Factors Affecting Tool Wear

Clearance Proper clearance will yield longer tool life.
Hole Configuration Sharp corners will show wear much more quickly than straight or curved edges, particularly on punches. Narrow sections will wear faster than heavier sections.
Hole Size Small punches will wear faster than larger punches.
Lubrication A lubricant will increase tool life significantly.
Punching Conditions Reducing the hitting shock and holding the sheet flat allows the punch to cut clearly and will give better life to the punch.
Punch/Die Wear Punches will generally wear faster than dies. Dies are less affected by the factors described above than are punches.
Punching Speed High punching speeds can, under certain conditions, generate enough frictional heat to soften a punch. A softer punch will wear much faster.
Shear Face on Punch The portion of the punch that strikes first does most of the work and will wear faster.
Stripping Conditions Stripping the work piece from the punch evenly contributes to easy stripping.
Tool Material To develop toughness and hardness required for long life, high speed steel (HSS) undergoes several heat treatments.

The punches are double tempered to C62 Rockwell hardness. Hardened (59 Rockwell C) tool steel is the optimum material for dies. It correctly balances the need for maximum edge wear without breakage.

Turret Alignment

Mechanical damage of punches and dies is often misinterpreted as wear. Tight clearance on one side of a punch and die will accelerate wear at that point.

It is critical to regularly check turret alignment in order to prevent problems such as unacceptable part quality and turret wear.

Workpiece Properties Physical and mechanical properties of the work piece will greatly affect tool life.
Workpiece Thickness Thicker material will cause faster punch wear.