Zinc-Aluminum Alloy Coated Tubing



Standard double roll welded tube is the base material of hot dipped zinc-aluminum alloy coated tubing. The tube surface is coated with one layer of zinc-aluminum alloy in order to provide a smooth finish and high corrosion resistance.

Technical Standard of Hot dipped Zinc-Aluminum Coated Tubing

Zinc coated tube can be made by adjusting the location of wind blades and the zinc coating cooling temperature. This coating layer has good plasticity and adhesive ability and the surface smoothness can reach the quality requirement of galvanized tube. The maximum coating layer can be 30μm which has good corrosion resistance.

The Zinc-aluminum alloy coated steel tubes contain about 5% Al, 95% Zn and little lanthanon in their coating layer. The Zinc-aluminum alloy coated steel tube is cooled down rapidly after galvanization, and the compact homo-crystals rich in zinc and aluminum are finely distributed. Zinc–aluminum coated steel tube rusts slower than regular zinc coated steel tubes because aluminum and zinc have similar electrochemistry properties.

Good plasticity and adhesion are the main advantages of Zinc-Aluminum coated steel tubing, so the corrosion resistance is unchanged before or after tube deformation. Its air corrosion resistance feature is two to three times better than regular zinc coated tube, and its very good adhesive ability maintains a stable combination between alloy layer and coated layer over time. The zinc-aluminum alloy coated tube has the best flexibility among all the hot dipped zinc tubes. The corrosion resistance and formability of the thicker zinc-aluminum alloy coated layer can be compared to a diffusion annealing zinc coated layer. It also has good welding capability. In conclusion, the zinc-aluminum coated layer has excellent features.

Inspection Technical Standard of Hot Dipped Zinc Coated Tubing

Inspection Technical Standard of Hot Dipped Zinc-Aluminum Alloy Coated Tubing