Steel 12KH8VF (1Х8ВФ)

Designation

Name The value
Designation GOST Cyrillic 12Х8ВФ
Designation GOST Latin 12X8BF
Transliteration 12H8VF
By chemical elements 12Cr8WV
Name The value
Designation GOST Cyrillic 1Х8ВФ
Designation GOST Latin 1X8BF
Transliteration 1H8VF
By chemical elements 1Cr8WV

Description

12KH8VF steel is used: for the manufacture of pipes of furnaces; apparatus and communication refineries are continuously operating at temperatures up to +500 °C; tubes for plants of chemical and petrochemical plants with nominal pressure PN=19.6−98 MPa (200−1000 kgf/cm2); of billets intended for production of tubes of the cracking units of oil refining.

Note

Steel martensitic class.
Temperature intense scaling +650 °C.

Standards

Name Code Standards
Sheets and strips В23 GOST 103-2006
Bars and shapes В22 GOST 1133-71, GOST 2590-2006, GOST 2591-2006
Sheets and strips В33 GOST 4405-75
Steel pipes and fittings to them В62 GOST 550-75, TU 14-3-251-74, TU 14-3-457-76, TU 14-3-463-2005
Bars and shapes В32 GOST 7417-75, GOST 8559-75, GOST 8560-78, GOST 14955-77, GOST 20072-74, TU 14-11-245-88
Blanks. Of the workpiece. Slabs В31 TU 14-1-583-73

Chemical composition

Standard C S P Mn Cr Si Ni Fe Cu V Ti Mo W
GOST 20072-74 0.08-0.15 ≤0.025 ≤0.03 ≤0.5 7-8.5 ≤0.6 ≤0.6 Rest ≤0.2 0.3-0.5 ≤0.03 ≤0.2 0.6-1
TU 14-3-251-74 0.08-0.15 ≤0.025 ≤0.03 ≤0.5 7-8.5 ≤0.6 ≤0.6 Rest - 0.3-0.5 - - 0.6-1
Fe is the basis.
According to GOST 20072-74, when steel is scrap-process, the content of Cu ≤ 0.30%. When smelting steel by the method of electroslag remelting, the mass fraction of sulfur should not be more than 0.015%. The presence of molybdenum up to 0.20% and titanium up to 0.030% is allowed.
According to TU 14-1-583-73, the chemical composition is given for steel grade 12X8VF. In the finished rolled products, deviations in chemical composition are allowed in accordance with GOST 20072.

Mechanical properties

Section, mm sT|s0,2, MPa σU, MPa d5, % d10 y, % KCU, kJ/m2 HB, MPa
Rolled steel. Annealing at 840-860 °C, cooling with the furnace
≥165 ≥300 ≥22 - ≥50 ≥980 ≤217
Tubular billet on the other 14-1-583-73 after annealing
≥165 ≥390 ≥22 - ≥50 ≥981 ≤170
Seamless hot deformed tubes, heat-treated in the delivery condition according to GOST 550-75
≥167 ≥392 ≥22 - ≥50 ≥980 ≤170
Pipe kiln and communication in the delivery condition on the other 14-3-457-76 (impact strength is specified for tubes with wall thickness ≥ 12 mm and is determined for longitudinal samples)
≥216 ≥392 ≥22 ≥18 ≥50 ≥980 ≤170

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
d10 Elongation after rupture
y The relative narrowing
KCU Toughness
HB Brinell hardness number

Technological properties

Name The value
Macrostructure and pollution The macrostructure of billets, check for the etched cross templeto should not have shrinkage looseness, bubbles, delaminations, voids, cracks, inclusions and placenow visible without using the magnifying devices. The defects allowed on a point inhomogeneity, the Central porosity and segregation must not exceed 2 points (for each species), subcortical bubbles at 1 point at a depth of less than 2 mm.