What Is ASTM A182 F630?

ASTM A182/A182M-26a is the current listed edition for forged or rolled alloy and stainless steel flanges, forged fittings, valves and similar pressure-system parts. Grade F630 identifies the ordered material grade; it does not define the flange dimensions, pressure class or facing.

For ASME-pattern flanges, ASME B16.5-2025 covers pressure-temperature ratings, dimensions, tolerances, marking, testing and joint-related requirements for the sizes and classes within its scope. ASTM A182 and ASME B16.5 answer different procurement questions: one primarily defines the forged material/product requirements; the other defines the flange dimensional and rating system.

ASTM A182 versus ASME SA-182

ASTM publishes A182/A182M. ASME adopts material specifications for Boiler and Pressure Vessel Code use under an “SA” designation. Buyers should state the governing code, exact designation and edition because an ASTM and ASME adoption should not be assumed interchangeable without checking the applicable code edition, permitted materials and project requirements.

What is 17-4 PH equivalent to?

17-4 PH is commonly cross-referenced as Type 630, UNS S17400 and EN 1.4542. These identifiers describe a related alloy family, but they are not automatic substitutes for an ASTM A182 F630 flange. Product form, heat treatment, mechanical requirements, dimensions, examination, marking and certification still have to satisfy the ordered specification.

Why Heat Treatment Must Be Stated

17-4 PH develops its property balance through solution treatment followed by precipitation hardening, also called aging. The Carpenter Technology Custom 630 datasheet explains that the aging temperature and time determine the resulting properties. Condition A is the solution-treated starting condition; the final aged condition must be chosen for the service and order requirements.

The table summarizes process direction from the alloy producer’s published guidance. Acceptance values must come from the ordered ASTM/ASME edition and the actual heat or lot documentation, not from a general website table.

H900 vs H1150: Which Should a Buyer Choose?

Start with the design requirement, not the condition name. H900 may be considered where higher strength and hardness are needed. H1150 may be considered where a lower-strength but tougher and more ductile condition is preferred. The correct decision depends on pressure-temperature design, external loads, bolting and gasket loads, corrosion mechanism, stress-corrosion risk, impact or toughness requirements, weld procedure, machining sequence and applicable code.

A flange quotation should not silently substitute one condition for another. If the RFQ omits the condition, the supplier should request clarification before final technical acceptance.

Is 17-4 PH Magnetic?

17-4 PH is generally magnetic because the normal solution-treated and aged microstructure is predominantly martensitic. Magnetic response is not an acceptance test for grade identity or heat-treatment condition. Verify material through traceability, marking, the MTC and any ordered PMI or laboratory test.

What Does “Class 600 F630 Flange” Mean?

F630 identifies the material grade, while Class 600 identifies a pressure class under the applicable flange standard. Class is not a fixed pressure in every service: the allowable rating depends on the standard, material group and temperature. The order must also state NPS, flange type, facing, bore or pipe schedule, dimensional edition and any project-specific requirements.

ASTM A182 F630 Flange RFQ Checklist

1. Material specification: ASTM A182/A182M or ASME SA-182, exact edition, Grade F630 and UNS S17400 where required.
2. Final condition: H900, H925, H1025, H1075, H1100, H1150, H1150M or another approved condition; do not write only “heat treated.”
3. Flange definition: weld neck, slip-on, blind, socket weld, threaded or other approved type; RF, FF or RTJ facing as applicable.
4. Dimensions and rating: governing standard and edition, NPS/DN, class or PN, bore or pipe schedule and any drawing-controlled dimensions.
5. Service data: design pressure and temperature, medium, corrosion concerns, cyclic loads and mating equipment.
6. Examination and evidence: MTC type, heat treatment record, mechanical test results, hardness, PMI, NDE, dimensional report, marking and third-party inspection when required.
7. Commercial data: quantity, packing, destination and document-language requirements.

Frequently Asked Questions

What ASTM grade is duplex 2205 equivalent to?

This is a different material question: duplex 2205 forged flanges are commonly ordered under ASTM A182 Grade F51 or F60 depending on the specified UNS grade and requirements. Duplex 2205 is not equivalent to F630/17-4 PH.

What is the ASTM standard for flanges?

There is no single ASTM standard for every flange. ASTM specifications commonly define material/product requirements, while ASME B16.5 or another dimensional standard may define dimensions and ratings. The material, flange type, size range and governing code determine the correct combination.

What is the difference between 17-4 PH H900 and H1150?

They use different aging temperatures and produce different property balances. H900 is generally on the higher-strength/hardness side; H1150 generally provides lower strength with greater ductility and toughness. Project requirements and certified results govern.

Is H1150M the same as H1150?

No. H1150M is a two-stage modified overaging treatment used for a different processing and property objective. It should be stated and certified separately.

Can a supplier choose the heat-treatment condition?

The final condition should be agreed from the design and purchase requirements. A supplier can review the RFQ and raise technical questions, but should not silently choose or substitute a condition.