The top punch of the press brake machine is specially heat treated within 3mm of the cutting edge, with high hardness, but it will wear out after a long time
Normal wear will blunt and round the tip.
If several punches are worn together, don’t worry temporarily. If a punch is partially worn, several punches should be machined together
Annealing, grinding and quenching.
It’s hard to do this job. You’d better not do it easily.