Click your industry to see where hex flange self tapping screws are used.
What is a hex flange self tapping screw?
A hex flange self tapping screw is a tapping screw with a hexagonal head that has an integral flange under it, acting as a built-in washer. It cuts or forms its own thread in sheet metal, aluminium and plastic as it is driven in, so the mating part needs only a pilot hole and no tapping. The flange spreads the clamping load over a wider area, which means one part replaces a separate screw and washer.
Which standard does it follow, DIN or ISO?
The thread, point and head follow the hexagon head tapping screw standard ISO 1479 / DIN 7976, with the thread form to ISO 1478 (ST thread) and the mechanical properties of heat-treated steel screws to ISO 2702. The integral flange is a head modification that DIN 7976 does not itself cover, so the flange form is made to standard industry proportions or to your drawing. Send us your specification with your enquiry.
What is the sharp point, and do I need a pilot hole?
The sharp (cone) point is the Type C point of ISO 1479 / DIN 7976. It starts easily and aligns the screw in thin sheet metal. Yes, in steel and most metals you still need a pilot hole, drilled slightly smaller than the screw core diameter, because the screw forms its own thread rather than drilling. The right size depends on the sheet thickness and material, so test on a sample before production. If you want a screw that drills its own hole, you need a self drilling screw instead.
What is the advantage of a hex flange over a plain hex head tapping screw?
The flange takes the place of a separate washer. It spreads the load, protects the surface of the sheet and reduces the chance of the head pulling through thin material, and it removes one part from assembly. The hex head also takes a socket or nut driver, so you can apply much more driving torque than with a Phillips recess.
What is the difference between a self tapping and a self drilling screw?
A self tapping screw forms a thread in a hole that already exists, so you need to drill a pilot hole first. A self drilling screw has a drill point that makes its own hole and then forms the thread, in one operation. Use self tapping screws where holes are already punched or drilled, as in most sheet metal fabrication, and self drilling screws where you want to fix straight through the material.
Should I choose steel or stainless steel 304?
Zinc plated steel is the standard choice for general sheet metal work indoors. Its case-hardened surface, to ISO 2702, lets it form threads in steel sheet reliably. Stainless steel 304 resists rust and staining, so choose it for visible, humid or washdown applications. It cannot be case-hardened like carbon steel, so it works best in thin sheet, aluminium and plastic, or in pre-drilled holes, and should be driven at moderate speed.
Can you make custom sizes?
Yes. Besides the sizes we supply regularly, we can manufacture hex flange self tapping screws in custom sizes to your RFQ, in steel and stainless steel 304. Send us the thread size (ST), length, material, finish, quantity and a drawing or sample, and we will quote.
Where can I buy hex flange self tapping screws in Bangalore?
Excel Trading Corporation supplies hex flange self tapping screws with a sharp point, in zinc plated steel and stainless steel 304, from our Kumbarpet office in Bengaluru to customers in Karnataka and across India. Call +91 7204435253 or email info@exceltrading.in with your size and quantity.
