Only a few manufacturers have succeeded in establishing their own manufacturing of bi-metal screws. It is a special discipline that requires great technical know-how to master. The result, on the other hand, is products of the highest quality that, with superior performance, make an efficient difference and save time in a construction project.
A bi-metal screw is a combination of two different types of steel - hardenable steel and austenitic stainless steel. Stainless steel is corrosion-resistant and ductile, but soft and therefore unsuitable for self-drilling screws for steel substrates. The idea behind the bi-metal screw was to combine a drilling tip and the first few threads in hardenable steel with a screw in stainless steel. The invention of the bi-metal screw was a breakthrough in the fastening industry because it succeeded in combining the best properties from two different worlds in one screw: the strength of the hardenable steel and the corrosion resistance of the stainless steel.
This made it possible to manufacture self-drilling and self-tapping screws that are both corrosion-resistant and strong enough to drill into steel. In one efficient operation, the bi-metal screw thus provides the ideal combination of fast installation and corrosion resistance.
At RED HORSE, we have our own modern bi-metal manufacturing with a high degree of automation that ensures high manufacturing output and consistent quality. Manufacturing of bi-metal screws involves four essential processes:
Welding of the stainless part and steel part
Cold forging of the screw's drilling tip and thread
Hardening of the steel part, i.e. drilling tip and first few threads
Surface treatment
