10.028 Is an NR311 Ni Electrode E70 Equal to an E80?
|Q||I have a project where we are welding ASTM A913-Grade 65 I-sections to each other. Our specification calls for E80 electrodes for these welds, in conformance with AWS D1.1. The steel erector submitted a WPS for these welds using NR-311 Ni electrodes. The WPS listed these electrodes as E80, thus we approved the WPS. However, the label on the weld wire box out in the field lists this electrode as E70, as does Lincoln Electric’s literature on the electrode. When asked by the special inspector, the steel erector claimed that NR-311 Ni electrode is equal to an E80 even though it is technically listed as E70. They have submitted documentation, with Lincoln Electric letterhead, stating that the electrode is E70 but meets the requirements of E80.
We are trying to determine if the electrode they are using meets the specifications, which specifically call for E80 electrodes. We’re attempting to contact Lincoln Electric directly to get their opinion but we could use some outside advice, especially since the testing agency for the project seems reluctant to suggest anything and is looking to us for direction. Have you ever encountered a similar situation and if so how was it resolved? Please let me know what you would suggest.
— Structural Engineer from Oakland, CA.
|A||2/07 – Response prepared by Doug Williams, a consulting metallurgical and welding engineer with over 35 years of experience in metal working industries
Strictly speaking, “E80” is not explicity defined in any AWS document that I am aware of, although it clearly suggests an 80 ksi minimum UTS electrode. If the specification did not specify a consumable classification, then “matching” requirements for an ASTM A913, Grade 60 or 65 would be the classifications listed in AWS D1.1, Table 3.1, Group III. These do not all start with “E80”, although they are nominally 80 ksi minimum UTS. If the consumable manufacturer states in writing that the particular electrode meets the properties of an E8XTX-X classification, then the Engineer could accept it. I would not expect any inspector or test lab to accept a classification unless it is shown as such on the consumable manufacturer’s literature or it was approved by the Engineer.
2/07 – Response prepared by Dave Palfini, Principal, ASNT Level III, AWS SCWI, Testing Engineers, Inc., San Leandro
AWS A5.29-98 classifies the Lincoln NR-311 Ni electrode a E70T7-K2 indicating that it has a minimum tensile strength to 70,000 psi. To add value to his or her service, the special inspector should have researched the contractor’s claim that this electrode met the requirements of the specifications. The special inspector, or his or her support personnel at the inspection agency’s laboratory, should have gone to the Lincoln Electric Company’s website (www.lincolnelectric.com) and downloaded information for this electrode from the manufacturer’s catalog as well as the electrode’s Certificate of Conformance. Both of these documents indicate that the electrode meets the requirements of the specifications, 80,000 psi minimum tensile strength, as wells as FEMA 353 requirements. These documents then should have been forwarded to the EOR for review, and either approval or rejection.