Extruded Sheet Metal Hole

Applications include for self tapping sheet metal screws or in thicker material to permit tapping for machine screws.

Extruded sheet metal hole.

An extruded hole is one that is generated at one station using a specially stepped punch that first shears a smaller hole and then follows through to deform the local area around the hole into a projection by limited forward extrusion. Alternately the hole could be pre pierced in a separate station and then the edges extruded at a second station. The following illustration shows the extruded hole geometry. It is recommended that the minimum distance between two extruded holes should be six times the thickness of sheet metal.

Tap fix screws for extruded holes in light gauge steel this article provides tap fix hole size recommendations for metals using light gauge punched extruded materials. Extruded holes unipunch tooling can be used to simultaneously punch a hole and extrude the material down. Extruded holes very close to the part edge can lead to sheet metal deformation or tearing. Creating an extruded hole using a punching process requires extreme pressure force.

You can imagine the shape as being a body to the punch of any shape and from this protrudes the punch pin of the diameter you want. Therefore the minimum distance between the extruded hole to edge if maintained.