The issue of replacing filler metal materials in welding procedure qualification
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The design uses Q345D pipes (with requirements of -20℃/34J). For the welding process evaluation of this steel, the electrode grade used is J507RH (E5015 N1 P type) with requirements of -40℃/57J. It is possible to use the J507 (E5015) (-30℃/57J) electrode for welding on site. The welding process evaluation is carried out in accordance with NB/T 47014; I believe that substitution is feasible. The main reasons for this are as follows: 1. In 47014, electrodes of types E5015 and E5015 N1 P are classified as FeT1-2 type electrodes, and their electrode group classification remains unchanged; therefore, they are suitable for welding Q345D (Fe1-2 type pipes), ensuring compatibility and weldability. 2. Additional provisions regarding the requirements for impact toughness in the change of welding electrodes in 47014: When a filler metal with lower requirements for passing the impact test is used in place of one with higher requirements, re-evaluation tests are necessary (unless the filler metal with lower requirements can still meet the specifications of this standard or the design documents) ； The low-temperature impact tests for J507 and J507RH require stricter test temperatures and absorbed energy values compared to Q345D pipes; therefore, I believe they can be used as substitutes. But some people simply reject us by saying that high base rates are not allowed, without giving any reason, which is really unfair.
J507RH (E5015 N1 P grade) (-40°C/57J): It is not possible to use J507 (E5015) (-30°C/57J) in field applications. J507RH requires retesting for diffused hydrogen, and the requirements are higher than those for J507; unless you conduct an additional impact strength test. The lower the temperature, the higher the requirements. Additionally, the price difference between the two welding materials is not significant, so it’s not worth saving that small amount of money
Low-generation high grades must be supported by welding procedure qualification.
Many specifications of L245N steel are similar to those of grade 20; can the evaluation applicable to grade 20 steel be used in place of that for L245N?
Sir, may I ask if there is any basis for this? If it can’t be replaced, I have to issue a corrective action order to someone else, and there needs to be a basis for that. I’ve checked over and over again but haven’t found any reason why it can’t be replaced. . .