1. MANUFACTURERS OF A DIVERSE RANGE OF ADVANCED WELDING CONSUMABLES SECTION 10 NSB-312 FOR JOINING DIFFICULT TO WELD HIGH CARBON STEELS AND DISSIMILAR METAL COMBINATION WHEN NO EXACT SPECIFICATION OF THE BASE METAL EXISTS DATA SHEET NO. 148 SPECIFICATION AWS A5.4 BS EN 1600 JIS Z 3221 CLASSIFICATION E312-16 E 29 9 R D312-16 PRODUCT DESCRIPTION A metallurgically based rutile flux with balanced additions of chemically basic and amphoteric minerals that deposits duplex weld metal containing some 40% delta ferrite and 60% austenite. The flux is extruded onto a fully alloyed 29Cr 9Ni core wire using a blend of silicates that ensures both coating strength and resistance to subsequent moisture absorption. WELDING FEATURES OF THE ELECTRODE This unique flux formulation ensures excellent arc stability, ease of initial arc strike and re-strike, minimal spatter on AC and virtually none on DC+. The resultant weld seams are smooth, evenly rippled and free from undercut while slag detachability is excellent. Metal recovery is some 103% with respect to core wire weight. APPLICATIONS AND MATERIALS TO BE WELDED Primarily designed for high carbon steels, cast or wrought, which are well known as difficult to weld or problem steels. The duplex microstructure of the weld metal will tolerate high dilution with such steels while still maintaining its strength ductility and thus resistance to cracking. It can also be used very successfully for joining carbon steels to stainless steels, the only exception to its extensive use on such applications is that at service temperatures above 300 º C a drop in weld metal ductility occurs. WELD METAL ANALYSIS COMPOSITION % BY Wt. C Mn Si S P Cr Ni Mo Cu Fe MIN - 0.5 - - - 28 8.0 - - MAX 0.15 2.5 1.0 0.03 0.04 32 10.5 0.75 0.75 TYPICAL 0.10 0.9 0.8 0.01 0.02 29 9.5 0.05 0.03 Bal. WELD METAL PROPERTIES (ALL WELD METAL) PROPERTY UNITS MINIMUM TYPICAL OTHERS Tensile strength N/mm 2 660 820 0.2% Proof stress N/mm 2 - 640 Elongation on 4d % 22 23 HV 260 Reduction of Area (RA) % - 30 WELDING AMPERAGE AC or DC+ ∅ (mm) 2.0 2.6 3.2 4.0 5.0 MIN 20 50 70 100 130 MAX 50 80 110 150 210 OTHER DATA Electrodes that have become damp should be re-dried at 120 o C for 30 mins. RELATED PRODUCTS Please contact our Technical Department for detail. WI-0304 DS148 NSB-312, Rev. 1, Date 02.01.2009