Abstract:Pearlite hardening has become an important factor endangering the safe operation of air separation plant. It will cause the valve or pipeline failure, increase the cooling loss of air separation, and even cause the safe operation of air separation tower, resulting in accidents. Combined with the pearlite hardening in the air separation tower of No.1 and No.4 oxygen generator in the workshop, the causes of pearlite hardening are analyzed, and the measures to prevent pearlite hardening from the aspects of design, operation and maintenance are put forward in this paper.