Punching is a low-cost and rapid process compared to drilling but with an inferior hole quality. This inferior hole quality is due to the die clearance which is necessary for the punching process. Punching mild steel requires a die clearance between 8 and 15% of the thickness. This means the hole will always be larger at the bottom than at the top. If the punch clearance is too small it will reduce the tool life dramatically and it will increase the punching pressure required. If the punch clearance is too big it will reduce hole quality. All Voortman angle lines can be equipped with multiple punches and dies which increases versatility and hole quality and reduces downtime.
The angle lines of Voortman are all equipped with high pressure hydraulics for maximum pressure and flow making the punching process extremely fast.
When the clearance is optimal the punch will penetrate the material about 1/3 of the thickness before fractures arise. These fractures at the upper and bottom side will align and join when the correct clearance is set.