Guides / Specifications

Forging Certifications and Specs Explained: What to Ask Your Supplier

October 11, 2026

Certifications and specs are where forging buyers lose the most time, because the names sound similar and the requirements are easy to state wrong on an RFQ. This guide covers the ones that come up most often in forging, what each one actually covers, and when it is worth requiring.

Quality management system certifications

These cover how a supplier runs its business, not any one part or material.

ISO 9001 is the base quality management standard. It says the supplier has documented processes, tracks nonconformances, and is audited against that system on a regular cycle. Most established forge shops hold it. Treat it as a baseline for a serious supplier, not a differentiator.

IATF 16949 is the automotive industry’s quality standard, built on top of ISO 9001 with extra requirements around production part approval, statistical process control and supplier development. If your part is going into a vehicle program, especially for an OEM or tier one, this is often a contractual requirement, not optional.

AS9100 is the aerospace equivalent, adding configuration management, risk management and traceability requirements suited to flight critical parts. Aerospace primes generally will not place orders without it, and it is a reasonable filter even for aerospace-adjacent parts that are not flight critical.

None of these certify a specific part. They certify the system the supplier uses to make every part, which is why a certificate number is worth checking rather than taking on faith. Certification bodies publish registries, and a quick search of the supplier’s name against the certifying body confirms the certificate is current and covers the right site, since a company with three plants may hold certification at only one of them.

Process and product specs

These apply to a specific part, material or process, layered on top of whatever quality system the supplier holds.

API 6A and API 20B cover forgings for wellhead and Christmas tree equipment and open die forgings for the oil and gas industry, specifying material, testing and documentation requirements for pressure containing parts. If your part is going into a wellhead assembly, the spec, not just a general “oil and gas experience” claim, is what to ask for.

PED (Pressure Equipment Directive) and the related AD 2000 rules govern pressure parts sold into the European Union, with requirements on material traceability, testing and, for higher risk categories, third party inspection during manufacture. A flange or pressure vessel part headed to Europe usually needs a supplier who already works to these rules, since retrofitting the paperwork after the fact is harder than starting with a supplier who has it in place.

AMS specifications, published by SAE, cover specific alloys and processes used in aerospace, such as AMS 4928 for titanium forging stock. Where a drawing calls out an AMS number, it is naming an exact material and process specification, not a general grade, and a supplier should be able to show they forge to that spec routinely, not as a one-off.

ASTM and ASME specs, such as ASTM A105 for carbon steel flanges or A182 for alloy and stainless forgings, are the most common general callouts on industrial forging drawings. These are widely forged, so naming the exact spec on your RFQ mainly helps suppliers confirm they can meet the chemistry and testing it requires, rather than narrowing the field much.

Special process accreditation

NADCAP accredits specific special processes, heat treating, non-destructive testing, and welding among them, rather than the company as a whole. A supplier can be NADCAP accredited for heat treatment but not for NDT, so ask which processes the accreditation covers, not just whether the supplier “has NADCAP.” This matters most for aerospace and defense parts, where primes often require NADCAP accredited processes by name in the purchase order.

ITAR registration is not a certification in the same sense. It is a registration with the US State Department required to handle defense articles and technical data under the International Traffic in Arms Regulations. If your part or drawing is subject to ITAR, the supplier needs to be registered and your paperwork needs to reflect that, independent of any quality certificate they hold.

Material and inspection certificates

Separate from company level certifications, these documents cover one batch or one order.

EN 10204 3.1 is the most common request on industrial forgings, a certificate where the material manufacturer’s own inspector confirms the material or part meets the specified requirements, based on tests on that specific batch. A 3.1 certificate is not third party verified, but it is traceable to a specific heat and test result, which is usually enough for general industrial use.

EN 10204 3.2 adds an independent inspector’s validation on top of the manufacturer’s own certificate, used for higher risk parts where a customer or regulation wants an outside party involved.

First article inspection reports, covered in more detail in our guide on how to choose a forging supplier, document dimensions, hardness and any required mechanical tests on the first parts off a new die, before a full production run begins.

Common mistakes buyers make with certifications

Asking for “ISO certified” without saying which standard. ISO publishes hundreds of standards. A supplier can be certified to ISO 14001, an environmental management standard, and honestly answer “yes, we are ISO certified” without holding ISO 9001. Name the standard number.

Assuming certification covers every site a company operates. A supplier group with three plants may hold AS9100 at one location and not the others. If a specific site will make your part, confirm that site is the one on the certificate, not just the company name.

Treating NADCAP as one blanket accreditation. As covered above, NADCAP accredits specific processes. A shop can be accredited for heat treatment and still send its NDT to a subcontractor who holds a separate NDT accreditation. Ask which processes are covered and which, if any, are subcontracted.

Requiring a certification the part does not need. AS9100 and NADCAP add real cost and lead time to a quote, since certified suppliers carry the overhead of maintaining them. For a general industrial part with no aerospace, defense or pressure boundary requirement, requiring these certifications mainly narrows your supplier pool and raises price without changing the risk profile of the part.

What to put on the RFQ

State the exact requirement, not a general category:

• Name the standard and revision if known, such as “ASTM A182 F316” rather than “stainless steel forging.”
• Name any quality certification your program requires, such as AS9100 or IATF 16949, and whether a copy of the current certificate is needed with the quote.
• Name any special process accreditation required by name, such as NADCAP heat treatment, if your drawing or customer calls for it.
• State the material certificate level you need, such as EN 10204 3.1 or 3.2.
• Flag ITAR or export control status up front if it applies, so suppliers can confirm registration before quoting.

A supplier that already works to your exact spec will confirm it in one line. One that does not will either tell you plainly or go quiet, both of which save you time compared to finding out after the order is placed.

See also: qualifications to ask a forging supplier for, a matrix by industry with the place to check each one.

Frequently asked questions

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