Tesco Steel & Engineering forges ASTM A182 F22 slip on flanges — the 2¼% chromium, 1% molybdenumalloy steel that is the heavy-duty creep and hydrogen-service rung of the chrome-moly ladder — to ASME B16.5 Class 150–2500 from ½″ to 24″ NB, larger patterns to order. The classic grade of main steam and hot reheat lines and of hydrocracker and hydrotreater loops per API RP 941 — picking up where F11 stops. Supplied as F22 Class 3 (Cl.1 on request), heat treated per ASTM A182, faced SORF (flat face or RTJ where specified), alongside the complete family F5, F9, F11 and F91. Every lot with EN 10204 3.1/3.2 MTC. ISO 9001:2015, made in Mumbai, India — exported to 50+ countries.
ASTM A182 F22 Alloy Steel Flanges — In Stock at Our Mumbai Works
What is an ASTM A182 F22 Slip On Flange?
F22 = the heavy-duty rung.ASTM A182 F22 is a 2¼Cr-1Mo alloy steel forging grade: roughly double the chromium and molybdenum of F11, buying more creep strength at steam temperatures and a higher standing on the API RP 941 hydrogen-attack curves. As a slip-on, it installs with two fillet welds under chrome-moly discipline — preheat, B3 consumables, PWHT. It is the classic grade of main steam, hot reheat and hydrocracker piping.
Also searched as: F22 slip on flange, F22 Cl.3 slip on flange, 2.25Cr slip on flange, SA182 F22 slip on flange, 10CrMo9-10 slip on flange, 1.7380 slip on flange — all refer to the product on this page.
Creep-strength-enhanced — modern high-energy steam
Rule of thumb: power plants climb the ladder for creep strength (temperature), refineries climb it for corrosion (sulfur). F22 is the heavy-strength rung — and the classic hydroprocessing grade on the API RP 941 Nelson curves.
ASTM A182 F22 Chemical Composition
C
Mn
Si
P
S
Cr
Mo
0.05-0.15
0.30-0.60
0.50 max
0.040 max
0.040 max
2.00-2.50
0.87-1.13
Values in weight % per ASTM A182 — Classes 1 and 3 share this chemistry; the class difference is heat treatment and strength. Against F11 this is roughly double the chromium and double the molybdenum: more carbide-stabilising power against hot hydrogen, more creep strength at steam temperatures.
ASTM A182 F22 Cl.3 Mechanical Properties
Tensile Strength, MPa (ksi)
Yield Strength, Min, MPa (ksi)
Elongation % min (2")
Reduction of Area % min
Hardness, HB
515 (75) min
310 (45) min
20
30
156-207
Class 3 — normalized & tempered or quenched & tempered — is the class flange orders receive by default. The annealed Class 1 (415 MPa min tensile, 205 MPa yield) is forged where the specification calls for it. Values are demonstrated per heat on the EN 10204 certificate.
A182 F22 Slip On Flange Specifications
ASTM A182 F22 Slip On Flanges are available in the following specifications:
Material
ASTM A182 F22 Class 3 (default) / ASME SA182 F22 Cl.3 (UNS K21590); Cl.1 on request
Size
1/2"NB to 24"NB per ASME B16.5; larger patterns to order
Class
150#, 300#, 400#, 600#, 900#, 1500#, 2500#
Facing
Raised Face (SORF) — default; Flat Face or RTJ where the piping class specifies
Heat Treatment
Normalized & tempered or quenched & tempered (Cl.3); annealed (Cl.1) — per ASTM A182, thermal record retained
Service
Steam & hot hydrogen duty — rated to 649 °C in the ASME B16.5 tables, creep governing in the upper range
Installation
Two fillet welds (hub + bore), pipe set back 1/8"; preheat + E9018-B3 consumables + PWHT ~700-750 °C per B31.3
Finish
Bare (anti-rust oiled); other surface preparation on request
Certification
EN 10204 3.1 (standard) / 3.2 witnessed
Equivalent Grades of ASTM A182 F22
Standard
ASME
UNS
Werkstoff Nr.
DIN / EN (working equivalent)
ASTM A182 F22
SA182 F22
K21590
1.7380
10CrMo9-10 (formerly 10CrMo910)
European grades are duty equivalents rather than chemistry-identical matches — certificates always state the actual grade and class forged. System partners: ASTM A335 P22 pipe and A234 WP22 fittings — the 2¼Cr trio specified together on steam and hydroprocessing lines.
Why A182 F22 Slip Ons Are Specified
Creep Strength Past F11
Doubled chromium and molybdenum carry allowable stresses usefully beyond F11's ~550-560 °C practice — the grade of main steam and hot reheat in a generation of plants.
The Hydroprocessing Classic
Hydrocracker reactors and heavy hydrotreater loops are built in 2¼Cr-1Mo — F22 stands high on the API RP 941 Nelson curves where F11 runs out.
Forgiving for Its Class
Proven over decades, weldable with standard B3 practice, tolerant of the real world in ways the high-performance F91 is not — discipline required, but not perfection.
Slip-On Fit-Up Economy
Where the piping class permits, the slip-on saves the weld-neck's bevel-matching and cut-length precision — welcome on alloy lines where every rework costs PWHT.
Know the Handoffs
Milder duty: F11. Hottest modern headers: F91. Hot sulfidic streams: F5/F9. Critical RT-mandated lines: F22 weld necks.
How Our A182 F22 Slip On Flanges Are Manufactured
1
Forging — cut billet of certified A182 F22 heat is hot-forged into the flange blank, keeping full heat traceability from raw material to despatch.
2
Heat treatment — normalized & tempered or quenched & tempered per ASTM A182 (Class 3), with the thermal record retained per lot; the controlled temper delivers the 156-207 HB working condition.
3
Machining — hub, faces and bolt holes to ASME B16.5; the bore machined slightly over pipe OD per the slip-on tolerance.
4
Facing — SORF raised face with serrated stock finish; flat face or RTJ groove where the order specifies.
5
Testing & marking — mechanical, chemical and hardness verification against the heat, then permanent marking of grade, class, size, rating and heat number.
6
Certification & packing — EN 10204 3.1 MTC (3.2 witnessed on request), export-packed as pictured on this page.
Where A182 F22 Slip On Flanges Are Used
The upper creep range and heavy hydrogen duty: main steam and hot reheat piping, superheater outlet headers, hydrocracker and heavy hydrotreater loops per API RP 941, ammonia converter circuits, and hot-wall reactor nozzle connections. Our alloy steel production and packing below:
Example: “Slip On Flange, 6″ NB, ASME B16.5 Class 300, RF, ASTM A182 F22 Cl.3, EN 10204 3.1 — 20 pcs.” Quotations normally within 24 hours with price, unit weight and delivery.
ASTM A182 F22 Slip On Flanges — Frequently Asked Questions
What is an ASTM A182 F22 slip on flange?
It is a slip-on flange forged from ASTM A182 F22 — a 2¼% chromium, 1% molybdenum alloy steel — dimensioned to ASME B16.5. The flange slides over the pipe end and is secured with two fillet welds, and the chemistry is the heavy-duty rung of the chrome-moly ladder: more creep strength than F11 and higher standing on the hydrogen-attack curves. It is the classic grade of main steam lines, hot reheat piping and hydrocracker loops.
What is the chemical composition of ASTM A182 F22?
Per ASTM A182 (Classes 1 and 3 share the chemistry): carbon 0.05-0.15%, manganese 0.30-0.60%, silicon 0.50% max, phosphorus 0.040% max, sulphur 0.040% max, chromium 2.00-2.50% and molybdenum 0.87-1.13%. Against F11 that is roughly double the chromium and double the molybdenum — more carbide-stabilising power against hot hydrogen and more creep strength at steam temperatures.
What are the mechanical properties of A182 F22 slip on flanges?
For F22 Class 3, the class normally supplied for flanges, per ASTM A182: tensile strength 515 MPa (75 ksi) minimum, yield strength 310 MPa (45 ksi) minimum, elongation 20% minimum in 2", reduction of area 30% minimum, and hardness 156-207 HB. The grade is supplied heat treated (normalized and tempered or quenched and tempered), and the values are demonstrated per heat on the EN 10204 certificate.
What is the difference between F22 Class 1 and Class 3?
Heat treatment and strength — the chemistry is identical. Class 1 is supplied annealed at 415 MPa (60 ksi) minimum tensile and 205 MPa yield, the softer, maximum-ductility condition. Class 3 is normalized and tempered (or quenched and tempered) to 515 MPa (75 ksi) tensile and 310 MPa yield, and is what flange orders receive unless Class 1 is stated. Piping specifications almost always call for Class 3; state the class explicitly where it matters.
When is F22 chosen over F11?
When temperature or hydrogen pushes past F11's comfort zone. Typical practice runs F11 to roughly 550-560 °C metal temperature in steam service; F22's doubled chromium and molybdenum carry creep strength usefully beyond that, and its higher standing on the API RP 941 Nelson curves covers hotter, higher-partial-pressure hydrogen — which is why hydrocracker and heavy hydrotreater loops are classically 2¼Cr-1Mo. The piping specification fixes the boundary; both grades come from the same forge here.
What is the difference between A182 F22 and F91?
F91 is the creep-strength-enhanced modern grade — 9Cr-1Mo micro-alloyed with vanadium, niobium and nitrogen — with allowable stresses far above F22 at the same temperature, letting high-energy steam plants use thinner, lighter piping. The price is metallurgical discipline: F91 demands tightly controlled welding, PWHT and hardness windows, and small errors cost creep life. F22 is the forgiving, proven workhorse; F91 the high-performance specialist. The design code and project specification make the choice.
What temperature can A182 F22 slip on flanges handle?
ASME B16.5 rates the 2¼Cr material class to 649 °C, with creep governing the allowable stresses in the upper range. In working practice F22 picks up where F11 stops — roughly 550-560 °C — and carries steam and hydrogen duty toward 600 °C, with F91 taking the hottest modern headers. As with every flange, the pressure rating falls as temperature rises — check the B16.5 table for the class at design temperature.
Why is F22 used in hydrogen service?
Because it stands high on the API RP 941 Nelson curves. Hot, high-pressure hydrogen attacks steel by diffusing in and reacting with carbides to form internal methane fissures (HTHA); chromium and molybdenum stabilise the carbides against it. With 2¼% Cr and 1% Mo, F22 covers hydrogen conditions that would destroy carbon steel and out-run F11 — which is why hydrocracker reactors, heavy hydrotreater loops and ammonia converter piping are classically built in 2¼Cr-1Mo.
How is an A182 F22 slip on flange welded to pipe?
With two fillet welds — hub outside, bore inside, pipe set back 1/8" (3 mm) from the face — under chrome-moly discipline: preheat (typically 150-200 °C), matching E9018-B3 / ER90S-B3 consumables, and post-weld heat treatment at about 700-750 °C per ASME B31.3 requirements. F22 is air-hardening; plan the preheat and PWHT into fabrication, and hold low-hydrogen practice throughout.
What is the equivalent of ASTM A182 F22 in other standards?
ASME SA182 F22 is the boiler-code twin and UNS K21590 the designation number. The European working equivalent is 10CrMo9-10 (Werkstoff 1.7380, formerly DIN 10CrMo910). System partners specified alongside it: ASTM A335 P22 pipe and A234 WP22 fittings — the 2¼Cr trio of steam and hydroprocessing lines. Certificates always state the actual grade and class forged.
Are slip on flanges allowed in high-temperature service?
Within limits. Slip-on flanges are permitted by ASME B31.3 and serve on lower-criticality hot lines, but many power and refinery piping classes restrict creep-range and cyclic services to weld neck flanges, whose full-penetration butt weld can be radiographed and resists thermal fatigue better than fillet welds. Follow the piping class: where it allows a slip-on, an F22 slip-on delivers the metallurgy at lower flange and fit-up cost.
Is A182 F22 a stainless steel?
No. With 2-2.5% chromium, F22 is a low-alloy steel — far below the roughly 10.5% chromium needed to passivate. It rusts in ambient wet service like any carbon steel and offers no answer to aqueous corrosion; its alloying is aimed at creep strength and hydrogen resistance at elevated temperature. For wet corrosion move to 300-series stainless; for hot sulfidic refinery streams, to the higher-chromium F5 and F9.
What sizes and classes are A182 F22 slip on flanges available in?
From ½" to 24" NB per ASME B16.5 in Classes 150 through 2500, with larger patterns forged to order. Chrome-moly material is project-specific rather than shelf stock, so flanges are typically forged against the order — standard sizes normally dispatch within a few weeks with EN 10204 3.1 certification. State the required delivery on the enquiry and we confirm the schedule with the quotation.
What details are needed to get an accurate A182 F22 slip on flange quotation?
Five elements plus commercial terms: (1) size and standard — e.g. 6" NB ASME B16.5; (2) pressure class — 150 through 2500; (3) facing — SORF (raised face) default, flat face or RTJ where specified; (4) grade and class — ASTM A182 F22 Cl.3 (default) or Cl.1 where the specification requires, with any supplementary requirements; (5) certification — EN 10204 3.1 or 3.2. No pipe schedule is needed for the slip-on bore. Add the quantity and destination and we return price, weight and delivery.
Who manufactures ASTM A182 F22 slip on flanges in India?
Tesco Steel & Engineering is an ISO 9001:2015 certified flange manufacturer based in Mumbai, India, forging ASTM A182 F22 slip on flanges from ½" to 24" NB per ASME B16.5 — alongside the full chrome-moly family F5, F9, F11 and F91 — with heat-treated supply, full heat traceability and EN 10204 3.1/3.2 certification on every lot. Flanges are marked with grade, size, class and heat number and export to more than 50 countries.
