Is heat treatment required again after repair or welding repairs?

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Both NB/T 47015 and GB/T150 specify that for Fe-1 and Fe-III, if the repair thickness is 13 mm or less, no further heat treatment is required. Question: 1. The standard specifies the depth of repair, but does it not set any specific requirements regarding the length of repair? 2. NB/T 47015 states that minor patch welding does not require further heat treatment. How is this ‘minor area’ determined? Does it refer to the entire cross-section of the material? 3. The standard does not specify that external pre-welded gussets be welded after heat treatment; perhaps this is a sensitive issue. Can it be understood that, except for repairs and small-area patch welding, all other types of welding require additional heat treatment? Furthermore, can some pre-welded components be considered as cases of small-area patch welding? I’d like to ask everyone! Thank you!