Tesco Steel & Engineering manufactures ASTM A182 F5 alloy steel flanges — the 5% chromium, 0.5% molybdenum (5Cr-0.5Mo) chrome-moly forging grade. The chromium gives resistance to high-temperature sulphidic corrosion and oxidation while the molybdenum provides creep strength and temper resistance — making F5 a workhorse for elevated-temperature refinery and petrochemical service. As a hardenable alloy steel it normally needs preheat and post-weld heat treatment. Available in weld neck, slip-on, blind, socket-weld, threaded, lap-joint, spectacle and orifice types to ASTM A182 / ASME B16.5. Class 150 to 2500, NPS 1/2″ to 24″, PN6 to PN400. ISO 9001:2015 certified. Made in India.
ASTM A182 F5 (5Cr-0.5Mo) Alloy Steel Flanges
A182 F5 Weld Neck & Blind Flanges
Tesco Steel & Engineering manufactures A182 F5 flanges in all types from weld neck to orifice, Class 150 to 2500 — supplied annealed or normalized-and-tempered with EN 10204 3.1 / 3.2 certification, hardness results and third-party inspection on request. Explore the wider alloy steel flange range, the lower-chrome A182 F11 flanges and A182 F22 flanges, the higher-chrome A182 F9 flanges, and the flange dimension charts.
| ASTM A182 F5 flanges are available in the following specifications: | |
|---|---|
| Material Grade | ASTM A182 / A182M Grade F5 (5Cr-0.5Mo chromium-molybdenum alloy steel) |
| Alloy Type | Chromium-molybdenum (chrome-moly) hardenable alloy steel |
| Heat Condition | Annealed or normalized and tempered |
| Size | 1/2″ NB to 24″ NB (DN 15 to DN 600); larger to ASME B16.47 |
| Class / Rating | 150#, 300#, 600#, 900#, 1500#, 2500# · 3000#, 6000#, 9000# (socket-weld / threaded) |
| Pressure Ratings | PN 6 – PN 400 (PN6, 10, 16, 25, 40, 64, 100, 160, 250, 320, 400) |
| Related Specs | Pipe ASTM A335 P5; casting ASTM A217 C5; fittings ASTM A234 WP5; bolting A193 B5 |
| Dimensional Standards | ASME B16.5, ASME B16.47 (Series A & B), MSS SP-44, DIN EN 1092-1 |
| Flange Types | Weld Neck (WNRF), Slip-On (SORF), Blind, Socket Weld (SWRF), Lap Joint, Threaded / Screwed, Spectacle Blind, Long Weld Neck, Orifice, Plate |
| Flange Faces | Raised Face (RF), Flat Face (FF), Ring Type Joint (RTJ), Tongue & Groove (T&G) |
| Weld Filler | E502 / ER502 (matching 5Cr-0.5Mo), with preheat & PWHT |
| Testing | Hardness, hydrostatic, UT, MT/PT per spec; EN 10204 3.1 / 3.2 |
F5 is the 5Cr-0.5Mo member of the A182 chrome-moly family. The ~5% chromium drives its high-temperature oxidation and sulphidic-corrosion resistance, while ~0.5% molybdenum gives creep strength and resistance to temper embrittlement.
| Element | ASTM A182 F5 |
|---|---|
| Carbon (C) | 0.15% max |
| Manganese (Mn) | 0.30 – 0.60% |
| Silicon (Si) | 0.50% max |
| Chromium (Cr) | 4.0 – 6.0% |
| Molybdenum (Mo) | 0.44 – 0.65% |
| Phosphorus (P) | 0.030% max |
| Sulphur (S) | 0.030% max |
| Mechanical Property | ASTM A182 F5 |
|---|---|
| Tensile Strength (min) | 70 ksi (485 MPa) |
| Yield Strength (min) | 40 ksi (275 MPa) |
| Elongation (min) | ~20% |
| Hardness | ≤ 217 HBW (typical) |
| Service Temperature | Sustained high temperature, ~600–650°C |
| Condition | Annealed or normalized & tempered |
| Product Form | 5Cr-0.5Mo Designation |
|---|---|
| Forgings / Flanges | ASTM A182 F5 |
| Seamless Pipe | ASTM A335 P5 |
| Castings | ASTM A217 C5 |
| Fittings | ASTM A234 WP5 |
| Plate | ASTM A387 Gr 5 |
| Common name | 5Cr-0.5Mo Chrome-Moly Alloy Steel |
F5 Weld Neck Flange (WNRF)
F5 Slip-On Flange (SORF)
F5 Blind Flange
| Flange Type | Description & F5-Specific Use |
|---|---|
| Weld Neck (WNRF) | Tapered hub butt-welded to pipe for high-integrity, high-temperature refinery piping; weld with E502 filler, preheat & PWHT. |
| Slip-On (SORF) | Fillet-welded over the pipe; used in chrome-moly piping at moderate pressure. |
| Blind | Seals pipe ends and vessel nozzles in high-temperature hydrocarbon systems. |
| Socket Weld (SWRF) | Small-bore (1/2″–2″) instrument and branch connections in hot service. |
| Lap Joint (LJRF) | Used with an F5 stub end where frequent dismantling is required. |
| Threaded (TRFF) | Internal NPT/BSP threads for non-welded connections. |
| Spectacle Blind / Long Weld Neck | Isolation spades and nozzle/long-neck flanges in A182 F5 for high-temperature duty. |
| Property | F5 | F11 | F22 | F9 |
|---|---|---|---|---|
| Nominal type | 5Cr-0.5Mo | 1.25Cr-0.5Mo | 2.25Cr-1Mo | 9Cr-1Mo |
| Chromium | ~5% | ~1.25% | ~2.25% | ~9% |
| High-temp sulphidic resistance | High | Moderate | Good | Higher |
| Creep / temperature capability | High | Moderate | High | Higher |
| Typical role | Hot refinery sulphur service | Boiler / moderate temp | Hydrogen / high-temp | Hottest, highest-Cr service |
Molybdenum gives creep strength and temper resistance for sustained hot service to ~600–650°C.
5% chromium resists high-temperature sulphur (sulphidic) corrosion in refinery hydrocarbon streams.
Chrome-moly chemistry resists high-temperature hydrogen attack per the Nelson curves.
A long-established refinery and power material with matching pipe (A335 P5), fittings and bolting.
| Industry | Typical Application |
|---|---|
| Oil Refining | Crude and vacuum units, hydrocracker and hydrotreater hot piping flanges |
| Petrochemical | High-temperature hydrocarbon process flanged connections |
| Power Generation | Boiler, superheater and steam-line flanges |
| Hydrogen / Hydroprocessing | High-temperature hydrogen-service flanges per API 941 |
| Heaters & Furnaces | Fired-heater and transfer-line flanged connections |
| Catalytic Units | Hot reactor and regenerator piping flanges |
Made from certified 5Cr-0.5Mo with PMI verification of chromium and molybdenum — full chemistry and heat-treatment on the MTC.
Supplied annealed or normalized-and-tempered, with hardness within spec for weldability and service.
WNRF, SORF, blind, socket-weld, threaded, lap-joint, spectacle, LWN, orifice and plate — in RF, FF, RTJ and T&G.
EN 10204 3.1 / 3.2 MTC with hardness results, heat/lot traceability, hydrostatic and third-party inspection on request.
A182 F5 flange prices reflect the 5% chromium alloy content plus forging and heat treatment — it is a premium chrome-moly grade for high-temperature refinery service. Tesco Steel & Engineering offers competitive ex-works pricing from Mumbai with full export documentation and material traceability. Click Ask for Quote or message us on WhatsApp at +91 92233 66922 with flange type, size (NB), pressure class, quantity and documentation requirements.
Q1. What is an ASTM A182 F5 flange?
An ASTM A182 F5 flange is a forged chromium-molybdenum (chrome-moly) alloy steel flange with about 5% chromium and 0.5% molybdenum (5Cr-0.5Mo). The chromium gives resistance to high-temperature sulphidic corrosion and oxidation, while the molybdenum provides creep strength and temper resistance, making F5 a standard material for elevated-temperature refinery and petrochemical piping. Flanges are made to ASTM A182 and machined to ASME B16.5 / B16.47 dimensions.
Q2. What is the chemical composition of ASTM A182 F5?
ASTM A182 F5 nominal composition: carbon 0.15% max, manganese 0.30–0.60%, silicon 0.50% max, chromium 4.0–6.0%, molybdenum 0.44–0.65%, phosphorus 0.030% max, sulphur 0.030% max. The ~5% chromium with ~0.5% molybdenum is the defining 5Cr-0.5Mo chrome-moly composition.
Q3. What is F5 alloy steel used for?
ASTM A182 F5 is used for high-temperature, high-pressure service in oil refineries and petrochemical plants — crude and vacuum units, hydrocrackers, hydrotreaters and hot piping where resistance to high-temperature sulphur (sulphidic) corrosion and hydrogen is needed. The 5% chromium gives better high-temperature corrosion and oxidation resistance than lower-chrome grades like F11 and F22.
Q4. What is the difference between A182 F5, F9, F11 and F22?
These are chrome-moly alloy steels with increasing chromium for higher temperature and sulphidic-corrosion resistance: F11 is 1.25Cr-0.5Mo, F22 is 2.25Cr-1Mo, F5 is 5Cr-0.5Mo, and F9 is 9Cr-1Mo. F5's 5% chromium places it above F11 and F22 for high-temperature sulphur corrosion, while F9 (and F91) go higher still. Grade selection follows the service temperature and corrosivity.
Q5. Do A182 F5 flanges need post-weld heat treatment?
Yes, usually. As a hardenable chrome-moly alloy steel, F5 generally requires preheat (typically around 200–300 degrees C) before welding and post-weld heat treatment (PWHT, a temper around 700–760 degrees C) afterwards to relieve stress, temper the heat-affected zone and restore toughness. Matching low-hydrogen consumables (e.g. E502 / ER502) are used.
Q6. What standards apply to A182 F5 flanges?
A182 F5 flanges are forged to ASTM A182/A182M (Grade F5) and machined to ASME B16.5 (1/2 inch to 24 inch) or ASME B16.47 / MSS SP-44 for larger sizes, with EN 1092-1 for PN-rated flanges. Material is supplied annealed or normalized-and-tempered with EN 10204 3.1 / 3.2 certification. The matching cast grade is ASTM A217 C5; pipe is ASTM A335 P5.
Q7. What are the mechanical properties of A182 F5?
Typical ASTM A182 F5 properties: tensile strength 70 ksi (485 MPa) minimum, yield strength 40 ksi (275 MPa) minimum, elongation about 20% minimum, hardness generally below 217 HBW. It is supplied in the annealed or normalized-and-tempered condition with good elevated-temperature strength and creep resistance.
Q8. What temperature can A182 F5 flanges handle?
A182 F5 is used for sustained elevated-temperature service, commonly up to about 600–650 degrees C, with good creep strength and resistance to high-temperature sulphidic corrosion. The exact allowable temperature and pressure follow the applicable code (e.g. ASME B16.5 / B31.3) ratings for the grade.
Q9. What industries use A182 F5 flanges?
ASTM A182 F5 flanges are used in oil refining (crude, vacuum, hydrocracking and hydrotreating units), petrochemical processing, power generation (boiler and steam piping), and high-temperature process plant where chrome-moly creep strength and sulphidic-corrosion resistance are required.
Q10. Are A182 F5 flanges supplied with material test certificates?
Yes. Every A182 F5 flange is supplied with EN 10204 3.1 (or 3.2) mill test certificates confirming chemistry, mechanical properties, heat-treatment condition and heat/lot traceability, with hardness, hydrostatic testing and third-party inspection on request. Tesco Steel & Engineering is an ISO 9001:2015 certified manufacturer and exporter from Mumbai, India.