Experimental Study on Process Optimization of Heat Treatment of TP90H-9Cr Casings for ThermalRecovery Wellfor in-situ Combustion Super Heavy Oil

Analyzed in the essay are the chemical composition characteristics and technique requirements of the steel types of casings for thermal recovery well for in-situ combustion super heavy oil.10Cr9Mo1VNb steel normally used on power plant boiler is used as a substitution steel type for casings for thermal recovery well for in-situ combustion super heavy oil，with it’s original heat treatment process being optimized.The research shows that the TP90H-9Cr casing which is tempered right after hot-rolling is satisfactory to the application requirements in terms of elevated-temperature strength，oxidation resistance and CO₂ corrosion resistance.Although the microstructure of a TP90H-9Cr casing under room temperature is inherited from that of the as-rolled pipe to a certain extent，the desirable performance indexes are able to be obtained by means of solution strengthening and precipitation strengthening of alloy elements.