E7018 the right way and why

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This is data sheet on using Low Hydrogen rod and why you need to per heat the rodDave From https://www.materialwelding.com/what...ing-procedure/Storage of Low Hydrogen Stick ElectrodesLow hydrogen stick electrodes must be dry to perform properly. Unopened hermetically sealed containers provide excellent protection in good storage conditions. Opened cans should be stored in a cabinet at 250 to 300°F (120 to 150°C). Low hydrogen stick electrode coatings that have picked up moisture may result in hydrogen induced cracking, particularly in steels with a yield strength of 80,000 psi (550 MPa) and higher.Moisture resistant electrodes with an “R” suffix in their AWS classification have a high resistance to moisture pickup coating and, if properly stored, will be less susceptible to this problem, regardless of the yield strength of the steel being welded. All low hydrogen stick electrodes should be stored properly, even those with an “R” suffix. Standard EXX18 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:1. 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 under-bead or weld cracking.2. A relatively high amount of moisture in low hydrogen electrodes causes visible external porosity in addition to internal porosity. It also may cause excessive slag fluidity, a rough weld surface, difficult slag removal, and cracking.3. Severe moisture pickup can cause weld cracks in addition to under-bead cracking, severe porosity, poor appearance, and slag problems.How many times baking of a low hydrogen electrode is allowed?This is the most common question that arises with many welding engineers/ QA-QC personnel. While the Codes and electrodes specifications are silent on this query, precautions must be taken care not to bake electrodes more than twice. The obvious reason is ‘Each baking sequence will remove the essential moisture required in the coating and additive substances which hold the coating strong on the core wire of the electrode. To be precise, any low hydrogen electrode should be discarded if excessive redrying 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.Welding consumable storage and handled guidelines should be in accordance with the consumable manufacturer’s instructions and guidelines and as given in the AWS A5.XX series of filler metal specifications. To reduce exposure to moisture, certain welding consumables should be stored in warm holding ovens after they have been removed from the manufacturer’s packaging. Low-hydrogen SMAW electrodes supplied in non-hermetically sealed containers should be baked according to manufacturer’s instructions prior to useLast edited by smithdoor; 4 Hours Ago at 11:05 PM.HF 170 welderHF 4x6 band sawSouth Bend 9NMillB&D mag drillVictor torch