I have a question regarding the heat treatment of WB36 boiler tubes

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There are steel pipes of type EN 10216-21 5NiCuMoNb 5-6-4 OD508*42, and the manufacturer uses a heat treatment process of normalizing (spray cooling) followed by tempering, with the aim of achieving higher mechanical properties; the resulting microstructure is bainite. According to EN 10216-2, the normalizing + tempering process should be used. I’m worried now that if the boiler factory welds these steel pipes without using spray cooling equipment after welding, the mechanical strength at the joints of the pipes will be significantly reduced as a result. (Because spray cooling was not used) I’m not sure if my concerns are unfounded. I looked into spray cooling; heat treatment using this method falls between normalizing and quenching. In other words, the cooling rate is faster than that in normalizing, but slower than that in quenching (using oil or water).