A356-T6 Pressure-Tight Pump Housing RFQ Checklist: Leak Test, Bearing Seats, Datums, Machining, and Inspection Evidence

# A356-T6 Pressure-Tight Pump Housing RFQ Checklist: Leak Test, Bearing Seats, Datums, Machining, and Inspection Evidence

Pressure-tight pump housing RFQs often fail for a simple reason: the buyer asks for "A356-T6 pump housing" or "leak test required," but the quote does not define the leak-test method, bearing-seat datums, machining sequence, or inspection records. Suppliers then quote different assumptions, and the difference only becomes visible at sample approval.

This checklist is written for OEM procurement, SQE, and engineering teams preparing a drawing-ready RFQ for an A356-T6 pump housing, pump casing, or fluid-system housing. The goal is not to promise a generic leak result. The goal is to make the technical and commercial assumptions clear enough for a supplier to quote the real scope.

Useful Bohua routes:

• •Pump housing manufacturer page
• •A356 aluminum casting manufacturer
• •Leak-tight aluminum casting route
• •Pump housing OEM quote route
• •A356-T6 pressure-tight pump housing RFQ route
• •Structured RFQ upload

1) Define the pressure or leak-test requirement first

"Pressure-tight" must become a measurable requirement before quotation. In the RFQ, state:

• •test medium: air, water, oil, helium, or buyer-defined equivalent
• •test pressure and hold time
• •acceptable pressure drop or leak rate
• •sampling plan: prototype only, first article, production sampling, or 100% if required by the buyer
• •whether impregnation is allowed, prohibited, or supplier-proposed only with disclosure
• •whether the test is for raw casting, machined casting, or final assembly state

If your team does not yet know the right test condition, ask suppliers to propose the method and list it as a quote assumption. Do not let the quote hide the test method behind the phrase "leak test included."

2) Connect leak risk to machining exposure

Many pump housings look acceptable as castings but fail after machining opens porosity near sealing faces, ports, or bearing bores. Your RFQ should identify which surfaces become functional after CNC:

• •gasket faces and cover faces
• •shaft seal bores and seal lands
• •bearing seats and pilot bores
• •threaded ports, hydraulic ports, or coolant passages
• •impeller cavity or internal flow surfaces

For each feature, state whether the supplier should quote raw casting only or casting plus CNC machining. A finished pump housing quote should separate casting, machining, leak testing, CMM, and any finishing or coating assumptions.

3) A356-T6: make heat treatment and distortion visible

A356-T6 may be a practical route when the drawing needs a heat-treatable aluminum alloy and the part has pressure, strength, or machining requirements. But T6 also affects distortion risk and machining sequence.

Ask the supplier to state:

• •alloy standard and whether equivalents are allowed
• •heat-treatment stage relative to rough and finish machining
• •whether straightening is expected or prohibited
• •how bearing seats, seal bores, and gasket faces are controlled after heat treatment
• •which records are included: material certificate, heat-treatment record, hardness or mechanical-property evidence if required

If the buyer's drawing fixes A356-T6, quote that requirement directly. If the drawing allows alternatives, ask suppliers to explain the tradeoff rather than switching alloy silently.

4) Bearing seats and datums: do not quote them as generic bores

Pump housings can fail from shaft misalignment, bearing-seat runout, seal wear, vibration, and assembly stack issues. In the RFQ, define:

• •primary, secondary, and tertiary datums
• •which bearing seats or seal bores reference those datums
• •runout, concentricity, or positional requirements if defined
• •measurement method or supplier-proposed method
• •whether the final CMM report must reference the buyer's datum scheme

If the drawing is not final, attach a marked PDF showing which bores, faces, and mounting surfaces are function-critical. Even a simple critical-feature map reduces quoting ambiguity.

5) Inspection evidence that should be quoted upfront

For a pressure-tight A356-T6 pump housing, request only the records that match the real approval risk:

• •material certificate
• •heat-treatment record when T6 is required
• •CMM report for datums, bearing seats, sealing faces, and critical hole patterns
• •leak-test or pressure-test record with method, pressure, hold time, and sampling plan
• •surface finish record for sealing faces if specified
• •FAI or PPAP-style evidence only when your approval plan requires it

Do not rely on broad terms such as "high quality" or "leak-risk-controlled." Ask for the records the buyer will actually use to approve the sample and release production.

Copy-paste RFQ starter

> A356-T6 pressure-tight pump housing RFQ (copy-paste)

> Files: 2D PDF rev __ ; STEP __

> Part use: pump housing / pump casing / fluid-system housing __

> Alloy + temper: A356-T6 required yes/no __ ; equivalents allowed yes/no __

> Leak or pressure test: medium __ ; pressure __ ; hold time __ ; acceptance criterion __ ; sampling plan __

> Impregnation: allowed/prohibited/supplier proposal with disclosure __

> Functional features: bearing seats __ ; seal bores __ ; gasket faces __ ; ports/threads __

> Datums: A __ ; B __ ; C __ ; CMM report must reference these yes/no __

> Machining scope: raw casting only / casting plus CNC / final machining included __

> Inspection records requested: material cert __ ; heat treatment record __ ; CMM __ ; leak-test record __ ; FAI/PPAP if required __

> Quantity + schedule: prototype __ ; annual volume __ ; destination + Incoterm __

Submit a drawing-ready RFQ

Use the A356 route when alloy, heat treatment, pressure, machining, and inspection evidence are central to supplier selection.

• •Review Bohua's A356 casting page
• •Compare pressure-tight casting assumptions
• •Open the A356-T6 pump housing quote route
• •Upload drawings through Request Quote