ASTM A182: Forged & Rolled Alloy and Stainless Steel Flanges, Fittings & Valve Parts

Reviewed by the Crestflo Engineering Team

ASTM A182/A182M is the ASTM International standard specification covering forged or rolled alloy- and stainless-steel pipe flanges, forged fittings, and valves and parts for high-temperature service. It sets out chemical composition, mechanical properties and heat treatment, so a flange, forged fitting or valve body comes with a known metallurgy and a known strength. The current edition is A182/A182M-23; the "M" companion gives values in SI units. Every grade carries an "F" prefix. F316, for example, is the forging grade of 316 stainless. The same specification, adopted into the ASME Boiler & Pressure Vessel Code (Section II, Part A), goes by SA-182, and its requirements match those of A182.

The full standard sits behind ASTM International's paywall, since they hold the copyright and sell it directly. What you'll find on this page is a summary: the specification, its grades, and how it connects to neighboring codes, all aimed at helping you specify correctly. We don't host the ASTM PDF here.

Also Known As: A182M, SA-182, A182/A182M & Grade "F" Designations

ASTM A182 shows up under several names in practice. You'll see it as A 182, "A182", ASTM A182/A182M (the dual inch-pound/metric designation), and A182M (the metric companion on its own). ASME pressure-vessel work carries the same requirements under a different label, SA-182 / SA-182M, which means "SA-182 F316" and "A182 F316" point to the same material. Grades tend to get cited by their "F" designation paired with a UNS number: F304 (S30400), F316 (S31600), F51 (S31803), F53 (S32750), F44 (S31254), and others follow the same pattern. A companion standard, ASTM A961/A961M, spells out the requirements shared by forged flanges, fittings, and valves supplied to A182.

What ASTM A182 Covers: Product Forms & Scope

A182 covers pressure-boundary parts that are forged or rolled, not cast, and not built up through wrought or welded fabrication, for use in high-temperature service.

• Pipe flanges, weld-neck, slip-on, blind, socket-weld and threaded patterns.
• Forged fittings, elbows, tees, crosses, couplings, unions, caps and reducing inserts.
• Valves and valve parts, forged bodies, bonnets and other pressure-containing components.
• End preparations typically include socket-weld, threaded (NPT), butt-weld and flanged ends.

Scope disambiguation (important): ASTM A182 specifies forged parts. It's not the same as ASTM A403 (wrought seamless/welded austenitic fittings), ASTM A105 (carbon-steel forgings), or ASTM A479 (bar for valves and vessels). The grade prefix "F" denotes a forging grade; the ASME twin is SA-182. High-nickel alloys such as Inconel, Monel and Hastelloy aren't A182 grades at all. Those forgings fall under ASTM B564.

ASTM A182 Grade Classes & Grades: F304, F316, F51, F53, F44 (with UNS Numbers)

A182 covers five metallurgical families. This HTML grade map lets you match an "F" grade to its UNS number, trade name, and the Crestflo material page for that alloy. Designations follow the applicable standard, so check the current edition for your project before relying on them.

Crestflo covers A182 austenitic, super-austenitic and duplex/super-duplex F-grades in its US instrumentation range. The low-alloy Cr-Mo steels (F11/F12/F22/F91/F92) fall outside that scope, and so do the martensitic grades (F6a). Nickel alloys aren't A182 grades either. Inconel, Monel and Hastelloy forgings get specified under ASTM B564 instead, and Crestflo can supply them under that correct spec.

ASTM A182 Chemical Composition & Mechanical Properties (F304L, F316L, F51, F53)

A182 caps the maximum and minimum values by grade, and the figures below reflect published limits typical of the austenitic and duplex grades that matter to Crestflo. These numbers follow the applicable standard and can be tailored to what's needed. Check the current standard for the full ranges.

Austenitic F-grades come solution-annealed and quenched. Duplex and super-duplex grades get solution-annealed and rapidly quenched instead, which keeps the austenite-to-ferrite balance where it needs to be and preserves corrosion resistance. A182 also calls for heat/lot marking, so every part can be traced back to its heat of steel.

ASTM A182 vs A403, A105, A479 & A312: How the Specs Differ

A182 is one of several product-form specifications an instrumentation specifier will run into. Same alloy, but a different manufacturing route and a different product form.

A182 versus A403 trips people up more than anything else. A182 covers forged flanges, fittings and valve parts. A403 covers wrought austenitic fittings. Yes, the alloys overlap in plenty of cases. But the forming method is different, and so are the parts each spec actually describes.

Standards, Compliance Overlays & Proof: NACE, ASME B16.34, MTC Traceability

A182 sets the base metallurgy. Project specs then layer additional requirements on top of the grade.

• Sour service: NACE MR0175 / ISO 15156 set hardness and metallurgical limits (ISO 15156) for wet H₂S environments, on top of the A182 grade.
• Valve pressure, temperature ratings: a forged A182 valve body is rated to ASME B16.34, and where specified, to API valve standards as well. It isn't rated to a fitting standard. Crestflo instrumentation valves are qualified against ASME B16.34 / API, while compression tube fittings follow ASTM F1387 instead.
• CRA/duplex forging qualification: where required, NORSOK M-650 qualifies the manufacturer for duplex and super-austenitic forgings.
• Traceability: every part ships with an EN 10204 MTC 3.1 (3.2 on request) and a heat/lot number marked right on the part, backed by PMI, in-house NDT, and destructive testing at ISO/IEC 17025-accredited labs. See traceability and testing & inspection. Crestflo holds ISO 9001 / 14001 / 45001 & PED certification, though these are stated on content pages rather than numbered.

Forged A182 Instrumentation Parts from Crestflo: Flanges, Fittings & Valve Bodies

Crestflo makes forged instrumentation components to ASTM A182, available in stainless, duplex, super-duplex and super-austenitic grades:

Standard items ship from ready stock. Specials are made to order, and delivery typically runs 6–8 weeks. Material is of Indian origin, though US and European melt is available on request, and it's fully traceable; see US-origin compliance for details. Small MOQ and private-label options are both available.

Request a forged A182 part: Request a quote or request a sample. Not sure which A182 F-grade matches your alloy call-out? Ask our engineering team for your cross-reference right on the RFQ, and Crestflo will sort it out.

Why Crestflo for ASTM A182 Forged Parts

Crestflo is the instrumentation division of a four-decade-old export house recognized by the Government of India, with a delivery track record across the Middle East. That heritage stands behind a new manufacturing brand. For an A182 specifier, this means a grade offering that's scoped correctly (the alloys we actually supply, stated plainly), EN 10204 MTC 3.1/3.2 with a heat number on every part, PMI, NDT and ISO/IEC 17025-lab destructive testing, and drop-in dimensional interchange for the majors. We Engineer Confidence, backed by the proof a QA engineer needs before accepting the part. Learn more at why Crestflo.

Frequently Asked Questions About ASTM A182

Related Standards & Materials

• ASTM A479, bar for valves & vessels
• ASTM A276, stainless bar & shapes
• ASTM A312, austenitic stainless pipe
• ASTM A213, instrumentation & heat-exchanger tubing
• ASME B16.34, valve pressure–temperature ratings
• NACE MR0175, sour-service metallurgy
• EN 10204, material test certificates
• 316 / 316L · Duplex 2205 · 254 SMO
• All instrumentation standards