Why a reliable quotation begins with a shared understanding of the job
Two suppliers can receive the same drawing and return quotations that appear comparable, while planning to deliver different things. One may include final machining, weld testing, coating protection and a complete inspection package. The other may have priced a welded structure with several of those activities excluded or left undefined.
The difference is not necessarily manufacturing efficiency. It may be a difference in how the request for quotation (RFQ) has been understood.
In heavy fabrication, a dependable price and delivery commitment require more than a material weight and an estimate of welding hours. They require agreement on the component’s condition at delivery, the manufacturing requirements, the evidence needed for acceptance and the responsibilities at each interface.
A technical RFQ review helps establish that agreement before purchasing, cutting or fabrication begins. Its purpose is to turn incomplete assumptions into clear decisions while those decisions are still relatively inexpensive to change.
1) Define what the supplier is actually being asked to deliver
A drawing describes the product, but it does not always describe the complete supply scope.
Before preparing a firm quotation, the customer and supplier should establish whether the requirement is for cut parts, a welded assembly, a machined fabrication or a finished component ready for installation.
Questions worth resolving include:
- Who supplies the raw material and purchased components?
- Are final machining and surface treatment included?
- Are bushes, fasteners or other assembly items part of the delivery?
- What inspections, reports and material records are required?
- Who provides transport supports, packaging and surface protection?
- Does the requested date refer to dispatch or arrival at the customer’s site?
These decisions affect both cost and the production route. A fabrication delivered before final machining is a different scope from a component delivered with verified mounting interfaces.
Clear boundaries also help purchasing teams compare quotations on an equivalent basis.
2) Establish one technical package for quotation
An RFQ may contain drawings, 3D models, specifications, purchasing notes and customer standards. The first review should confirm that these documents describe the same configuration.
A practical quotation package should identify the relevant part numbers, revision levels, quantities and referenced requirements. Where a drawing calls up another specification, that specification needs to be available for review rather than assumed to contain familiar requirements.
Conflicts should be raised explicitly. If a model and drawing show different geometry, the supplier should not silently select the version that is easier to manufacture. The applicable document hierarchy and the intended configuration need clarification.
It is also important to distinguish a budgetary enquiry from a production-ready package. An early design can support an indicative estimate, provided the assumptions and unresolved items are visible. It should not be presented as a fully reviewed production commitment.
3) Check the manufacturing route, not only individual operations
Having the equipment for each operation does not automatically establish that the complete component can be produced efficiently through the proposed sequence.
The review should consider how the work will move through material preparation, forming, fit-up, welding, machining, inspection and finishing.
For a large welded structure, useful questions include:
- Can the joints be reached in the intended assembly sequence?
- Can the component be supported and repositioned between operations?
- Is there enough space for the required tools, clamps and inspection access?
- Will later assembly stages restrict access to areas that must be checked?
- Are any external processes or specialist services required?
This connected approach is consistent with TWI’s welding quality guidance, which treats technical requirements, personnel, procedures, equipment, inspection and traceability as related elements of manufacturing control.
The RFQ stage does not need a fully detailed work instruction for every operation. It does need enough review to identify feasibility concerns and the conditions on which the quotation depends.
4) Identify the features that determine final fit
Not every dimension presents the same manufacturing challenge. Distant mounting points, aligned bores, machined faces and other functional interfaces can determine the fixturing, machining and inspection approach for the whole component.
The review should establish:
- which features are critical to the customer’s assembly
- which datum system governs their relationships
- which requirements apply to the welded condition and which to the finished component
- where machining allowances are needed
- whether the proposed measurement approach can verify the specified tolerances
Consider a welded machine base with mounting faces at opposite ends. Pricing the machining of each face separately may overlook the setup needed to control their relationship across the entire structure.
Likewise, a requirement for flatness should not be interpreted without understanding the specified measurement and support conditions where these are relevant.
If a requirement is unclear or difficult to achieve, the supplier should raise a specific technical question. Any proposed change to a tolerance or interface remains subject to the customer’s approval.
5) Include material, welding and acceptance requirements in the scope
A material description should be sufficiently precise for purchasing and fabrication. Depending on the project, the review may need to confirm the grade, product standard, delivery condition, thickness, certification and traceability requirements.
A proposed substitute should be identified as an alternative for approval, not treated as automatically interchangeable.
Welding requirements also deserve early attention. The responsible technical personnel should determine whether the specified joints and materials are covered by appropriate procedures and qualifications, and whether further preparation or qualification work is needed.
Acceptance requirements must be priced and scheduled alongside manufacturing. The RFQ review should clarify the required non-destructive testing methods, extent, acceptance criteria, inspection stages, witness points and final documentation, where applicable.
For example, Volvo Group’s public supplier quality manual includes a technical specification review and capacity assessment among RFQ response requirements, and states that the costs of meeting quality requirements should be included in quotations. This is a customer-specific example, not a universal checklist for every fabrication project.
The broader practical lesson is straightforward: acceptance activities are part of the work being offered, not an undefined addition after production.
6) Separate first-off costs from repeat-production assumptions
The first component may require fixture design, programming, trial setups, additional measurements and customer review. Later units may benefit from that preparation, but only if the configuration and production conditions remain sufficiently consistent.
An RFQ should therefore distinguish:
- prototype or first-off quantity
- normal batch size
- forecast annual demand
- firm order quantities and delivery releases
- one-time tooling or engineering costs
- first-off approval requirements
An annual forecast of multiple units does not necessarily mean they will be ordered or manufactured together. Small, irregular releases can require repeated setups and different material purchasing arrangements.
A transparent quotation explains which quantity and release assumptions support the price. It also distinguishes first-off lead time from the expected timing of subsequent batches.
This gives the customer a clearer basis for deciding how to structure the order.
7) Build the delivery commitment around real dependencies
A requested delivery date should be checked against the full route, not only the estimated time on production equipment.
Material availability, fixture preparation, technical approvals, external processing, inspection and transport preparation can all affect the schedule. Available machine capacity is only one part of that assessment.
The quotation should make its timing basis clear. If the lead time depends on drawing approval, material confirmation or a customer decision, the dependency should be identified rather than hidden inside a general promise.
The same applies to first-off approval. If repeat production cannot proceed until the customer accepts the initial component, the review should establish how that approval fits into the overall programme.
Good scheduling does not remove every uncertainty. It makes the important dependencies visible early enough for both parties to manage them.
8) Make qualifications and alternatives easy to evaluate
A supplier can respond constructively to an incomplete RFQ without pretending that every question has already been resolved.
The response should separate confirmed requirements from:
- assumptions used for pricing
- items excluded from the scope
- technical questions awaiting an answer
- alternatives proposed for customer approval
- conditions affecting price or lead time
These categories should not be mixed together. An assumption is not an approval, and a proposed alternative is not permission to depart from the specified requirement.
As an illustrative example, imagine two quotations for the same welded frame. One includes final bore machining, specified weld testing and a dimensional report. The other excludes those activities.
The lower headline price cannot establish which offer is better value until the scope has been aligned. A short clarification at the quotation stage is more useful than discovering the difference when the finished frame is awaiting acceptance.
9) Carry the agreed quotation basis into production
The value of a technical review is lost if its conclusions remain only in the estimator’s notes or an email exchange.
When an order is placed, the production handover should confirm that the purchase order and technical package match the agreed quotation basis. Any differences need review before affected work is released.
A practical handover should carry forward:
- the agreed scope and document revisions
- approved clarifications and alternatives
- material and traceability requirements
- critical interfaces and inspection obligations
- tooling and external-process responsibilities
- delivery assumptions and approval dependencies
- outstanding actions, with named owners
Not every open item must prevent every preparatory activity. The important distinction is whether it affects the work being authorised. Purchasing a specific material, for example, should not proceed on an unresolved material assumption.
This closes the gap between what was quoted, what was ordered and what the workshop is instructed to produce.
A practical conclusion
A reliable heavy fabrication quotation is more than a price attached to a drawing. It is a clear statement of what will be delivered, which requirements apply and what conditions support the proposed cost and schedule.
Technical RFQ reviews help customers and suppliers identify ambiguities before they become purchasing errors, unsuitable setups, missing inspections or late delivery discussions.
For OEMs, the benefit is a stronger basis for comparing offers and planning production. For fabrication partners, it is a more dependable starting point for controlled execution.
At SL Industries, our capabilities span cutting, forming, welding, CNC machining, shotblasting and painting. For an upcoming fabrication enquiry, contact our team to discuss the technical package, required delivery condition and project scope.
E-mail: info@sl-industries.com
