Extruded Sheet Metal Hole

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.

Extruded sheet metal hole.

It is recommended that the minimum distance between two extruded holes should be six times the thickness of sheet metal. Minimum hole diameter the diameter of the hole in sheet metal part should not be very small small holes are created by piercing operation and for manufacture small holes small sizes punches are required. Avoid large sheet metal parts with small bent flanges. It is always better to specify hole diameters that are greater than the sheet s thickness t.

This procedure creates in effect the. Creating an extruded hole using a punching process requires extreme pressure force. Die buttons with oversized internal diameters typically with a 020 radius instead of a cutting edge are used to permit the material to flow downward and punch an extruded hole. For the tapped screw hole this is typically made using a male punch that creates the hole and extrudes the metal.

Applications include for self tapping sheet metal screws or in thicker material to permit tapping for machine screws. In low carbon steel sheet metal the minimum radius of a bend should be one half the material thickness or 0 80 mm. Alternately the hole could be pre pierced in a separate station and then the edges extruded at a second station. 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 very close to the part edge can lead to sheet metal deformation or tearing. Therefore the minimum distance between the extruded hole to edge if maintained. Design for manufacturability sheet metal guidelines bends for the ease of manufacturing multiple bends on the same plane should occur in the same direction. The following illustration shows the extruded hole geometry.

In a sheet metal design specifying hole sizes locations and their alignment is critical. Extrusions our commonly used to accept sheet metal screws or permit tapping into a deeper distance than just the material thickness.