What to Include in a Forging RFQ: Drawing, Material Spec, NDT and Quantity

A forging RFQ (request for quotation) is the document a buyer sends to a forging supplier to get a price, lead time and technical feasibility for a component. The quality of the quote you receive depends almost entirely on the quality of the RFQ you send. An RFQ that includes a dimensioned drawing, a precise material specification, heat treatment and NDT requirements, quantities, and certification needs can be quoted accurately within days. An RFQ with only a sketch and “alloy steel” can take weeks of back-and-forth and still produce a quote with large contingencies built in.

At a Glance: Forging RFQ Checklist

Why RFQ Quality Determines Quote Quality

Forging suppliers price risk. When an RFQ leaves questions open, the estimator has two choices: ask for clarification, which delays the quote, or assume the worst case, which inflates the price. A buyer who omits the heat treatment condition may receive a quote that assumes quench and temper with full mechanical testing, when normalising would have been acceptable. A buyer who omits annual volume may receive an open die forging quote with heavy machining stock, when a closed die route with tooling would have been far cheaper per piece.

A complete RFQ removes these assumptions. It lets the supplier choose the right process route, the right raw material size and the right inspection plan the first time.

1. The Drawing: The Single Most Important Document

Finished Part Drawing

Always send the finished machined part drawing with full dimensions, tolerances and the current revision. The forging supplier uses it to design the forging envelope — the shape that will be forged before machining — and to calculate machining allowances. Send native CAD (STEP or IGES) alongside the PDF wherever possible. A 3D model lets the supplier calculate volume and weight accurately and run forging simulations for complex closed die parts.

Forging Drawing (If You Have One)

Some buyers, especially in aerospace, defence and oil & gas, specify the forging drawing themselves, including parting line, draft angles and grain flow direction. If you have one, include it. If you do not, say so clearly and ask the supplier to propose the forging design. Experienced suppliers will recommend a near-net shape that reduces material and machining cost.

Critical Characteristics

Mark key characteristics and any features where grain flow orientation matters. For fatigue-loaded parts such as shafts, flanges and landing gear components, grain flow requirements directly influence the forging method chosen.

2. Material Specification: Grade, Standard and Supplementary Requirements

“Alloy steel” or “stainless steel” is not a material specification. Specify the exact grade and the governing standard — for example AISI 4340 to AMS 6415, EN19 to BS 970, ASTM A182 F53, or SA-508 Grade 3 Class 1. Include any supplementary requirements:

• Melting route (air melt, vacuum degassed, ESR, VAR)
• Cleanliness or inclusion rating requirements
• Restricted chemistry (for example low sulphur or controlled carbon equivalent)
• Approved mill list, if your customer restricts raw material sources
• Country-of-melt restrictions, such as domestic-melt or DFARS requirements for US programmes

These details can change raw material cost significantly and determine which mills the supplier can buy from.

3. Heat Treatment and Mechanical Properties

State the required delivery condition — normalised, annealed, quenched and tempered, solution annealed, or precipitation hardened and the mechanical properties the part must meet. Include:

• Tensile strength, yield strength, elongation and reduction of area
• Hardness range
• Impact test requirements (Charpy temperature and minimum energy)
• Test location — test coupon, prolongation or sacrificial part
• Testing frequency (per heat, per heat treatment lot, or per piece)

Test location is often overlooked. Testing from a prolongation on each forging is more expensive than testing from a separately forged coupon, and the supplier needs to know which is required to plan the forging envelope.

4. NDT and Inspection Requirements

List each NDT method and its acceptance standard. “UT required” is not enough. Specify the standard (for example ASTM A388, EN 10228-3, or a customer specification) and the acceptance class. Include:

5. Quantities: Prototype, Batch and Annual Volume

Quantity is the single biggest driver of process route and unit price. Always give three numbers:

• Prototype or first article quantity
• Typical batch or call-off size
• Estimated annual volume and programme life

A part ordered in quantities of five per year is usually best made by open die forging and machining. The same part ordered at 2,000 per year may justify closed die tooling, which raises the upfront cost but cuts the per-piece price sharply.

6. Delivery Condition and Scope

Be explicit about what you want delivered:

• As-forged (black) forging
• Proof machined or rough machined (often required for UT)
• Finish machined to drawing
• Sub-assembly, including fasteners, coating or painting

Forge-to-finish suppliers can quote the complete scope, which reduces your supplier count, logistics and documentation handoffs.

7. Certification and Documentation Requirements

This distinction is extremely important.

State the documentation you need at delivery so the supplier can include it in the price:

• EN 10204 Type 3.1 or 3.2 material certificates
• Quality system requirement (ISO 9001, AS9100D)
• Sector approvals such as IBR, API 6A / 20B, ABS, IRIS, PED
• Third-party inspection agency (Lloyd’s, BV, TÜV, DNV, IRS)
• Export documentation, packing and marking standards

8. Commercial Details

Finally, include the target delivery date, delivery terms (Incoterms for exports), payment terms and quote validity you need. If you have a target price, sharing it helps the supplier propose alternative routes or materials that meet it.

Common RFQ Mistakes That Delay Quotes

• Sending an outdated drawing revision
• Specifying a material family instead of a grade and standard
• Leaving out heat treatment condition or mechanical properties
• Giving only the order quantity, not the annual volume
• Not stating NDT acceptance standards
• Omitting third-party inspection requirements, which are then added later at extra cost

How Vinir Engineering Handles Your RFQ

Vinir Engineering reviews every RFQ with its engineering and quality teams together, so feasibility, process route and inspection plan are considered from the first response:

• All critical processes in-house — forging, heat treatment, CNC machining, NDT and assembly
• Open die, closed die, ring rolling and radial forging under one roof, so the process route is chosen on merit
• AS9100D certified across all four manufacturing units, with IBR, ABS and API approvals
• NABL-accredited in-house test lab for mechanical and chemical testing
• 42 years of production history across defence, aerospace, nuclear, oil & gas, rail and power

Frequently Asked Questions