Weldcote Metals Er90S-B3 Is Used To Weld Such Alloys As Z 1/4%Cr1%Mo Steels, Which Are Found In High Temperature And High-Pressure Piping And Vessels. May Also Be Used On Carbon Steels To Cr-Mo Steels But Should Always Have Careful Control Of Preheat, Inter-Pass And Post-Heat To Avoid Cracking. Use With A Pre-Heat And Inter-Pass Temperature Of 373 Degrees F Minimum. Some Typical Applications Are High Pressure Piping, Pressure Vessels, And Joining Dissimilar Combinations Of Cr-Mo And Carbon Steels.