Dual-mass flywheel arc spring is the product that our company has been developing all the time. Our company began to develop arc spring in 2012. Through experimental verification, arc spring can be directly produced by upgraded equipment program. The arc and angle of spring are controlled by equipment. No physical deformation of spring is needed after forming, so that spring materials and materials can be reduced in the process of forced bending forming. The damage of spring ensures the life of spring.