How to measure the operating temperature of a sand mill?

I. Commonly used testing tools
1. Infrared thermometer
Key points: Aim at the cylinder surface or gland at a distance of 30-50 cm, avoiding direct sunlight. Measure at multiple points and take the average.
Advantages: Non-contact measurement, suitable for quick inspections, and allows for simultaneous comparison of temperature differences between the two sides.
2. Thermocouple thermometer
Installation requirements: The probe must be close to the friction pair or grinding chamber. Secure it through a pre-drilled hole and fill it with graphite sealant to ensure airtightness.
Application scenarios: Continuous monitoring of temperature fluctuations is required (such as grinding high-viscosity materials). Accuracy can reach ±0.5°C.
3. Thermistor (PT100)
Wiring specifications: Use a three-wire connection to compensate for line resistance. Keep shielded cables away from motor power lines.
Calibration interval: Quarterly calibration using a standard constant temperature oil bath. Replace the probe if the deviation exceeds 0.8°C. II. Testing Process and Standards
1. Temperature Reference Setting
During normal operation, the cylinder surface temperature should be 10-30°C higher than the ambient temperature (e.g., when the ambient temperature is 30°C, a reasonable equipment temperature range of 40-60°C is acceptable).
The mechanical seal friction pair temperature must be ≤70°C, and the rubber seal temperature must be ≤60°C.
2. Dynamic Monitoring Procedures
After startup, record the temperature every 30 minutes, focusing on the peak temperature and fluctuation range.
If the temperature on one side is consistently more than 5°C higher than the other, check the lubrication or sealing condition.
III. Abnormal Handling and Calibration
Overtemperature Alarm: Immediately shut down the machine and check the cooling water flow rate (pressure must be 0.2-0.3 MPa) or the wear of the dispersion disc.
Calibration Requirements: Infrared thermometers must be regularly calibrated with a standard blackbody. Thermocouples must be verified at two points: an ice-water mixture (0°C) and boiling water (100°C).