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1、 Definition of pearlitic heat-resistant steel It mainly contains Cr, Mo, V low alloy steel heat-resistant steel castings, such as ZG20CrMo, which can be used to manufacture cylinder, steam type, nozzle chamber and oil refining equipment of medium and high pressure steam turbine, with working temperature of 400 ~ 500 ℃; ZG20CrMoV, working temperature of about 500 ℃; ZG15Cr1Mo1V, working temperature of about 570 ℃.

2、 Heat treatment process of heat resistant steel Annealing or normalizing plus tempering, the working temperature is not more than 650 ℃, generally between 350 ~ 620 ℃.