API's public balloting system listed a ballot for the 10th edition of API 594, *Check Valves: Flanged, Lug, Wafer, and Butt-welding*, from March 23 to May 1, 2026. That is an important standards signal, but it is not permission to quote an unpublished draft as a contract requirement.
Quick buyer verdict
Keep the currently published project basis explicit, then add a controlled clause for any later edition. Ask every supplier to identify the exact standard edition, check-valve type, operating envelope, closure behaviour and test/document package behind the offer.
What the ballot does 鈥� and does not 鈥� mean
API's Standards Plan identifies API 594 Edition 9 as the published check-valve document, while the public ballot record identifies work on Edition 10. Until API publishes a new edition and the project adopts it, buyers should not assume draft clauses, dates or technical changes.
The practical response is version control. A vague line such as 鈥淎PI 594 latest edition鈥� can move technical and commercial scope after quotation. A stronger RFQ separates the bid basis from any post-award change mechanism.
Seven RFQ fields to lock now
| RFQ field | What to state or request | Why it matters |
|---|---|---|
| Governing edition | API 594, exact edition and project cut-off date | Prevents bidders from pricing different document sets. |
| Valve design | Swing, tilting-disc, dual-plate, axial/non-slam, lift or other defined type | Different closure dynamics and installation constraints are not interchangeable. |
| Service data | Medium, solids, density, viscosity, temperature and corrosion allowance | Material and internal geometry depend on real service. |
| Hydraulic envelope | Minimum/normal/maximum flow, differential pressure, pump trip and reverse-flow cases | Static class alone cannot define slam or chatter risk. |
| Installation | Size, class, ends, orientation, straight-run limits and available space | A technically suitable valve can still fail the piping layout. |
| Testing | Shell, seat, closure leakage, NDE and any dynamic verification | 鈥淭ested鈥� is not a reviewable acceptance basis. |
| Change control | How a newly published edition will be reviewed, priced and approved | Stops automatic, uncontrolled scope migration. |
Why tilting-disc searches need more than a product name
A real search term in the July 15 Ads data was 鈥渢ilting disc check valve.鈥� That is relevant product intent, but the type name alone does not establish suitability. Check-valve closure is a system event: disc travel, deceleration of forward flow, reverse velocity, pump inertia and pipeline surge behaviour interact.
For pump discharge or water-hammer-sensitive service, ask for the manufacturer's dynamic data or an agreed surge-analysis input set. Do not accept 鈥渘on-slam鈥� as a substitute for the operating envelope and selection basis.
Suggested RFQ wording
Check valve shall be quoted to API 594, [project-specified published edition], with valve type, size, class, end connection, materials, orientation and testing explicitly stated. Supplier shall review minimum, normal, maximum, pump-trip and reverse-flow cases; provide required dynamic/closure data for surge review; identify all assumptions and deviations; and separately state the technical, schedule and price effect of adopting any later API 594 edition published after the bid cut-off date. No edition change applies without written buyer approval.
Bid-review matrix
| Supplier response | Status | Buyer action |
|---|---|---|
| Exact edition, design, service envelope, tests and dynamic inputs are stated | Green | Continue technical and commercial comparison. |
| API 594 is named but edition or closure basis is missing | Yellow | Request a clarified data sheet before alignment. |
| Supplier claims compliance with an unpublished draft or changes basis without approval | Red | Hold the offer until the contractual standard is corrected. |
Product and inquiry links
Review 91探花's tilting plate check valve and broader industrial check valve range. For a useful quotation, send the service medium, flow range, pressure and temperature, pump-trip case, size, class, end connection, orientation, materials, testing, documents and project standard edition.
Final takeaway
The 10th-edition ballot is a reason to tighten RFQ version control, not to invent future requirements. Buyers can protect technical comparability today by fixing the published bid basis, collecting real closure inputs and requiring written approval for any later-edition transition.