API announced that the 10th edition of API 603, *Corrosion-resistant, Bolted Bonnet Gate Valves—Flanged and Butt-welding Ends*, had been published, with an API Monogram Program effective date of February 1, 2026. For buyers, the practical task is not merely changing a year in the valve data sheet. It is making the quotation basis auditable.
Quick buyer verdict
For a new API 603 inquiry, state the exact edition and project cut-off date. Require the bidder to identify the offered materials, pressure-temperature basis, ends, trim, testing, documents and every deviation. A generic line such as “gate valve to API standard” is not enough for technical or commercial comparison.
Eight RFQ fields to lock before bid comparison
| RFQ field | Minimum information to request | Why it matters |
|---|---|---|
| Governing documents | API 603 edition, ASME B16.34 edition and project specification hierarchy | Prevents bidders from using different design bases. |
| Service conditions | Fluid composition, concentration, contaminants, pressure, temperature and corrosion allowance | “Corrosion resistant” does not select an alloy by itself. |
| Materials | Body, bonnet, wedge, stem, seats, bolting, gasket and packing grades | Names such as stainless or duplex are too broad for approval. |
| Size and rating | NPS/DN, Class/PN, full or reduced port where applicable | Defines the commercial and pressure boundary basis. |
| End connections | Flanged facing and finish, or butt-weld end bore and schedule | Avoids site-fit and welding-scope surprises. |
| Operation | Handwheel, gearbox or actuator; orientation; required torque/thrust data | Confirms access, operability and automation scope. |
| Inspection and tests | Shell, closure, backseat where applicable, NDE, PMI and acceptance criteria | “Tested” is not a reviewable inspection plan. |
| Documents and deviations | GA, data sheet, MTCs, procedures, ITP, test records, deviation list and document schedule | Makes compliance traceable before shipment. |
API Monogram effective date is not the same as every project adoption date
API's notice sets February 1, 2026 as the Monogram Program effective date for the 10th edition. A project may still name a different contractual edition because of its specification freeze, jurisdiction, owner standard or purchase-order date. The RFQ should therefore state one controlled basis and require written approval for any proposed edition substitution.
Do not claim compliance from a marketing page alone. Ask for the manufacturer's applicable licence scope when an API Monogram is contractually required, and confirm the exact product standard and facility in API's directory.
Corrosion resistance starts with the process data
API 603's title does not make every listed material suitable for every corrosive fluid. The buyer should disclose the actual medium, concentration, chlorides or other contaminants, water content, operating and upset temperatures, cleaning chemicals, solids, velocity concerns and any sour-service requirement.
The supplier should then state the material basis for all wetted and pressure-retaining parts. If duplex, super duplex or another alloy is proposed, request the exact grade, applicable material standard, heat treatment, PMI scope, welding controls and any additional corrosion or impact-test requirements from the project specification.
Suggested RFQ wording
Gate valve shall be quoted to API 603, 10th Edition, and the project-specified editions of ASME B16.34 and referenced dimensional/testing standards. Supplier shall state all pressure-retaining, wetted, trim, bolting, gasket and packing materials; confirm suitability for the stated service envelope; identify end-connection details, operator requirements, inspection/testing and document deliverables; and list every deviation. No standard edition, material or test substitution applies without written purchaser approval.
Bid-review status matrix
| Supplier response | Status | Buyer action |
|---|---|---|
| Exact editions, complete materials, service basis, tests, documents and deviations are stated | Green | Continue technical and commercial alignment. |
| API 603 is named but alloy details, test acceptance or document scope is incomplete | Yellow | Issue a clarification before bid normalization. |
| Edition is unclear, “equivalent” materials are unapproved, or Monogram claims are unsupported | Red | Hold the offer until the compliance basis is corrected. |
Product and inquiry links
Review XHVAL's industrial gate valve range and industrial valve portfolio. For a useful quotation, send the medium and composition, design and operating conditions, size, class, end connections, material preferences, operator, testing, inspection, documentation and required standard editions.
Final takeaway
The API 603 10th-edition transition should trigger a controlled RFQ review, not a one-line document update. Lock the contractual edition, make the corrosion-service data explicit, and require evidence that lets engineering, quality and procurement compare the same scope.