Common faults and solutions of vertical fluidized bed tube furnace

The common faults and solutions of vertical fluidized bed tube furnace are as follows:

1. Electrical and control system malfunction
Abnormal power supply and instrument display
Phenomenon: There is no power display on the instrument after power on, or the instrument is normal but the heating element is not working.
Possible reasons: unplugged plug, blown fuse, blown control circuit fuse, broken heating element, control circuit malfunction.
resolvent:
Check if the plug is properly inserted and replace the fuse or fuse.
Open the furnace door and check if the heating element is broken. If it is broken, it needs to be replaced.
Notify professional maintenance personnel to repair the control circuit.
Temperature control malfunction
Phenomenon: The temperature inside the furnace does not rise or the temperature display does not match the actual situation.
Possible reasons: set temperature too low, damaged control circuit, damaged temperature sensor or temperature controller, deviation between temperature measurement point and layout point position.
resolvent:
Adjust the set temperature to the desired value.
Notify professional maintenance personnel to inspect and control the circuit.
Replace the temperature sensor or temperature controller.
Set the layout position correctly to ensure accurate temperature measurement.
Over temperature alarm
Phenomenon: The instrument SV alternately displays HIAL, and the temperature inside the furnace exceeds the limit value.
Possible reason: The temperature inside the furnace is too high, and the instrument serves as a protective measure.
Solution: After the temperature drops to a safe level, the instrument will return to normal. Check the temperature control system to ensure that the parameter settings are correct.

2. Heating system malfunction
Heating element malfunction
Phenomenon: The heating tube does not work, and the temperature inside the furnace cannot rise.
Possible reasons: The heating tube is burnt out and the wiring is disconnected.
resolvent:
Replace the burnt heating tube.
Re fix or replace loose wiring.
Abnormal heating rate
Phenomenon: Slow heating or large temperature fluctuations.
Possible reasons: poor electrical connections, aging heating elements, and suboptimal PID parameters.
resolvent:
Check the electrical connections of the temperature control system to ensure good contact.
Replace the aging heating element.
Adjust PID parameters through self-tuning function to optimize heating rate.

3. Gas and vacuum system malfunction
Reduced vacuum
Phenomenon: Insufficient vacuum degree was found during the use of vacuum pumping.
Possible reasons: Aging of temperature resistant silicone rings between stainless steel flanges and leakage in the vacuum system.
Solution: Replace the heat-resistant silicone ring, reinstall the stainless steel flange, or replace and repair the vacuum system.
Gas leakage
Phenomenon: Leakage of gas in the furnace body leads to unstable atmosphere inside the furnace.
Possible reasons: damage to the kiln shell, poor sealing of the kiln door, and air leakage at the pipe joints.
resolvent:
Check if there is any damage to the kiln shell, and repair or replace it if necessary.
Check if the kiln door seal is good, and replace the sealing material if necessary.
Check if the pipe joints are loose or poorly sealed, and if necessary, re fix or replace them.

4. Fluidization and mechanical failure
Poor fluidization quality
Phenomenon: Gully flow or surging, uneven mixing of particles.
Possible reasons: blockage or improper porosity of the gas distribution plate, uneven particle size distribution.
resolvent:
Clean or replace the gas distribution board.
Adjust the particle size distribution to ensure D10/D90<3.
Furnace cracking
Phenomenon: Cracks or damage appear in the furnace.
Possible reasons: Failure to bake after first use or prolonged disuse, and furnace temperature exceeding the rated temperature.
Solution: After the first use or long-term disuse, heat the tube furnace at around 120 ℃ for 1 hour, then heat it to around 300 ℃ for 2 hours before use. Avoid the furnace temperature exceeding the rated temperature.
Wear and tear of mechanical components
Phenomenon: Wear of gas distribution plate and rupture of furnace tube.
Possible reasons: Long term high temperature operation, gas entrainment particle impact.
Solution: Regularly check the status of the gas distribution plate and furnace tube, and replace worn parts in a timely manner. Install baffles or increase the curvature radius at the bend of the furnace tube to reduce particle deposition.