Development of the zinc coating pipe connection technology with arc soldering method using

The application of the arc brazing method for zinc-coated pipes joining with using the copper-based additives is suggested in this publication. This method is an alternative of the arc welding with minimal destruction of coating at the adjacent to the weld area, and it application has been analyzed and substantiated. The microstructure and microhardness research of the zinc-coated low-carbon steel pipes with the diameter of 150 mm and wall thickness of 3.2 mm was made and research results are presented. The research results have shown that joint formation takes place due to a diffusive layer at the alloy line, and the connection strength depends on its sizes. It is revealed that magnification of the intermetallic phases volume concentration in the weld metal increases its strength. It is found that the strength of the arc-welded pipe joints is affected by bevel edges. The connection with bevel edges has a greater strength with straight edges, as well as the contact area is increased with the base metal weld.   The arc brazing method can be recommended for zinc-coated pipes joining with using the CuAl8 wire and the bevel edge has to be made before arc brazing via research results. This method will provide the sufficient joints strength without the considerable zinc cover damage.