DetailsSeveral common methods such as rivets, screws, and spot welding are used to fasten materials to ductwork. Three types of screws are most often used. The first is self-tapping only and requires a hole to be drilled before the screw can be utilized. The others are both self-tapping but also create their own holes. Self piercing screws have very sharp points which act much like a scratch awl in making a small opening in the steel for the threads to engage and work the sheet metal into a coned threaded hole. These work well for light gage steel.Self-drilling screws have an integral drill point which creates a large hole for tapping. This allows the screws to be used on heavy gages of steel. The maximum total thickness of steel that the self-drilling screw can be used with is determined by the drill point.
- Conformance - Meets or exceeds IFI-113 (Revised: August 1, 2007) specifications for Type BSD screws
- Material - Cold heading quality steel wire
- Corrosion Resistance - Zinc plated
- Hardness - Case hardened to Rockwell C52 - 58
- Head Configuration - Hexagonal unslotted
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Weight 4 Pounds (Lb) Width 5 Inches (In) Height 4 Inches (In) Country of Origin TWN Length 4 Inches (In) Brand Duro Dyne