distribution at bending corners is highly uneven, with obvious stress concentration on the inner side of bends. Under dynamic cyclic loads, fatigue cracks are very likely to initiate at bending points, making fatigue life verification far more complicated than standard coiled springs.

Wire forms usually act as functional mating parts. Their dimensional tolerances directly affect latching force, insertion/extraction force, positioning accuracy and assembly reliability. Tight dimensional control is required for multiple bending positions, which puts forward higher requirements for design precision.

Each wire material has a minimum allowable bending radius determined by its ductility and hardness. Designs beyond the forming limit will cause cracking or excessive work hardening during production. Designers must fully grasp the process boundaries of different materials to ensure manufacturability.