A quote-ready weldment package defines the finished assembly, the governing requirements, and the evidence needed to accept it—without forcing the fabricator to invent design intent.

TL;DR

A useful weldment RFQ identifies every component and revision, the assembled geometry that matters, functional datums, weld symbols and governing code, base and filler material requirements, distortion-sensitive features, inspection and NDT expectations, surface finish, quantity, delivery, and required records.

Do not make the fabricator infer whether a tolerance applies before welding, after welding, after stress relief, or after machining. Ask suppliers to separate fabrication, tooling, outside processing, inspection, and one-time qualification costs so different manufacturing plans can be compared honestly.

A Weldment Is an Assembly and a Process Plan

A machined component may begin with one controlled material blank. A weldment can combine cut plate, tube, formed sheet, machined details, purchased hardware, fixtures, welding sequences, straightening, heat treatment, machining, NDT, and coating. The RFQ must control the result without pretending that these steps are interchangeable.

AWS D1.1/D1.1M:2025 covers structural welding requirements for steel, including qualification, fabrication, inspection, and acceptance [1]. It is influential, but it is not a universal default for every welded product or material. The design authority must identify the code, customer specification, or internal standard that actually governs the work.

Weldment RFQ Package

RFQ element What to provide Failure prevented
Assembly definition Assembly drawing, component drawings, CAD, BOM, and revision Quoting the wrong configuration
Material Grade, form, condition, thickness, substitutions, and certification Unapproved stock or mixed requirements
Weld definition Symbols, joint details, size, length, location, contour, and code Shop interpretation of design intent
Datum scheme Functional datums and measurement setup Inspecting a flexible assembly arbitrarily
Finished geometry Dimensions and tolerances in the accepted condition Dispute over as-welded versus final dimensions
Distortion controls Sensitive surfaces, flatness, alignment, and machining allowance Unrecoverable movement
Qualification Required WPS, PQR, welder qualification, or customer approval Qualification discovered after award
Inspection Visual, dimensional, NDT, sampling, and acceptance criteria “Inspect welds” without a defined decision
Finish Blast, pickle, passivate, plate, paint, powder coat, masking, and color Rework after coating
Records Material, weld, personnel, process, NDT, dimensional, and finish evidence An acceptable part with unusable documentation

Define the Accepted Condition

The drawing should state when a requirement applies:

  • component before assembly;
  • fit-up before welding;
  • as-welded;
  • after stress relief or other thermal processing;
  • after straightening;
  • after finish machining;
  • after coating; or
  • at final acceptance.

This matters because welding creates localized heating and cooling. NIST work on weld residual stress and distortion describes why welding process simulation and sequence control are used to predict movement rather than treating it as random shop behavior [2]. The practical RFQ question is not “Can you hold this tolerance?” It is “At which stage must this tolerance exist, and what manufacturing allowance is available to recover it?”

Datums Must Reflect Function

Large frames and thin fabrications can change shape under their own weight, under clamps, or when placed on a surface plate. A datum scheme should tell the supplier how the assembly is functionally located.

For each critical relationship, define:

  1. the primary mounting plane or functional support;
  2. the secondary locating feature;
  3. the tertiary feature that arrests the remaining degree of freedom;
  4. the allowed restraint or fixture condition during inspection;
  5. whether machining creates the final datum after welding; and
  6. whether unloaded free-state requirements also apply.

Avoid dimension chains that make the shop satisfy the same functional relationship several different ways. If a mounting pattern is the real interface, control the mounting pattern—not a collection of reference dimensions to unrelated raw edges.

Do Not Hide Weld Requirements in Notes

The package should answer:

  • Which welds are continuous, intermittent, seal, tack, cosmetic, or prohibited?
  • Are weld symbols complete and tied to the correct side and joint?
  • Are backing, back gouging, run-on tabs, or access holes allowed?
  • Are temporary attachments allowed, and how must they be removed?
  • Is grinding permitted, required, or prohibited?
  • What contour is required?
  • Are weld starts, stops, and spatter restricted near a functional surface?
  • Are dissimilar materials or coated components involved?
  • Does the code require preheat, interpass control, post-weld treatment, or qualification?

“Weld all around” and “grind smooth” can each create cost and risk far beyond their apparent simplicity. Specify them only where the product requires them.

Make Distortion a Joint Planning Topic

Ask the supplier to identify:

  • proposed fixture concept;
  • weld sequence;
  • expected movement;
  • features requiring added stock for later machining;
  • whether presetting or controlled straightening is anticipated;
  • thermal-process sequence;
  • inspection state;
  • lifting and support points; and
  • geometry that is high-risk at the requested tolerance.

A strong fabricator may propose split components, different joint access, balanced welding, a machining-after-weld route, or a tolerance change on a nonfunctional feature. Treat those as manufacturing proposals requiring design review—not silent deviations.

Inspection Must Name a Method and a Decision

“Inspect per drawing” is not enough when the drawing does not establish inspection scope.

Requirement Useful RFQ definition
Visual weld inspection Scope, timing, acceptance standard, and inspector qualification
Dimensional inspection Characteristics, datum setup, condition, method, and report format
NDT Method, coverage, technique/specification, personnel qualification, and acceptance criteria
Leak or pressure test Medium, pressure, duration, allowable loss, safety boundary, and record
Destructive qualification Coupon, orientation, test, frequency, and disposition
Coating inspection Preparation, thickness or coverage, cure, color, adhesion, and evidence

OSHA separately identifies hazards in welding, cutting, and brazing work and points employers to applicable standards and controls [3]. An RFQ is not the supplier's safety program, but it should not prescribe an unsafe sequence or omit hazardous coatings, residues, confined geometry, or customer-property conditions that affect planning.

Separate Commercial Assumptions

Request a quote breakdown for:

  • material;
  • cutting and forming;
  • bought-out components;
  • fixtures and gauges;
  • welding;
  • thermal processing;
  • machining;
  • NDT and inspection;
  • finishing;
  • packaging;
  • first-article or qualification work; and
  • recurring unit price.

Also state annual usage, release quantity, batch size, first required date, repeat-order expectation, packaging constraints, and whether tooling is buyer-owned. A prototype price based on temporary fixturing should not be mistaken for a production price.

Final RFQ Release Check

  • Every drawing, model, BOM, and specification has a revision.
  • Components and purchased hardware reconcile with the assembly.
  • Material and allowed substitutions are explicit.
  • Weld code and weld symbols are identified where applicable.
  • Functional datums and accepted condition are defined.
  • Distortion-sensitive geometry is visible to the bidder.
  • Post-weld thermal processing and machining sequence are clear.
  • NDT and dimensional acceptance criteria are stated.
  • Finish, masking, and cosmetic requirements are bounded.
  • Required certificates and reports are listed.
  • Quote assumptions, exclusions, tooling, and lead time must be returned.

The Best RFQ Invites a Manufacturable Counterproposal

Release a controlled baseline, then give qualified fabricators a structured way to identify conflicts and propose alternatives. The buyer should be able to compare the suppliers' intended routes, not merely their totals. Use the U.S. Manufacturing Directory to build a capability-first fabrication shortlist.

References

  1. American Welding Society, AWS D1.1/D1.1M:2025 — Structural Welding Code: Steel. Scope is limited to the code's stated structural-steel application.
  2. National Institute of Standards and Technology, Modeling and Measurement of Welding Residual Stress and Distortion.
  3. Occupational Safety and Health Administration, Welding, Cutting, and Brazing.
Best Practices