Buyer note: confirm assumptions before quoting
Lead time, MOQ, yield, leak-test scope, machining scope, and landed cost depend on the drawing, alloy, inspection plan, annual volume, and destination market. For current supplier facts, review the supplier capability sheet or send an RFQ package.
# Valve Body Spool Bore RFQ Checklist: Surface Finish, Honing, Cross-Hole Deburr, Cleanliness, and Inspection Evidence
Hydraulic valve body RFQs often specify ports and threads, but the hardest launch risk is frequently spool-bore performance: surface finish, straightness, cross-hole burrs, and cleanliness. One supplier quotes basic boring/reaming, another assumes honing and aggressive wash, and neither assumption is visible until valves stick, leak internally, or fail functional testing.
This checklist helps you write a quoteable valve body RFQ where bore finish and cleanliness are treated as first-class requirements.
Useful Bohua routes:
- •Valve body manufacturer page
- •Valve body application overview
- •Valve body OEM quote route
- •Hydraulic valve product example
- •Structured RFQ upload
1) Identify the functional bores (and which ones are spool-critical)
In the RFQ, group bores by function:
- •spool bore(s) (performance-critical)
- •sleeve bores (if a sleeve is used)
- •pilot/locating bores (alignment)
- •auxiliary bores (non-critical)
If the drawing has multiple spool bores, list each one and whether it has unique finish requirements.
2) Surface finish requirement (Ra) and where it applies
Spool performance is sensitive to finish and texture direction.
In the RFQ, state one of:
- •explicit surface finish requirement (example: Ra __ for spool bores), or
- •“supplier propose spool-bore Ra target + process method; include measurement plan in quote”
Also specify whether finish is required:
- •after honing/lapping (final acceptance), and
- •whether coating/anodize is allowed on the bore (often no, but the RFQ must say it)
3) Geometry expectations: roundness / cylindricity / straightness
Even with a good Ra number, taper and out-of-round can cause leakage and sticking.
If your program controls these, state:
- •roundness / cylindricity requirement for spool bores (if any)
- •straightness requirement or max taper (if any)
- •datum reference for inspection
RFQ CTA
Have a casting project? Upload your drawing for a fast, structured quote review.
Send the drawing, target alloy, finishing scope, MOQ, and delivery timing. Bohua will review it like a real sourcing project, not a generic contact request.
If you do not have numbers yet, require the supplier to propose geometry controls and document them as quote assumptions.
4) Machining process assumptions (so quotes match)
State whether the supplier should assume:
- •boring + reaming only, or
- •honing, lapping, or polishing steps
If honing is required, request the supplier to state:
- •honing method and tooling plan
- •whether bores are gauged in-process
- •how tool wear is controlled and documented
5) Cross-hole burr control + cleanliness (the hidden failure mode)
Many valve bodies have cross-drilled passages intersecting spool bores. In the RFQ, define:
- •deburr expectation (including internal edges)
- •cleanliness requirement (wash, dry, protect)
- •whether a cleanliness verification method is required (supplier-proposed is acceptable if documented)
If you have a “no loose burr” or contamination limit, state it. Otherwise ask suppliers to propose a practical cleaning + protection plan.
6) Inspection evidence: what records you want for approval
For spool-bore risk, request at least one of:
- •air-gauge records for spool bores
- •bore size + geometry report (supplier method stated)
- •surface finish measurement record (Ra) with measurement location definition
- •CMM report for datum scheme and relationships (when relevant)
Define whether evidence is required for:
- •first article only, or
- •ongoing sampling in production
Copy-paste RFQ starter (spool bore + cleanliness)
> Valve body spool-bore RFQ (copy-paste)
> Files: 2D PDF rev __ ; STEP __
> Functional bores: spool bores __ ; sleeve bores __ ; auxiliary bores __
> Surface finish: spool bore Ra __ / supplier propose __ ; acceptance after final finish yes/no __
> Geometry: roundness/cylindricity/straightness requirements __ ; datum reference __
> Process: boring/reaming vs honing/lapping __ ; in-process gaging method __
> Deburr + cleanliness: cross-hole burr control __ ; wash/dry/protect __ ; verification method __
> Inspection records requested: air-gauge __ ; surface finish __ ; CMM/datum report __ ; material cert __ ; traceability fields __
> Quantity + schedule: prototype __ ; annual volume __ ; timing __ ; destination + Incoterm __
Submit a structured RFQ (drawing-ready)
Project CTA
Sourcing Precision Valve Bodies?
Send your drawing for a structured DFM review, quote scope, and project-specific timing discussion.