Coolant Corrosion may arise from multiple operating, fluid, sampling or analytical causes. The pattern, rate of change and correlated evidence determine the most credible explanation.
Start with the observation
Confirm sample identity, method, units, service interval and historical baseline. A single abnormal parameter rarely confirms root cause, and a plausible explanation should predict other evidence that can be checked.
Differential diagnosis
| Possible cause | Supporting indicators | Confirming tests | Immediate response | Long-term corrective action |
|---|---|---|---|---|
| Low pH | High iron or copper | coolant ph | Follow equipment safety procedure | Correct the confirmed source rather than the isolated number |
| Depleted inhibitors | Rust colour | coolant conductivity | Correct coolant chemistry and source water | Establish a follow-up sampling point and timing |
| Mixed coolant | Deposits | elemental analysis icp oes | Follow equipment safety procedure | Document maintenance so the post-action trend can be evaluated |
| Poor water quality | High iron or copper | coolant ph | Correct coolant chemistry and source water | Correct the confirmed source rather than the isolated number |
Confirming and supporting evidence
Confirming tests
Supporting indicators
- High iron or copper
- Rust colour
- Deposits
Immediate and corrective actions
| Stage | Objective | Action |
|---|---|---|
| 1 · Verify | Confirm the observation is comparable | Check asset, compartment, sample point, units, method, interval, top-up and maintenance history. |
| 2 · Protect | Control immediate equipment or safety risk | Follow equipment safety procedure; Correct coolant chemistry and source water |
| 3 · Diagnose | Find the source using independent evidence | Use coolant ph, coolant conductivity, elemental analysis icp oes and relevant inspection evidence. |
| 4 · Correct and confirm | Remove the cause and prove effectiveness | Correct the confirmed source rather than the isolated number; Establish a follow-up sampling point and timing; Document maintenance so the post-action trend can be evaluated |
- 01Follow equipment safety procedure
- 02Correct coolant chemistry and source water
- 03Correct the confirmed source rather than the isolated number
- 04Establish a follow-up sampling point and timing
- 05Document maintenance so the post-action trend can be evaluated
False positives and context checks
- Non-representative sample
- Changed method or laboratory
- Recent top-up or overhaul
- Container or sampling-tool contamination
References and method context
References identify authoritative source families; they do not reproduce protected procedures or acceptance tables. Verify the current official edition before procedural or conformity use.