Overview
A DIN 7981 self-tapping screw is a semicircular head screw with a sharp point and a slot. At one end of the rod there is a semicircular or countersunk head with a straight or cross slot (Philips, Pozidriv or Torx). On the opposite side there is a tip, which can be with a sharp end (shape C) or with a blunt end (shape F). If a semicircular head and blunt end self-tapping screw is used, it is necessary to mark and pre-drill a hole in the material before installing it. The diameter of the holes must exactly match the diameter of the metal product.
Fastening group DIN 7981
These screws are mainly made of stainless steel and belong to the stainless steel fastener group.
Materials of manufacture of DIN 7981 screws
DIN 7981 is available in a variety of materials:
1. Steel, which can be additionally coated:
- Zinc
- Black zinc
- Black zinc plating
2. Stainless steel A2 and acid-resistant steel A4. Thanks to the alloying elements that make up the steels, DIN 7981 screws are resistant to corrosion, external weathering, sudden temperature changes, and perform well in high humidity conditions, etc. A4 grade steel products can be used in structures that come into contact with certain aggressive environments: salt water, acids and alkaline solutions.
Areas of application of DIN 7981
DIN 7981 screws are universal fasteners. Their main application is fastening sheet metal or other types of steel materials to load-bearing metal and steel structures. The screws can also be used to fasten wooden, polyamide, and plasterboard structures to metal profile sheets.
Application - mechanical engineering, repair, internal installation work indoors, at any production facility. Due to their good technical characteristics, the scope of application of self-tapping screws is quite extensive. Self-tapping screws are widely used in many economic sectors: in various construction, repair and finishing processes, during the production, assembly and installation of furniture, installation of various hinged structures, in mechanical engineering, in everyday life, etc.
The scope of use also directly depends on the material of manufacture and the product's coating:
Galvanized steel is a good protection against corrosion if the fastener is to be used in an aggressive environment.
Stainless steel allows the fasteners to be used at significant temperature fluctuations and in aggressive and humid environments.
