Metal self-tapping screws

Metal self-tapping screws are most commonly made of stainless and high-carbon steel, brass.

To improve installation and performance properties, the fastener is zinc-plated, chrome-plated or nickel-plated.

The range of metal self-tapping screws is wide. Classification is based on several features:

• head shape – flat, round, hexagon;
• drive configuration – slot, cross recess, hex socket, anti-vandal, torx;
• length and shank diameter of the self-tapping screw;
• presence of a press washer;
• thread pitch and presence of a drill point at the tip of the shank.

Self-tapping screws with a drill point have two cutting edges, which make the fastener easier to drive in. Unlike fasteners with a sharp or blunt point, these do not require pre-drilled holes. However, they are not recommended for joining dissimilar materials – they are better suited for connecting metal elements.

Self-tapping screws made of stainless or alloy steel are used where welding is not an option when assembling metal structures and a bolted connection is not possible. The fastener is selected based on the intended operating conditions of the structure being joined.