Tubewell Steel & Engg. Co. is a leading manufacturer and stockist specializing in Alloy Steel Pipes, Tubes, Fittings and Flanges for critical industrial applications.

Alloy Steel Flanges

ASTM A182 F22 Flanges

2.25% Chromium – 1% Molybdenum forged flanges in Class 1 and Class 3 for high-temperature steam, boiler and hydroprocessing service.

ASTM A182 / ASME SA182 1/2" – 48" NB IBR Approved
2.25Cr-1Mo Grade

ASTM A182 F22 Alloy Steel Flanges

Tubewell Steel & Engg. Co. is a leading manufacturer, stockist and supplier of ASTM A182 F22 flanges in Mumbai, India. With 2.25% chromium and 1% molybdenum, F22 offers higher creep-rupture strength than F11 and is the preferred flange grade for A335 P22 main steam, boiler and hydrogen-service piping.

StandardASTM A182 / ASME SA182
GradeF22 Class 1 / Class 3
Size Range1/2" NB – 48" NB
Pressure Class150 – 2500 / PN6 – PN64

Product Overview

Higher creep strength for steam and hydrogen service

ASTM A182 F22 is a 2.25% chromium – 1% molybdenum ferritic alloy steel, widely regarded as the benchmark grade for elevated-temperature pressure parts. Its doubled molybdenum content gives significantly better creep and stress-rupture strength than F11, while the chromium level provides good resistance to oxidation and high-temperature hydrogen attack. Class 1 (415 MPa tensile, 170 HB max) suits applications needing lower hardness, and Class 3 (515 MPa tensile) is the standard grade for B16.5 flanges.

We supply F22 flanges forged from certified steel, annealed or normalized and tempered at a minimum of 675°C as A182 requires, then CNC machined to ASME B16.5, B16.47, MSS SP-44 or EN 1092-1. Bores are matched to the mating P22 pipe schedule and every flange is PMI-checked, hardness tested and hard-stamped with full heat traceability. IBR certification, EN 10204 3.1 / 3.2 documentation and third-party inspection are available on request.

  • Higher creep strength than F11
  • Service up to approx. 600°C
  • Resistant to high-temperature hydrogen attack
  • Class 1 & Class 3 strength levels
  • IBR approved supply for boiler piping
  • Matches A335 P22 & A234 WP22 systems

Specifications

Standard supply range for ASTM A182 F22 flanges

ParameterDetails
Material StandardASTM A182, ASME SA182
GradeF22 Class 1, F22 Class 3 (UNS K21590)
Dimension StandardASME B16.5 (1/2" – 24"), ASME B16.47 Series A & B (26" – 48"), MSS SP-44, EN 1092-1
Size1/2" NB to 48" NB (DN 15 – DN 1200)
Pressure ClassASME Class 150, 300, 600, 900, 1500, 2500
PN RatingPN6, PN10, PN16, PN25, PN40, PN64
Flange TypesWeld Neck, Slip-On, Blind, Socket Weld, Threaded, Lap Joint, RTJ, Long Weld Neck, Reducing, Orifice, Spectacle Blind
FacingRaised Face (RF), Flat Face (FF), Ring Type Joint (RTJ), Tongue & Groove, Male & Female
Face FinishSerrated 125 – 250 µin Ra (3.2 – 6.3 µm), smooth finish on request
Bore / ScheduleSCH 10 to SCH XXS, to match A335 P22 pipe
Heat TreatmentAnnealed or Normalized & Tempered (tempering min. 675°C / 1250°F)
B16.5 Material GroupGroup 1.10 (F22 Class 3)
TestingPMI, Hardness, Tensile, Impact, UT, MPI / DPT, Visual & Dimensional
CertificatesEN 10204 3.1 / 3.2, IBR Certification, NACE MR0175, TPI Reports

Material Grades & Equivalents

International equivalents of A182 F22

GradeASTM / ASMEUNSEN 10222-2W.Nr.JIS G3203Nominal
F22 Cl.1A182 F22 Cl.1K2159011CrMo9-101.7383SFVAF22A2.25Cr-1Mo
F22 Cl.3A182 F22 Cl.3K2159011CrMo9-101.7383SFVAF22B2.25Cr-1Mo

Equivalents are the nearest comparable grades for reference; confirm suitability against the governing design code before substitution.

Chemical Composition

Weight %, as per ASTM A182

CCarbon0.05–0.15
MnManganese0.30–0.60
PPhosphorus≤ 0.040
SSulphur≤ 0.040
SiSilicon≤ 0.50
CrChromium2.00–2.50
MoMolybdenum0.87–1.13
GradeCMnPSSiCrMo
F22 Class 10.05 – 0.150.30 – 0.600.040 max0.040 max0.50 max2.00 – 2.500.87 – 1.13
F22 Class 30.05 – 0.150.30 – 0.600.040 max0.040 max0.50 max2.00 – 2.500.87 – 1.13

Mechanical Properties

Minimum values at room temperature

GradeTensile StrengthYield Strength (0.2%)Elongation (in 2")Reduction of AreaHardness (HBW)
F22 Class 1415 MPa (60 ksi) min205 MPa (30 ksi) min20% min35% min170 max
F22 Class 3515 MPa (75 ksi) min310 MPa (45 ksi) min20% min30% min156 – 207
515MPa
Min. Tensile Strength (Cl.3)
310MPa
Min. Yield Strength (Cl.3)
20%
Min. Elongation

Physical Properties

Typical values (for reference)

PropertyMetricImperial
Density7.80 g/cm³0.282 lb/in³
Melting Range1450 – 1510 °C2640 – 2750 °F
Modulus of Elasticity210 GPa30.5 × 10³ ksi
Thermal Conductivity (100°C)36 W/m·K20.8 BTU/h·ft·°F
Mean Thermal Expansion (20–300°C)12.6 µm/m·°C7.0 µin/in·°F
Specific Heat0.46 J/g·°C0.11 BTU/lb·°F
Max. Service Temperature≈ 600 °C≈ 1110 °F

Dimension Chart

ASME B16.5 Class 300 weld neck flanges – dimensions in mm

Showing popular sizes. Class 150 and 600 – 2500 dimensions on request.
NPSFlange ODThicknessRF DiaBolt CircleBoltsHub Dia XHub Length Y
1/2"9512.734.966.74 × 1/2"3851
3/4"11514.342.982.64 × 5/8"4856
1"12515.950.888.94 × 5/8"5460
1 1/4"13517.563.598.44 × 5/8"6464
1 1/2"15519.173.0114.34 × 3/4"7067
2"16520.792.1127.08 × 5/8"8468
2 1/2"19023.9104.8149.28 × 3/4"10075
3"21027.0127.0168.38 × 3/4"11778
4"25530.2157.2200.08 × 3/4"14684
5"28033.4185.7235.08 × 3/4"17897
6"32035.0215.9269.912 × 3/4"20697
8"38039.7269.9330.212 × 7/8"260110
10"44546.1323.8387.416 × 1"321116
12"52049.3381.0450.816 × 1 1/8"375129
14"58552.4412.8514.420 × 1 1/8"425141
16"65055.6469.9571.520 × 1 1/4"483144
18"71058.8533.4628.624 × 1 1/4"533157
20"77562.0584.2685.824 × 1 1/4"587160
24"91568.3692.2812.824 × 1 1/2"702167

Thickness = minimum flange thickness excluding 2 mm (0.06") raised face. Hub Dia X = hub diameter at base, Hub Length Y = length through hub of weld neck flange. All dimensions in mm.

Applications

Where ASTM A182 F22 flanges are used

Power Plants

Main steam and hot reheat piping in sub-critical thermal units.

Boilers & HRSG

Superheater headers and HRSG high-pressure steam connections.

Hydroprocessing

Hydrocracker and hydrotreater reactor piping in hydrogen service.

Refineries

Reformer, coker and high-temperature process lines.

Pressure Vessels

Nozzle and manway flanges on high-temperature reactors.

Fertilizer Plants

Ammonia synthesis loops with hot hydrogen and nitrogen.

Testing & Why Choose Us

Quality you can verify on every heat

Ready Stock

Large inventory for fast dispatch

Certified Material

MTC EN 10204 3.1 / 3.2

100% PMI

Positive material identification

On-time Delivery

Pan-India & export shipping

Visual & Dimensional PMI Test Hardness Test Tensile Test Impact Test Ultrasonic Test MPI / DP Test Macro / Micro Test

Frequently Asked Questions

Quick answers about A182 F22 flanges

Both share the same 2.25Cr-1Mo chemistry. Class 1 is heat treated for lower strength (415 MPa tensile, 205 MPa yield, 170 HB max), while Class 3 provides 515 MPa tensile and 310 MPa yield. Class 3 is the grade normally used for ASME B16.5 flange pressure ratings.

F22 has roughly double the molybdenum of F11, which gives higher creep-rupture strength at temperatures above about 540°C. It is chosen for main steam, reheat and hydrogen service where F11 allowable stresses become limiting.

Yes. F22 is widely used in hydroprocessing units per API 941 guidance. We can supply flanges with controlled hardness, impact testing and step-cooling or other supplementary requirements as specified by the project.

F22 is a P-No. 5A material. Preheat of about 200°C and post-weld heat treatment in the range of roughly 700–760°C are commonly specified by ASME B31.1 / B31.3, depending on wall thickness.

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