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	s_T\|s_0,2, MPa	σ_U, 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
s_T\|s_0,2	Yield strength or limit of proportionality with a tolerance for residual deformation of 0.2%
σ_U	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.