Suitable temperature rise control range of ZQ350-31.5-III gearbox during trial operation

Temperature rise and temperature control for the ZQ350-31.5-III gear reducer during trial operation shall comply with dual criteria: ambient temperature reference, temperature rise limit and maximum temperature limit. Specific requirements are specified below:

1. Temperature rise limit (core control parameter) (1) No-load trial operation: The housing temperature rise shall be ≤25 ℃, and the bearing region temperature rise shall be ≤30 ℃. Temperature rise is calculated as operating temperature minus ambient temperature. Ambient temperature adopts on-site measured values during trial operation (the standard reference range is normally 20–25 ℃).
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(2) Load trial operation (50%–100% rated load): The housing temperature rise shall be ≤40 ℃, and the bearing part temperature rise shall be ≤45 ℃. After continuous full-load operation for 2 hours, the temperature rise must stay stable with no continuous upward trend.

2. Maximum temperature limit (safety threshold) (1) The maximum housing temperature shall not exceed 80 ℃. Exceeding this value will reduce lubricant viscosity, cause oil film breakdown and aggravate gear meshing wear. (2) The maximum temperature of bearing components shall not exceed 95 ℃. Once over this limit, bearing grease tends to carbonize. Thermal deformation may occur on rollers and raceways, and bearing seizure can happen under severe conditions.
3. Supplementary control requirements (1) Temperature readings shall be logged at multiple time intervals throughout trial operation: at startup, 10 min, 30 min, 60 min and 120 min. If the temperature rise rate exceeds 5 ℃ per 10 minutes, shut down the unit immediately for fault inspection. Potential causes include misalignment during installation, incorrect lubricant quantity or oil grade, and insufficient gear meshing clearance.

(2) When ambient temperature rises above 35 ℃, the trial load shall be appropriately reduced (80% rated load maximum recommended), or forced air cooling shall be implemented to prevent excessive temperature rise.