Abstract: Herein, we addressed the problem of short service-life of vacuum circuit breaker (12 kV-1250 A-31.5 kA) in industrial applications, especially in steel plants and switching capacitor banks.The original work was design optimization of the spring manipulator, comprissing the closing/opening, contact-pressure springs, damper, transmission and lubrication units.The weak mechanical links were singled out via numerical simulation and fatigue test to improve the mecahnical life of vacuum circuit breaker.Besides, the optimized functional modules were integrated on a high strength aluminum alloy case-body.The service-life of the newly-designed vacuum circuit breaker, with significantly reduced number of parts, was tested.The results show that the optimized vacuum circuit breaker outperforms the conventional one because of a much longer service-life, a greater stability and a higher relliablity.We suggest that the novel vacuum circuit breaker be of much technological interest in industrial applications.