Alloy 36NKH (ЭП713)

Designation

Name The value
Designation GOST Cyrillic 36НХ
Designation GOST Latin 36HX
Transliteration 36NH
By chemical elements 36NiCr
Name The value
Designation GOST Cyrillic ЭП713
Designation GOST Latin EP713
Transliteration EhP713
By chemical elements -

Description

Alloy 36NKH used: for the production of billets ragged, made the free forging on presses or RCM and intended for the manufacture of tubes; manufacture of structures and pipelines operating at low temperatures.

Standards

Name Code Standards
Classification, nomenclature and General rules В30 GOST 10994-74
Blanks. Of the workpiece. Slabs В31 TU 14-1-2526-78, TU 14-1-2543-78
Bars and shapes В32 TU 14-11-245-88

Chemical composition

Standard C S P Mn Cr Si Ni Fe Cu
TU 14-1-2526-78 ≤0.05 ≤0.02 ≤0.02 0.3-0.6 0.4-0.6 ≤0.3 35-37 Rest ≤0.25
GOST 10994-74 ≤0.05 ≤0.015 ≤0.015 0.3-0.6 0.4-0.6 ≤0.3 35-37 Rest ≤0.25
Fe is the basis.
According to GOST 10994-74 the chemical composition is presented for the 36NX alloy (EP713).
TU 14-1-2526-78 chemical composition is presented for the alloy grade 36NH-SH (EP713-SH). In the finished metal, deviations are allowed for the content of manganese and chromium - (minus) 0.10% for each element.

Mechanical properties

Section, mm sT|s0,2, MPa σU, MPa d5, %
Tubular billet on the other 14-1-2526-78. Heating to 850-900 °C (exposure for 15 minutes), air cooling or furnace (longitudinal samples)
20-25 ≥196 ≥390 ≥38

Description mechanical marks

Name Description
sT|s0,2 Yield strength or limit of proportionality with a tolerance for residual deformation of 0.2%
σU Limit short-term strength
d5 Elongation after rupture

Technological properties

Name The value
Pressure treatment Clan and the ratio of the extrusion billet according to TU 14-1-2526-78 should be not less than 2.8 in terms of the sizes of the cross sections of the ingot and workpiece.
Macrostructure and pollution In the macrostructure of the workpiece in the state of delivery should be free of cracks, gas bubbles, subcortical bubbles, Samorodov crust, delamination, traces of shrinkage and slag inclusions visible to the naked eye. The degree of development of the Central porosity, point heterogeneity and phase separation of the square in points should not exceed 1 score. The alloy is checked on the contamination of non-metallic inclusions. The norm of non-metallic inclusions by the maximum score should not exceed: - oxides, stroke is 1.5; the oxides of point - 2,0; - silicates fragile - 1.5, and - silicates plastic - 1,5; the non - deformed silicates - 1,5; - sulphides - 1,0; - nitrides and carbonitrides and 3.0.
Temperature coefficient of linear expansion According to GOST 10994-74 CTE (1.0 to 2.0)·10-6 deg-1 in the temperature range 20÷100 °C and from plus 20 to minus 258 °C. On the other 14-1-2526-78 CTE (0,6-2,2)·10-6 deg-1 in the temperature range 20÷100 °C.