|Designation GOST Cyrillic||20Х5МЛ|
|Designation GOST Latin||20X5ML|
|By chemical elements||20Cr5Mo|
20KH5ML steel is used: for the manufacture of the 1st, 2nd and 3rd groups casting parts of valves of oil refining units operating at temperatures of the working medium from -40 to +650 °C without restriction of the nominal working pressure; furnace doubles, pump casings and other components operating in hot oil environments containing sulfur compounds under pressure at temperatures up to +550 °C; casting parts of valves and actuators to it; for the manufacture of pipes tsentrobezhnolityh for the manufacture of coils of tubular furnaces in the production of ammonia, hydrogen, ethylene, carbon disulphide, etc., operating in the temperature range 760−1060 °C and a pressure of 3.92 MPa (40 kgf/cm2).
Stainless steel in hot oil environments containing sulfur compounds, heat-resistant martensitic class. Heat resistance to +600 °C.
|Castings with special properties (iron and steel)||В83||GOST 2176-77|
|Steel castings||В82||GOST 977-88, OST 26-07-402-83, TU 26-02-19-75, TU 4112-091-00220302-2006, ST ЦКБА 014-2004|
|Steel pipes and fittings to them||В62||TU 1333-047-00220302-02|
According to GOST 977-88 molybdenum can be replaced by titanium in an amount of no more than 0.10%, provided that the parts are operated at a temperature of no more than 425 ° С.
According to GOST 2176-77 the chemical composition is given for steel grade 20Х5МЛ. Deviations from the norms of chemical composition are allowed: for carbon ± 0.020%; for silicon ± 0.10%; on manganese, copper, chromium and nickel ± 0.10% each; by titanium and tungsten ± 0.050% each; by vanadium, molybdenum and niobium ± 0.020% each.
|Section, mm||sT|s0,2, MPa||σU, MPa||d||y, %||KCU, kJ/m2|
|The castings are supplied according to GOST 2176-77|
Description mechanical marks
|sT|s0,2||Yield strength or limit of proportionality with a tolerance for residual deformation of 0.2%|
|σU||Limit short-term strength|
|d||Elongation after rupture|
|y||The relative narrowing|