Inertia friction welding counterweight disc with adjustable rotational inertia

The invention discloses a rotational inertia adjustable inertia friction welding counterweight disc, and provides an adjustable inertia disc device for an inertia friction welding machine, which comprises an inertia disc, a guide rail, a counterweight block, a ball screw, an inner ring and an outer ring. The inertia disc is not easy to disassemble due to overweight, so that the inertia disc serves as a fixed inertia disc; the guide rail is arranged on the inertia disc and is marked with accurate scales; the balancing weight is supported by the guide rail and serves as a main part for adjusting rotational inertia, and accurate movement and control of the position of the balancing weight are achieved through the ball screw. The outer ring is arranged at the outer ends of the balance weight disc and the guide rail and plays a role in protection, and the inner ring is installed on the balance weight disc and plays a role in supporting and protection. The guide rail, the balancing weight, the inner ring, the outer