HEAT-RESISTANT STEEL FOR PRODUCTION OF THE STEAM TURBINES ROTORS Russian patent published in 2006 - IPC C22C38/48 C22C38/54 C22C38/60 

FIELD: metallurgy; production of heat-resistant steel for rotors of steam turbines.

SUBSTANCE: the invention is pertaining to the field of metallurgy. in particular to the choice of composition of the heat-resistant steel. which may be used for manufacture of the rotors. arbors and other details of the steam turbines of high and medium pressure. The heat-resistant steel contains the components in the following ratio (in mass %): C - 0.11-0.20; Si - 0.03-0.1; Mn - 0.1-0.3; Cr - 9.0-12.0; Ni - 0 0.7; Mo - 0.9-1.6; V - 0.15-0.30; W - 0-2.0; Nb 0.02-0.06; B - 0-0.02; N - 0.005-0.05; Sn - 0-0.006; Sb - 0-0.005; As - 0-0.007; S - no more than 0.015; P - no more than 0.020; Fe - the rest. The contents of the components also is defined by ratios: 0.12≤C+N≤ 0.22; 0.9≤Mo+0.5W≤2.0; 0.15≤V+Nb≤0.3; Cr_eqv= %Cr+6(%Si) 44 (%Mo) +l. 5 (%W) +ll (%V) +5 (%Nb)-40 (%C)-30 (%N)-2 (%Mn)-4 (%Ni)> 6.5; P≤[0.l2-5(Sb+Sn)-As]/10; 10S≤ Mn ≤ 20S. The technical result of the invention is an increase of the steel resistance to the action of the supercritical temperatures of the steam, the durable strength, increased operational reliability and the service life of the turbine equipment.

EFFECT: the invention ensures an increased the steel resistance to the action of the supercritical temperatures of the steam, its durable strength, operational reliability and the service life of the turbine equipment.

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