Self-tapping screw
A self-tapping screw is a screw that can tap its own hole as it is driven into the material. For hard substrates such as metal or hard plastics, the self-tapping ability is often created by cutting a gap in the continuity of the thread on the screw, generating a flute and cutting edge similar to those on a tap. Thus, whereas a regular machine screw cannot tap its own ho901123le in a metal substrate, a self-tapping one can (within reasonable limits of substrate hardness and depth). For softer substrates such as wood or soft plastics, the self-tapping ability can come simply from a tip that tapers to a gimlet point (in which no flute is needed). Like the tip of a nail or gimlet, such a point forms the hole by displacement of the surrounding material rather than any chip-forming drilling/cutting/evacuating action.
SYSTEM | MATERIAL | Head Type | FINISH | SPECIFICATION |
METRIC SYSTEM |
Steel, Stainless Steel | Hex washer head, Pan, Truss, Flat, Pan framing |
ZP Nickel Black Dacromet Ruspert |
DIN7973, DIN7983, DIN7971, DIN7981, DIN7972, DIN7982 |
INCH SYSTEM |
ANSI/ASME B 18.6.4, ANSI/ASME B 18.6.3 |