Rebar upsetting process and rebar upset forging machine

A rebar upset forging machine, comprising:

• a machine frame provided with clamping dies, wherein the clamping dies form a clamping cavity that is configured to be opened and closed and is configured for holding rebar;
• an upsetting die mounted on the machine frame, wherein the upsetting die has an upsetting cavity with an enclosed cavity structure configured for upsetting and shaping an end of the rebar, and the upsetting die is configured as a solid die with a straight, closed radial cross-section that cannot be opened;
• and
• an upsetting power device provided on the machine frame,
• wherein centerlines of both the clamping cavity and the upsetting cavity align with each other, and one end of the clamping dies abuts against the upsetting die, and
• wherein the clamping dies are provided with a chamfer at the one end of the clamping dies abutting against the upsetting die.