Lincoln Stick Electrode General Knowledge Facts

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Storing Low Hydrogen Electrodes:

Low hydrogen electrodes must be dry to perform properly. Unopened Lincoln hermetically sealed containers provide excellent protection in good storage conditions. Opened cans should be stored in a cabinet at 250º to 300ºF (120-150ºC).

1) Low hydrogen electrode coatings that have picked up moisture may result in hydrogen induced cracking, particularly in steels with 80,000 psi (550 MPa) and higher yield strength.

Moisture resistant electrodes with an "R" suffix have a high resistance to coating moisture pickup, and, if properly stored, will be less susceptible to this problem, regardless of the yield strength of the steel being welded. Specific code requirements may indicate exposure limits different from these guidelines.

All low hydrogen electrodes should be stored properly, even those with an "R" suffix. Standard E-xx18 electrodes should be supplied to welders twice per shift. Moisture resistant types may be exposed for up to 9 hours.

When containers are punctured or opened, low hydrogen electrodes may pick up moisture. Depending upon the amount of moisture, it will damage weld quality in the following ways:

2) A greater amount of moisture in low hydrogen electrodes may cause porosity. Detection of this condition requires x-ray inspection or destructive testing. If the base metal or weld metal exceeds 80,000 psi (550 MPa) yield strength, this moisture may contribute to underbead or weld cracking.

3) A relatively high amount of moisture in low hydrogen electrode causes visible external porosity in addition to internal porosity. It may also cause excessive slag fluidity, a rough weld surface, difficult slag removal, and cracking.

4) Severe moisture pickup can cause weld cracks in addition to underbead cracking, severe porosity, poor appearance and slag problems.

Re-drying Low Hydrogen Electrodes:

Re-drying, when done correctly, restores the electrodes' ability to deposit quality welds. Proper re-drying temperature depends upon the electrode type and its condition.

One hour at the listed final temperature is satisfactory. DO NOT dry electrodes at higher temperatures. Several hours at lower temperatures is not equivalent to using the specified requirements.

Electrodes of the E-8018 and higher strength classifications should be given no more than three 1-hour re-dries in the 700 to 800ºF (370 to 430ºC) range. This minimizes the possibility of oxidation of alloys in the coating, resulting in lower than normal tensile or impact properties.

Any low hydrogen electrode should be discarded if excessive re-drying causes the coating to become fragile and flake or break off while welding, or if there is a noticeable difference in handling or arc characteristics, such as insufficient arc force.

Electrodes to be re-dried should be removed from the can and spread out in the oven because:

1) Each electrode must reach the drying temperature.

2) The cardboard can liners char at about 350ºF (180ºC), damaging adjacent electrodes.

(1) Pre-dry for 1-2 hours. This will minimize the tendency for coating cracks or oxidation of the alloys in the coating.