In NACE MR0175, can I qualify a fillet with a but weld coupon?

We have one WPS Qualified in butt joint and Hardness survey done according to NACE MR 0175 ( Figure 2) on Butt weld coupon.
Is it correct that we cannot use the above WPS in a fillet weld joint, because the fillet weld hardness survey is not carried out.


The applicability of weld procedure qualification tests for specifications is in accordance with the welding codes. For fillet welds, a hardness survey shall be in accordance with NACE MR0175/ISO 15156-2, Clause, Fig. 3. The use of butt weld hardness tests to qualify a fillet welding application is not specifically addressed in NACE MR0175/ISO 15156-2. The requirement of NACE MR0175/ISO 15156-2 is that the hardness values in the weld and heat affected zones remain in compliance. You may need a consultant to assist you in this determination.

Reference MP Inquiry 2017-11 (NACE MR0175 Part 2

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