| 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.
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| 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.
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