Electrode Selection

Table 7-2.—Electrode Selection Guide electric-arc welding. The first two digits in the symbol The fourth digit of the symbol represents special designate the minimum allowable tensile strength in characteristics of the electrode, such as weld quality, thousands of pounds per square inch of the deposited type of current, and amount of penetration. The numbers weld metal. For example, the 60-series electrodes have range from 0 through 8. Since the welding position is a minimum tensile strength of 60,000 pounds per square dependent on the manufacturer’s characteristics of the inch, while the 70-series electrodes have a strength of coating, the third and fourth numbers are often identified 70,000 pounds per square inch. together. The third digit of the symbol indicates the joint position for which the electrode is designed. Two num- Electrode Selection hers are used for this purpose: 1 and 2. Number 1 desig- nates an electrode that can be used for welding in any Several factors are critical when you choose an position. Number 2 represents an electrode restricted for electrode for welding. The welding position is particu- welding in the horizontal and flat positions only. larly significant. Table 7-2 shows the recommended 7-7