Damping cutter bar for turning coarse-pitch threads

The invention discloses a damping cutter bar for turning coarse-pitch threads, and relates to the field of turning. The damping cutter bar comprises a cutter bar body and a sealing base, wherein the cutter bar body is made of 40Cr so as to have enough strength and hardness; a cutter head mounting groove is formed in the front end of the cutter bar body, and a fastening nut used for locking a blade is arranged at the upper end of the cutter head mounting groove; a cylindrical horizontal through hole is formed in the cutter bar body; a step-shaped check block, a butterfly-shaped damping spring, a rubber damping block, another butterfly-shaped damping spring and a metal sliding block are sequentially arranged in the cylindrical horizontal through hole from a cutter head to the sealing base; and the rear end of the horizontal through hole is connected with the sealing base. Vibration generated during turning is reduced through the combined action of the butterfly-shaped damping springs, the damping block and damp