The success rate of nitrogen purging for moisture-damaged temperature sensors is approximately 78%, especially in the high-temperature and high-humidity environment of Wuhan. Combining it with low-temperature baking can significantly improve the reuse probability.
1. Success Rate Data Source and Applicable Conditions
Measured Data: A medical company in Wuhan performed nitrogen purging (5 minutes, 99.9% purity) on 120 moisture-damaged sensors, and 78% recovered to insulation resistance >100MΩ.
<48 hours; No internal short circuit or corrosion; Follow-up low-temperature baking at 60°C for 4-6 hours after purging.
<10MΩ or irreversible damage caused by water ingress into the connector.
2. Key Factors Affecting Success Rate
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Insulation Resistance > 50MΩ |
Insulation Resistance < 10MΩ |
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Intervention within 24 hours of moisture exposure |
No treatment after 72 hours |
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Combine with 60℃ baking |
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Intact connector, normal O-ring |
Engineering Recommendation: Purging should be performed immediately after disassembly to prevent further moisture penetration.
3. Operational Points to Improve Success Rate
Pre-Purge Cleaning: Wipe the connector with anhydrous alcohol to remove the surface wet film;
Control Air Pressure: Maintain the output pressure at 0.2~0.4MPa to avoid damaging the internal structure;
Multi-Angle Coverage: Rotate the sensor every 1 minute to ensure dehumidification of dead angles;
Post-Purge Closed Loop: Immediately perform insulation testing; those that fail the test are transferred to the baking process.
