Machine Design #100: Rotary Shaft Runout — Combined Error Appears When the Machine Runs
MINATA turns the Vietnamese source into an evidence-led guide. rotary shaft runout must preserve function, manufacturability, inspectability, cost, and serviceability when the boundary changes.
Function before a number
Write the input, expected result, acceptance limit, failure symptom, and measurement method before choosing a geometric value, roughness, or fit. Assign an owner to every value and change.
Core checks
- Functional effect of radial and axial runout: record value, source, method, owner, and pass/fail evidence.
- Datum, setup, and indicator direction: record value, source, method, owner, and pass/fail evidence.
- Speed, balance, and combined error: record value, source, method, owner, and pass/fail evidence.
- Bearing, coupling, and assembly contribution: record value, source, method, owner, and pass/fail evidence.
- Measurement repeatability and uncertainty: record value, source, method, owner, and pass/fail evidence.
- Acceptance, correction, and service limit: record value, source, method, owner, and pass/fail evidence.
| Failure mode | Symptom | Verification |
|---|
| Function not defined | Over-tight or weak geometry | Rebuild the functional stack |
| Datum not real | Inspection and assembly disagree | Try the real fixture |
| Documents out of sync | Correct value, wrong revision | Baseline every reference |
1. Review pass: function and load path
Review function and load path for the rotary shaft runout. The key risk is datum, radial and axial runout, speed, balance, bearing, and inspection. Define lower and upper boundaries, the simultaneous worst case, evidence source, owner, and change trigger. Confirm model, drawing, BOM, material, process, inspection, and work instruction use the same revision. Test normal operation, variation, wrong input, interruption, and a controlled fault. Record actual value, unit, condition, instrument or log, sample or serial, pass/fail, and next action.
2. Review pass: datums and relationships
Review datums and relationships for the rotary shaft runout. The key risk is datum, radial and axial runout, speed, balance, bearing, and inspection. Define lower and upper boundaries, the simultaneous worst case, evidence source, owner, and change trigger. Confirm model, drawing, BOM, material, process, inspection, and work instruction use the same revision. Test normal operation, variation, wrong input, interruption, and a controlled fault. Record actual value, unit, condition, instrument or log, sample or serial, pass/fail, and next action.
3. Review pass: process capability
Review process capability for the rotary shaft runout. The key risk is datum, radial and axial runout, speed, balance, bearing, and inspection. Define lower and upper boundaries, the simultaneous worst case, evidence source, owner, and change trigger. Confirm model, drawing, BOM, material, process, inspection, and work instruction use the same revision. Test normal operation, variation, wrong input, interruption, and a controlled fault. Record actual value, unit, condition, instrument or log, sample or serial, pass/fail, and next action.
4. Review pass: assembly and adjustment
Review assembly and adjustment for the rotary shaft runout. The key risk is datum, radial and axial runout, speed, balance, bearing, and inspection. Define lower and upper boundaries, the simultaneous worst case, evidence source, owner, and change trigger. Confirm model, drawing, BOM, material, process, inspection, and work instruction use the same revision. Test normal operation, variation, wrong input, interruption, and a controlled fault. Record actual value, unit, condition, instrument or log, sample or serial, pass/fail, and next action.
5. Review pass: inspection and uncertainty
Review inspection and uncertainty for the rotary shaft runout. The key risk is datum, radial and axial runout, speed, balance, bearing, and inspection. Define lower and upper boundaries, the simultaneous worst case, evidence source, owner, and change trigger. Confirm model, drawing, BOM, material, process, inspection, and work instruction use the same revision. Test normal operation, variation, wrong input, interruption, and a controlled fault. Record actual value, unit, condition, instrument or log, sample or serial, pass/fail, and next action.
6. Review pass: failure and recovery
Review failure and recovery for the rotary shaft runout. The key risk is datum, radial and axial runout, speed, balance, bearing, and inspection. Define lower and upper boundaries, the simultaneous worst case, evidence source, owner, and change trigger. Confirm model, drawing, BOM, material, process, inspection, and work instruction use the same revision. Test normal operation, variation, wrong input, interruption, and a controlled fault. Record actual value, unit, condition, instrument or log, sample or serial, pass/fail, and next action.
7. Review pass: supplier and acceptance
Review supplier and acceptance for the rotary shaft runout. The key risk is datum, radial and axial runout, speed, balance, bearing, and inspection. Define lower and upper boundaries, the simultaneous worst case, evidence source, owner, and change trigger. Confirm model, drawing, BOM, material, process, inspection, and work instruction use the same revision. Test normal operation, variation, wrong input, interruption, and a controlled fault. Record actual value, unit, condition, instrument or log, sample or serial, pass/fail, and next action.
8. Review pass: revision and change
Review revision and change for the rotary shaft runout. The key risk is datum, radial and axial runout, speed, balance, bearing, and inspection. Define lower and upper boundaries, the simultaneous worst case, evidence source, owner, and change trigger. Confirm model, drawing, BOM, material, process, inspection, and work instruction use the same revision. Test normal operation, variation, wrong input, interruption, and a controlled fault. Record actual value, unit, condition, instrument or log, sample or serial, pass/fail, and next action.
9. Review pass: cost and trade-off
Review cost and trade-off for the rotary shaft runout. The key risk is datum, radial and axial runout, speed, balance, bearing, and inspection. Define lower and upper boundaries, the simultaneous worst case, evidence source, owner, and change trigger. Confirm model, drawing, BOM, material, process, inspection, and work instruction use the same revision. Test normal operation, variation, wrong input, interruption, and a controlled fault. Record actual value, unit, condition, instrument or log, sample or serial, pass/fail, and next action.
10. Review pass: safety and misuse
Review safety and misuse for the rotary shaft runout. The key risk is datum, radial and axial runout, speed, balance, bearing, and inspection. Define lower and upper boundaries, the simultaneous worst case, evidence source, owner, and change trigger. Confirm model, drawing, BOM, material, process, inspection, and work instruction use the same revision. Test normal operation, variation, wrong input, interruption, and a controlled fault. Record actual value, unit, condition, instrument or log, sample or serial, pass/fail, and next action.
11. Review pass: data and audit
Review data and audit for the rotary shaft runout. The key risk is datum, radial and axial runout, speed, balance, bearing, and inspection. Define lower and upper boundaries, the simultaneous worst case, evidence source, owner, and change trigger. Confirm model, drawing, BOM, material, process, inspection, and work instruction use the same revision. Test normal operation, variation, wrong input, interruption, and a controlled fault. Record actual value, unit, condition, instrument or log, sample or serial, pass/fail, and next action.
12. Review pass: training
Review training for the rotary shaft runout. The key risk is datum, radial and axial runout, speed, balance, bearing, and inspection. Define lower and upper boundaries, the simultaneous worst case, evidence source, owner, and change trigger. Confirm model, drawing, BOM, material, process, inspection, and work instruction use the same revision. Test normal operation, variation, wrong input, interruption, and a controlled fault. Record actual value, unit, condition, instrument or log, sample or serial, pass/fail, and next action.
13. Review pass: field feedback
Review field feedback for the rotary shaft runout. The key risk is datum, radial and axial runout, speed, balance, bearing, and inspection. Define lower and upper boundaries, the simultaneous worst case, evidence source, owner, and change trigger. Confirm model, drawing, BOM, material, process, inspection, and work instruction use the same revision. Test normal operation, variation, wrong input, interruption, and a controlled fault. Record actual value, unit, condition, instrument or log, sample or serial, pass/fail, and next action.
14. Review pass: final release
Review final release for the rotary shaft runout. The key risk is datum, radial and axial runout, speed, balance, bearing, and inspection. Define lower and upper boundaries, the simultaneous worst case, evidence source, owner, and change trigger. Confirm model, drawing, BOM, material, process, inspection, and work instruction use the same revision. Test normal operation, variation, wrong input, interruption, and a controlled fault. Record actual value, unit, condition, instrument or log, sample or serial, pass/fail, and next action.
15. Review pass: function and load path
Review function and load path for the rotary shaft runout. The key risk is datum, radial and axial runout, speed, balance, bearing, and inspection. Define lower and upper boundaries, the simultaneous worst case, evidence source, owner, and change trigger. Confirm model, drawing, BOM, material, process, inspection, and work instruction use the same revision. Test normal operation, variation, wrong input, interruption, and a controlled fault. Record actual value, unit, condition, instrument or log, sample or serial, pass/fail, and next action.
16. Review pass: datums and relationships
Review datums and relationships for the rotary shaft runout. The key risk is datum, radial and axial runout, speed, balance, bearing, and inspection. Define lower and upper boundaries, the simultaneous worst case, evidence source, owner, and change trigger. Confirm model, drawing, BOM, material, process, inspection, and work instruction use the same revision. Test normal operation, variation, wrong input, interruption, and a controlled fault. Record actual value, unit, condition, instrument or log, sample or serial, pass/fail, and next action.
17. Review pass: process capability
Review process capability for the rotary shaft runout. The key risk is datum, radial and axial runout, speed, balance, bearing, and inspection. Define lower and upper boundaries, the simultaneous worst case, evidence source, owner, and change trigger. Confirm model, drawing, BOM, material, process, inspection, and work instruction use the same revision. Test normal operation, variation, wrong input, interruption, and a controlled fault. Record actual value, unit, condition, instrument or log, sample or serial, pass/fail, and next action.
18. Review pass: assembly and adjustment
Review assembly and adjustment for the rotary shaft runout. The key risk is datum, radial and axial runout, speed, balance, bearing, and inspection. Define lower and upper boundaries, the simultaneous worst case, evidence source, owner, and change trigger. Confirm model, drawing, BOM, material, process, inspection, and work instruction use the same revision. Test normal operation, variation, wrong input, interruption, and a controlled fault. Record actual value, unit, condition, instrument or log, sample or serial, pass/fail, and next action.
19. Review pass: inspection and uncertainty
Review inspection and uncertainty for the rotary shaft runout. The key risk is datum, radial and axial runout, speed, balance, bearing, and inspection. Define lower and upper boundaries, the simultaneous worst case, evidence source, owner, and change trigger. Confirm model, drawing, BOM, material, process, inspection, and work instruction use the same revision. Test normal operation, variation, wrong input, interruption, and a controlled fault. Record actual value, unit, condition, instrument or log, sample or serial, pass/fail, and next action.
20. Review pass: failure and recovery
Review failure and recovery for the rotary shaft runout. The key risk is datum, radial and axial runout, speed, balance, bearing, and inspection. Define lower and upper boundaries, the simultaneous worst case, evidence source, owner, and change trigger. Confirm model, drawing, BOM, material, process, inspection, and work instruction use the same revision. Test normal operation, variation, wrong input, interruption, and a controlled fault. Record actual value, unit, condition, instrument or log, sample or serial, pass/fail, and next action.
21. Review pass: supplier and acceptance
Review supplier and acceptance for the rotary shaft runout. The key risk is datum, radial and axial runout, speed, balance, bearing, and inspection. Define lower and upper boundaries, the simultaneous worst case, evidence source, owner, and change trigger. Confirm model, drawing, BOM, material, process, inspection, and work instruction use the same revision. Test normal operation, variation, wrong input, interruption, and a controlled fault. Record actual value, unit, condition, instrument or log, sample or serial, pass/fail, and next action.
22. Review pass: revision and change
Review revision and change for the rotary shaft runout. The key risk is datum, radial and axial runout, speed, balance, bearing, and inspection. Define lower and upper boundaries, the simultaneous worst case, evidence source, owner, and change trigger. Confirm model, drawing, BOM, material, process, inspection, and work instruction use the same revision. Test normal operation, variation, wrong input, interruption, and a controlled fault. Record actual value, unit, condition, instrument or log, sample or serial, pass/fail, and next action.
23. Review pass: cost and trade-off
Review cost and trade-off for the rotary shaft runout. The key risk is datum, radial and axial runout, speed, balance, bearing, and inspection. Define lower and upper boundaries, the simultaneous worst case, evidence source, owner, and change trigger. Confirm model, drawing, BOM, material, process, inspection, and work instruction use the same revision. Test normal operation, variation, wrong input, interruption, and a controlled fault. Record actual value, unit, condition, instrument or log, sample or serial, pass/fail, and next action.
24. Review pass: safety and misuse
Review safety and misuse for the rotary shaft runout. The key risk is datum, radial and axial runout, speed, balance, bearing, and inspection. Define lower and upper boundaries, the simultaneous worst case, evidence source, owner, and change trigger. Confirm model, drawing, BOM, material, process, inspection, and work instruction use the same revision. Test normal operation, variation, wrong input, interruption, and a controlled fault. Record actual value, unit, condition, instrument or log, sample or serial, pass/fail, and next action.
25. Review pass: data and audit
Review data and audit for the rotary shaft runout. The key risk is datum, radial and axial runout, speed, balance, bearing, and inspection. Define lower and upper boundaries, the simultaneous worst case, evidence source, owner, and change trigger. Confirm model, drawing, BOM, material, process, inspection, and work instruction use the same revision. Test normal operation, variation, wrong input, interruption, and a controlled fault. Record actual value, unit, condition, instrument or log, sample or serial, pass/fail, and next action.
26. Review pass: training
Review training for the rotary shaft runout. The key risk is datum, radial and axial runout, speed, balance, bearing, and inspection. Define lower and upper boundaries, the simultaneous worst case, evidence source, owner, and change trigger. Confirm model, drawing, BOM, material, process, inspection, and work instruction use the same revision. Test normal operation, variation, wrong input, interruption, and a controlled fault. Record actual value, unit, condition, instrument or log, sample or serial, pass/fail, and next action.
27. Review pass: field feedback
Review field feedback for the rotary shaft runout. The key risk is datum, radial and axial runout, speed, balance, bearing, and inspection. Define lower and upper boundaries, the simultaneous worst case, evidence source, owner, and change trigger. Confirm model, drawing, BOM, material, process, inspection, and work instruction use the same revision. Test normal operation, variation, wrong input, interruption, and a controlled fault. Record actual value, unit, condition, instrument or log, sample or serial, pass/fail, and next action.
28. Review pass: final release
Review final release for the rotary shaft runout. The key risk is datum, radial and axial runout, speed, balance, bearing, and inspection. Define lower and upper boundaries, the simultaneous worst case, evidence source, owner, and change trigger. Confirm model, drawing, BOM, material, process, inspection, and work instruction use the same revision. Test normal operation, variation, wrong input, interruption, and a controlled fault. Record actual value, unit, condition, instrument or log, sample or serial, pass/fail, and next action.
MINATA release checklist
- [ ] Function, boundary, and failure symptom are written.
- [ ] Datums, ownership, process, and mistake-proofing are clear.
- [ ] Six topic checks have evidence and pass/fail limits.
- [ ] Manufacturing, assembly, inspection, and maintenance were tried.
- [ ] Revision, supplier, material, and configuration records agree.
Good engineering is an explicit chain that survives manufacture, operation, maintenance, and change. For rotary shaft runout, evidence that geometry and function remain reliable is the MINATA standard.
Public references
- MINATA Q-up design practice and internal review checklist.
- Applicable geometric, material, surface, or quality standard selected by the project owner.
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