How to Specify Stainless Steel Sheet for an International RFQ

A complete RFQ provides the details needed for suppliers to prepare comparable bids. Although the term “stainless steel sheet, 2 mm” provides a good start for a potential supplier to develop a proposal for this item, it leaves many questions unanswered. The assumptions made by suppliers about the requested item and grade may lead to quotes that seem competitive at first glance but actually represent different products.

For international purchasing managers, distributors and fabricators, a useful RFQ describes both the item being purchased and the evidence required to show that it meets the buyer’s specifications. In addition, the RFQ should provide information regarding transportation to the designated destination, handling of goods and costs included in the bid.

Start with the application and grade

Identify your application and grade. Describe the conditions that the material will experience and the final form of the material. Material for an indoor equipment enclosure, an exterior architectural panel or a component exposed to process chemicals may have different requirements. Include relevant temperatures, exposure conditions, cleaning methods and planned bending or welding operations.

Provide the required grade along with applicable standards and editions. A grade designation such as 304 or 316L is helpful; however, you will want to provide a defined basis for chemical composition, mechanical properties and supply conditions. For example, ASTM A240/A240M applies to stainless steel plate, sheet and strip for pressure vessels and general applications, with general requirements covered by ASTM A480/A480M.

When a supplier submits a designation under a standard that is equivalent, request a documented comparison and engineering approval prior to accepting the submission. Include application-specific requirements within your RFQ instead of relying solely upon familiarity with a commonly known grade designator.

Define dimensions and tolerances separately

Include nominal thickness, width and length using a consistent unit of measure. Use caution when simply specifying gauge; there may be confusion associated with it. Determine whether your requirement is for standard sheets or cut blanks, and provide drawings with revision numbers if the geometry is important.

Acceptance limits for nominal dimensions should accompany them. Specify the governing tolerance standard(s) and any tighter project requirements related to thickness, width, length, flatness and/or squareness. Have the supplier specifically list any deviation from these limits. Specifying “standard tolerance” is sufficient only if both parties have established which standard(s), product category(ies) and tolerance classes apply.

Define the edge condition (i.e., can edges be sheared or do they need to be deburred). Provide guidelines relating to the surface finishing (i.e., polishing or further processing) that affects the dimensions. Clearly indicate that any agreed-upon limits apply to the material as received by the receiving team.

Make the surface finish verifiable

Establish a recognized surface finish designation and relate it back to a recognized standard. Some common finish names are 2B mill finish, bright annealed finish and mechanically polished surfaces. These descriptions refer to various routes of manufacture and appearance. Words like “smooth” and “shiny” leave too much open to interpretation.

Agree on a reference sample where visible parts are involved and designate either one or both sides of the part to meet the finish requirement. Indicate polishing direction for adjacent panels requiring matching finishes. Where required by the application, establish surface roughness parameters (e.g., Ra), limits and measurement methods. A finish name alone provides no assurance of a given roughness value.

Indicate whether or not protective film is applied to the surface of the material. Confirm that any film applied is compatible with subsequent processes (especially laser cutting). Outline requirements for removal of any protective films and acceptable surface condition beneath films.

Separate material quantity from processing scope

Quantify each ordered combination of grade, thickness, size and finish. Provide sheet counts and, where applicable, estimate mass. Agree upon the pricing and invoicing method (actual weight, theoretical weight or price per sheet); determine what quantity variations are permissible. Distinguish trials from regular demand when quantifying.

Purchasers contacting Jianglin Steel, a China-based manufacturer and supplier of stainless steel and alloy products, may separate sheet procurement from requests for cutting, surface polishing, CNC machining or fabrication. Defining the operational scope of each allows the supplier to confirm their proposed scope of work as well as quote each requirement distinctly.

Document inspection and preserve traceability

Identify the documentation required for the material. If the project requires an EN 10204 type 3.1 inspection certificate, request it directly in the RFQ. This certificate contains results from specific inspection and is validated by the manufacturer’s authorized inspection representative, who must be independent of the manufacturing department. The certificate alone does not establish that an external inspection agency has certified the shipped goods.

Request chemical analysis and relevant mechanical test results against the ordered specifications. Obtain heat numbers as well as other identifying references connecting certificates to individual sheets or bundles; define how such connections must remain intact if the original material is cut into smaller pieces or repackaged.

Prior to ordering, specify the inspection scope, sampling methodology and acceptance criteria. Checks may cover dimensions, surface condition, markings and document consistency. For third-party inspections or additional testing, define who arranges the work, who pays and whether written release is required before shipment. Obtain documentation sufficiently early to allow review before dispatch.

Set packaging and delivery requirements

Detail packaging requirements depending on the transport route and unloading plans. Specify surface separation, edge protection, moisture protection, appropriate supports and maximum bundle weights when necessary. Request labels identifying the order, grade, dimensions, quantity and traceability references without damaging finished surfaces.

Designate the destination country and exact delivery location or port. State the agreed Incoterms rule, the named place or port and the edition. Verify which party handles freight, insurance, customs clearance and unloading under that rule; terms of payment and ownership transfer require separate agreement.

Differentiate the required dispatch date from the required arrival date. Request suppliers to list production lead time, estimated transit time, quotation validity and exclusions so the purchasing team can assess the full offer.

A short checklist before sending

• Application, grade, product standard and supply condition.
• Thickness, sheet size, dimensional tolerance limits and edge specifications.
• Finish, reference sample, protective film and processing drawings.
• Quantity by item, pricing basis and permitted quantity variations.
• Certificates, inspection requirements and traceability arrangements.
• Packaging, destination, delivery terms and required dates.

Lastly, have each bidder return a compliance statement listing exceptions against your RFQ. A quotation with its assumptions stated is easier to judge, as it shows how each bidder proposes to produce and deliver the material. Resolving issues between buyer and seller before issuing the purchase order provides an agreed specification for production, delivery and acceptance.