The issue of heat retention in welding electrodes
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This post was last edited by Protein on 2010-4-28 at 14:06. During the installation process, E4303 (J422) welding rods were used; before use, these rods were heated to 150 degrees and dried for 1 hour! When in use, obtain 5KG from the insulated container ； By the time the welder uses 3KG of welding rod, it has already cooled down; the subsequent welding rods are at room temperature. What impact does this have on welding? Is it necessary for there to be a temperature?
The use of welding rods should be carried out in a heat-retaining container to maintain warmth. When in use, the welding rod cartridge cover must be on; if it loses its temperature, porosity defects are likely to occur during welding.
J422 is an acidic welding electrode, requiring a lower level of alkalinity compared to alkaline welding electrodes. Since the coating is prone to moisture absorption, which deteriorates the welding properties of the electrode, and hydrogen in water can cause pores and cracks in the weld, the electrode must be dried before use in order to reduce its hydrogen content. Drying is typically carried out at 350–450ºC for 1–2 hours. Keep it at 80-100°C for storage, and use it as needed.
There should be no problem with E4303. The main purpose of drying welding rods is to remove moisture from them, thereby preventing water vapor from affecting the weld pool during welding. Using them up on the same day will not have a significant impact on the weld quality. Most electrode drums come equipped with an external power supply for heat retention; it is advisable to connect the power supply for welding at critical joints, while this step can be omitted for less important joints.
The electrodes taken out must be placed in electrode holders that can retain heat, and the amount taken each time should be used up within 4 hours; otherwise, they must be returned to the electrode storage area and marked (electrodes that have been baked twice are considered unusable). A welder may take no more than two electrodes at a time from the holder, and it is not allowed to hold a bunch of electrodes in one’s hands. Those who violate the above requirements will have their welder’s card confiscated; they must drill three holes and then leave. The above are our requirements regarding electrode baking and usage. (I have confiscated the welding cards of several welders.)
J422 belongs to acidic welding electrodes and generally does not require drying. "By the time the welder uses 3KG of welding rod, it has already cooled down, and the subsequent welding rod is at room temperature – this has little impact on welding. Unless it is an environment with high air humidity, there is no need to take this too seriously.
There should be no problem with E4303; most electrode drums come equipped with a external power supply for heat retention. The power supply should be connected whenever possible, the drum should always be kept tightly covered, and a welder should not carry more than 2 electrodes at a time. If the area being welded is important, consider limiting the amount of electrodes a welder can take at each time.
I can say with certainty that after drying to remove the moisture, once it cools down, it still functions properly and is not affected in its use.
It’s okay if it cools down; what matters is avoiding moisture. The best way is to get three kilograms at once. This way, things from getting cold won’t happen
The electrodes that have been taken out must be placed in an electrode holder that can retain heat; this is a standard practice.
Based on my experience on site, it generally works once it cools down. Another issue is that when using it in structural applications, if it’s involved in critical structures, one needs to be extra careful