The High-Temperature Trinity: A Comparative Metallurgical and Engineering Analysis of 12Cr1MoV, ASTM A335 Grade P11, and EN 16Mo3 Creep-Resisting Alloy Steel Pipe The modern power generation and petrochemical industries operate under immense thermal and mechanical duress, relying on specialized metallic materials capable of sustaining structural integrity and predictable mechanical performance over protracted periods at temperatures