P91 steel (9Cr-1Mo-V-Nb-N) were developed from the midle of 1970s by the National Laboratory Oak Ridge (ORNL) under the auspices of the US government (US). P91 steel is widely used in industry such as in the pipeline requires high pressure and high temperature, or in the heat exchanger, boilers in thermal power plants. The reason, the heat goes out of the frame of a boiler superheater temperature resistance 570-600 ° C and pressures in the range 170-230 bar, in the final stages of overheating rigs, the pipeline will be subject to a working conditions are very harsh, and requested materials must have high mechanical properties, that are not destroyed by time and with high reliability creep resistance. Steel P(T) 91 were detected in different variants such as P92, P911 meets the above requirements, and will have a new foothold in the market in the coming years.
Keyword
welding of P91 steel, T91 steel, 9Cr-1Mo-V-Nb-N steel
