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.

For the tapped screw hole this is typically made using a male punch that creates the hole and extrudes the metal. The following illustration shows the extruded hole geometry. It is always better to specify hole diameters that are greater than the sheet s thickness t. Extrusions our commonly used to accept sheet metal screws or permit tapping into a deeper distance than just the material thickness.

Alternately the hole could be pre pierced in a separate station and then the edges extruded at a second station. By the way i can only punch the extruded screw hole the other feature i need with a very. This procedure creates in effect the. Design for manufacturability sheet metal guidelines bends for the ease of manufacturing multiple bends on the same plane should occur in the same direction.

Extruded holes very close to the part edge can lead to sheet metal deformation or tearing. Avoid large sheet metal parts with small bent flanges. Creating an extruded hole using a punching process requires extreme pressure force. A pre punched hole is required as a one hit pierce and extrude gives poor hole quality and has limited adjustment on the machine.

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. 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. 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. In a sheet metal design specifying hole sizes locations and their alignment is critical.

It is recommended that the minimum distance between two extruded holes should be six times the thickness of sheet metal. Therefore the minimum distance between the extruded hole to edge if maintained.