The short answer
A complete valve RFQ states the service and fluid, valve type and function, size, pressure class, design standard, body, trim and seat materials, end connections, bore, design pressure and temperature, any sour-service or emissions requirement, actuation and fail position, quantity, documents, inspection, delivery location and date. Most of these fields come from the approved datasheet; a buyer who isn't the engineer should attach it rather than guess.
The fields, and who decides them
| Field | Why it matters | Decided by |
|---|---|---|
| Service and fluid | Drives materials, testing and documents | Engineer / datasheet |
| Valve function and type | Isolation, check or control; ball, gate, check, plug | Engineer / datasheet |
| Size (NPS) and bore | Full or reduced bore matters where pigs must pass | Engineer / datasheet |
| Pressure class | ASME class from 150 to 2500 for API 6D valves | Engineer / datasheet |
| Design standard | e.g. API 6D, or ASME B16.34 for general valves | Engineer / datasheet |
| Body, trim and seat materials | Must suit the fluid and temperature | Engineer / datasheet |
| End connections | Flanged, butt-weld or other, with facing | Engineer / datasheet |
| Design pressure and temperature | Confirms the rating basis | Engineer / datasheet |
| Sour service (H2S) | Material requirements under ISO 15156 where specified | Engineer / datasheet |
| Fire-safe or fugitive-emissions class | Type-test evidence such as API 607 or ISO 15848-1 where specified | Engineer / datasheet |
| Actuation and fail position | Manual, gear, or powered; fail-open, fail-closed or stay-put | Engineer / datasheet |
| Quantity and spares | Include seal kits or spare actuators if needed | Buyer |
| Documents required | Material certificates, test reports, dimensional checks | Buyer / project specification |
| Inspection before shipment | Witnessed or reviewed, and by whom | Buyer / project specification |
| Approved manufacturers | Some projects allow only listed makers | Buyer / end client |
| Delivery location and required date | Sets freight, clearance and delivery planning | Buyer |
If you are not the responsible engineer, attach the approved datasheet or valve schedule instead of filling engineering fields yourself. We ask about gaps; we don't fill them with assumptions.
Sending it
Our quotation form takes the datasheet, BOQ or drawings as attachments, plus the quantity, delivery state and city, and the required date. Then read what documents to expect, or return to the pipeline valve procurement guide.
Sources
External facts on this page come from these sources, each read on 15 October 2026. Regulations change; requirements for your vehicle are confirmed during quotation and clearance. This guide is not legal or financial advice.
- API SPEC 6D: Specification for Valves, 25th edition (Nov 2021; Addendum 3, Mar 2025) — American Petroleum Institute webstore
- ASME B16.34-2025: Valves — Flanged, Threaded, and Welding End — ASME
- ISO 15156-1:2020: Materials for use in H2S-containing environments — International Organization for Standardization
- API STD 607: Fire Test for Quarter-turn Valves and Valves Equipped with Non-Metallic Seats, 8th edition (Oct 2022) — American Petroleum Institute webstore
- ISO 15848-1:2015 (Amd 1:2017): Industrial valves — fugitive emissions type testing — International Organization for Standardization