CHARACTERISTICS & APPLICATIONS
ífíl-77 is high iron oxide, iron powder electrodes characterized by low penetrating arc and dense slag, which completely covers the bead. Its covering contains substantial amounts of iron powder in combination with other ingredients. The coverings on these electrodes are very thick and usually amount to about 50% of the weight of the electrode. These electrodes are designed for fillet or groove welds in flat welding position with ac, dcep, or dcen, and will produce a flat or slightly concave weld face on fillet welds in horizontal position with either ac or dcen. These electrodes have a spray-type arc. They will operate at high travel speeds. Arc penetration is medium. Spatter loss is exceptionally low. These electrodes produce a heavy slag which is honeycombed on the underside. The slag is friable and easily removed. Welds produced with ífíl-77 have a flat to slightly concave weld face with a smooth, fine, even ripple, and good wetting along the sides of the joint. The weld metal may be slightly inferior in radiographic soundness to that from ícel-62 electrodes. High amperages can be used, since a considerable portion of the electrical energy passing through the electrode is used to melt the covering and the iron powder it contains. These electrodes are well suited for thicker base metal.
ífíl-77 have the same usability and design characteristics as ífíl-67 electrodes, except they are intended for use in situations requiring slightly higher tensile and yield strengths than are obtained with ífíl-67.
Storage and Drying Conditions: Hydrogen can have adverse effects on welds in some steels under certain conditions. One source of this hydrogen is moisture in the electrode coverings. For this reason, the proper storage, treatment, and handling of electrodes are necessary. Reconditioning of electrodes is recommended when they are damp.
Holding Ovens: 10°C-20°C above ambient temperature (50% max relative humidity). Drying Conditions: 135°C ± 15°C for 1 hour prior to use.
CHEMICAL COMPOSITION OF WELD METAL
| C | Mn | Si | P | S | Ni | Cr | Mo | V | Mn+Ni+Cr+Ni+V |
| 0.15 | 1.60 | 0.75 | 0.035 | 0.035 | 0.30 | 0.20 | 0.30 | 0.08 | 1.75 |
Single values are maxima, except where specified otherwise.
ALL-WELD-METAL MECHANICAL PROPERTIES
| Tensile Strength, MPa | Yield Strength, At 0.2% Offset, MPa | Elongation, % | Charpy V-Notch Impact at
-30°C, Joules |
| 490 | 400 | 22 | 27 |
Single values are minimal.
ELECTRODE SIZE & WELDING CURRENT
| Diameter, mm | Length, mm | AC, DCEN or DCEP, Amperes |
| 3.15, 3.20 | 450 | 125-185 |
| 4.00 | 450 | 160-240 |
| 5.00 | 450 | 210-300 |
WARNING: Safety and health information is available from many sources, including, but not limited to Safety and Health Fact Sheets listed in A11.3, ANSI Z49.1 Safety in Welding, Cutting, and Allied Processes published by the American Welding Society, 8669 Doral Blvd., Suite 130, Doral, FL 33166., and applicable federal and state regulations. The Safety and Health Fact Sheets are revised, and additional sheets added periodically.