Bolt fastening structure of pipe die

The invention discloses a bolt fastening structure of a pipe die. The bolt fastening structure of the pipe die comprises a mounting hole arranged in an upper die, a screw hole arranged in a lower die and a bolt which is inserted in the mounting hole and can be in threaded connection with the screw hole, and is characterized in that an outer spring clamp is arranged on the bolt, an inner spring clamp is arranged in the mounting hole, a spring is sleeved on the bolt between the outer spring clamp and the inner spring clamp, and a bolt end socket is arranged at the mounting hole; when opening a mold, no damage can be caused to screw threads during the form removal; and during the die assembly, the upper die and the lower die are aligned and a bolt is screwed on, the operation is convenient, and assembling efficiency is high.