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.
# Pump Housing Bearing-Seat + Runout RFQ Checklist: Datums, Concentricity, Machining Scope, and Inspection Evidence
Pump housing quotes often focus on “pressure-tight” and leak testing, but many pump programs fail at assembly because bearing seats and shaft/seal bores were never defined in a quoteable way. Different suppliers assume different machining plans, different datums, and different inspection evidence — and the differences only show up when the bearing presses in crooked, the shaft runout is out of control, or the seal interface leaks.
This checklist helps procurement + SQE teams write a pump housing RFQ that makes bearing-seat and runout requirements visible in the quote.
Useful Bohua routes:
- •Pump housing manufacturer page
- •Pump housing application overview
- •Pump housing OEM quote route
- •A356 pressure-tight pump housing RFQ route
- •Structured RFQ upload
1) Identify which bores are functional (do not treat “bore” as one thing)
In the RFQ, list each functional bore group separately:
- •bearing seat(s)
- •shaft seal bore(s) / seal land(s)
- •impeller or rotor locating bore(s)
- •pilot bores used for assembly alignment
If the drawing is complex, add a one-page “critical feature map” that labels each bore group and which stage controls it (as-cast vs machined).
2) State the datum scheme used for machining and inspection
Bearing-seat and runout requirements only make sense relative to datums.
In the RFQ, specify:
- •primary datum (often a mounting face or reference face)
- •secondary datum (often a locating bore or pilot)
- •tertiary datum (anti-rotation or second face)
If your drawing already defines A/B/C, call out that CMM reports must reference those datums. If you do not know the best datum scheme, ask the supplier to propose one and list it as a quote assumption.
3) Concentricity / runout requirements: make them quoteable
Teams often write “runout tight” without saying what is measured. In the RFQ, define:
- •feature: which bearing seat / seal bore
- •reference: runout relative to which datum axis
- •measurement method: CMM vs roundness tester vs air gauge + spindle fixture (supplier-proposed is acceptable if disclosed)
- •acceptance stage: after final machining (recommended for final acceptance)
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 cannot define numeric values yet, require the supplier to propose values and document them in the quote assumptions.
4) Machining scope + stock allowance (so suppliers quote the same risk)
For bearing-seat stability, define:
- •which bores are fully machined vs partially cleaned up
- •whether honing/reaming is required
- •whether heat treatment happens before/after critical machining (distortion risk)
- •stock allowance assumptions (if your program has a preference)
If you need A356-T6, state whether the bearing seats are finished after T6 (common when distortion matters).
5) Inspection evidence: what records should ship with samples
For bearing-seat / runout risk, request at least one of:
- •CMM report covering datum scheme + bore size + positional relationships
- •air-gauge record for bearing seats (if used)
- •roundness / cylindricity report when required by your design
- •gage R&R / MSA evidence if your approval system requires it
State whether you want first-article (FAI) records only, or ongoing sampling records for production.
6) Assembly context (so the supplier understands why you care)
Include:
- •bearing type (ball/roller/bushing) and fit (interference/clearance)
- •whether press-fit force or insertion behavior is critical
- •seal type and sensitivity (lip seal vs mechanical seal)
- •operating speed and any noise/vibration sensitivity notes
Even a short note helps suppliers avoid quoting the wrong machining and inspection plan.
Copy-paste RFQ starter (bearing seat + runout)
> Pump housing bearing-seat RFQ (copy-paste)
> Files: 2D PDF rev __ ; STEP __
> Functional bores: bearing seat __ ; seal bore __ ; pilot/locating bores __
> Datums: A __ ; B __ ; C __ (CMM report must reference these)
> Runout / concentricity: feature __ ; relative to datum axis __ ; acceptance after final machining yes/no __
> Machining scope: bores to be finished __ ; honing/reaming yes/no __ ; heat treat stage vs machining __
> Inspection records requested: CMM __ ; air-gauge __ ; roundness/cylindricity __ ; material cert __ ; traceability fields __
> Quantity + schedule: prototype __ ; annual volume __ ; timing __ ; destination + Incoterm __
Submit a structured RFQ (drawing-ready)
Project CTA
Need a Reliable Pump Housing Supplier?
Send your drawing for a structured DFM review, quote scope, and project-specific timing discussion.