Start from the characteristics that matter
A casting inspection plan states what is checked, how, how often and which result is acceptable. Build it around the finished drawing and the service requirements before sample production. Begin with the features that control fit, sealing, motion, load and appearance, and give each critical characteristic a drawing reference. "Inspect everything" without a method, sample size or record is not a plan.
A planning structure for each characteristic
Planning structure only; the examples are not a completed test report.
| Field | What to specify | Example |
|---|---|---|
| Characteristic | Drawing identifier | Bearing bore, sealing face, alloy composition, leak rate |
| Requirement | Drawing limit or referenced specification | Size and position to the datum scheme |
| Method | Agreed measurement or test procedure | CMM program, spectrometer, helium sniffer |
| Stage | Where in the route it is checked | Incoming ingot, first sample, after machining, final release |
| Frequency | How often | First article, per lot, every part |
| Record | The evidence | Report tied to part revision and lot or serial |
| Response | What happens on a failure | Containment and approval path |
Casting dimensional inspection
Dimensional inspection checks geometry against the drawing. State cast-blank and machined tolerances separately: the as-cast blank is held to its casting tolerance, machined features to theirs. Agree the inspection datums during tooling so the fixture datum and the CMM datum are the same; a part measured from different datums can pass in one lab and fail in the next. We measure critical dimensions on a fully automatic CMM and 2D features on a video measuring system.
Casting tolerance chart, ISO 8062
First samples vs routine production
First-sample approval establishes whether the route can deliver the agreed component. Routine inspection monitors the released process against selected requirements. Specify the reports and tests for each stage; the full first-article package is not repeated for every shipment unless agreed.
| Check | First article | Routine |
|---|---|---|
| Dimensions | Full layout of every drawing characteristic | Critical characteristics at the agreed frequency |
| Material | Composition and mechanical tests per specification | Composition per melt; mechanicals as agreed |
| Internal soundness | X-ray of the agreed zones | Sampling per lot, if required |
| Leak | Test to the drawing criterion | 100% or sampled, as agreed |
Match the method to the question
Dimensional measurement checks geometry. Material analysis supports alloy verification. Mechanical testing needs a defined specimen and condition. Internal soundness and leak-tightness each need their own criteria. Choose the tests the part needs, and agree the scope with the quotation.
Keep results traceable
Each result is tied to part number, drawing revision, sample or lot identification, requirement, actual result and disposition. Define who reviews the results and which approval releases production. When a drawing or process changes, decide which checks are repeated before the change is released.
Agree the response to a failed check
Define how affected parts are identified and held, who is informed and how a disposition is approved. Rework or a concession must not silently change the product requirement: record the revised instruction or approval and verify the affected characteristics before release.
Questions for supplier qualification
- Which measurements are performed at the supplying site?
- Which calibration records are relevant to the project?
- Which tests or documents are quoted separately?
- How are drawing changes and inspection revisions connected?
Inspection and leak testing PPAP and first article Casting lot release
Example plan for a sealed, machined housing
An illustration of how the planning fields fill in for one part type. Limits and frequencies come from your drawing and are agreed with the quotation; the rows are not a report.
| Characteristic | Method | Stage | Frequency |
|---|---|---|---|
| Alloy composition | Optical emission spectrometer on incoming ingot and melt | Before pouring | Per melt |
| Bearing bore size, form and position | Fully automatic CMM, from the agreed datums | After machining | First article: full; production: as agreed |
| Sealing-face profile and 2D features | Video measuring system | After machining | As agreed |
| Internal soundness in critical zones | X-ray of the agreed regions | First samples; production if required | Sampling per lot |
| Leak-tightness | Helium sniffer, or water immersion to locate leaks | After final machining | 100% or sampled, as agreed |
| Hardness after T6 | Hardness tester at the agreed location | After heat treatment | Per heat-treat batch, if specified |
| Tensile properties | Tensile testing machine on the named specimen | First samples; production as agreed | As agreed |
Which in-house equipment answers which question
| Question on the drawing | Equipment | Note |
|---|---|---|
| Is the geometry inside the limits? | Fully automatic CMM, video measuring system, calipers and gauges | Fixture datum and CMM datum agreed during tooling |
| Is it the right alloy? | Optical emission spectrometer | Ingot checked before melting, melt verified |
| Does it meet the property minimums? | Tensile testing machine, hardness tester | Specimen type and location named in the order |
| Is it sound inside? | X-ray inspection | Zones and acceptance level agreed before first samples |
| Does it leak? | Helium leak detection (sniffer), water immersion tank | Medium, pressure, leak rate and stage stated per part |
Factory visits or live video audits of the inspection area can be arranged during supplier qualification. Inspection and leak testing · Porosity acceptance criteria · Helium leak testing · RFQ checklist