Five Grades of Zinc

Posted by Li Li over 6 months ago

When the steel enters the kettle at 840 to 850 degrees Fahrenheit, zinc-iron alloy layers start to form. This portion normally represents about 50 to 70 percent of the total coating thickness, with the zinc being the top layer. Directly coming out of the kettle, all galvanize steel track profiles (http://www.adtomall.com/galvanize-steel-track-profiles-with-the-best-price) are extremely bright, despite the coating appearance. --------- Five grades of zinc for continuous hot-dip galvanizing: -- 1. London Metal Exchange (LME) Grade- contains a minimum of 99.995% zinc -- 2. Special High Grade (SHG)- high purity of zinc containing a minimum of 99.990% of zinc -- 3. High Grade (HG)- contains a minimum of 99.95% zinc -- 4. Intermediate Grade (IG)- contains a minimum of 99.5%zinc -- 5. Prime Western Grade (PWG)- contains 0.5 to 1.4% lead, and a minimum of 98.5% zinc