Common faults of lifting bell jar furnace

The common faults of the lifting bell jar furnace can be classified into five categories: electrical faults, mechanical faults, temperature control faults, atmosphere control faults, and sealing faults. The specific manifestations and solutions are as follows:

1. Electrical malfunction
Power Problem
Phenomenon: The device cannot start and there is no display on the touch screen.
Reason: Poor contact of power cord, power switch not turned on, or blown fuse.
Solution: Check the power cord connection, confirm the switch status, and replace the fuse.
Heating element malfunction
Phenomenon: There is no reaction or slow heating at the furnace temperature.
Reason: Heating elements (such as silicon carbon rods, silicon molybdenum rods) are broken, aged, or internally short circuited.
Solution: Replace broken or aged heating elements and check if the insulation layer is damaged.
Controllable silicon fault
Phenomenon: The device trips or burns out the fuse.
Reason: thyristor breakdown or overload operation.
Solution: Replace the thyristor components and check if the load exceeds the limit.

2. Mechanical malfunction
Fault in lifting structure
Phenomenon: The lifting kiln truck is not lifted in place or stuck.
Reason: Overload of the lifting motor, improper or damaged position of the travel switch.
Solution: Check the motor air circuit breaker thermal overload switch, adjust or replace the travel switch.
Wear of transmission components
Phenomenon: Abnormal noise or shaking occurs during the lifting process.
Reason: Wear or insufficient lubrication of transmission components such as chains and gears.
Solution: Replace worn parts and replenish lubricating oil.

3. Temperature control malfunction
Excessive temperature fluctuations
Phenomenon: The furnace temperature fluctuates and cannot be stabilized.
Reason: Heating element aging, control system malfunction (such as improper PID parameter adjustment), or poor thermocouple contact.
Solution: Replace the heating element, readjust the PID parameters, and check the thermocouple wiring.
Over-temperature alarm
Phenomenon: Touch screen displays over limit temperature trip protection.
Reason: The extreme protection temperature setting in the system configuration is incorrect or the thermocouple is disconnected.
Solution: Reset the limit protection temperature and check if the thermocouple is damaged.

4. Atmosphere control malfunction
Unstable gas flow rate
Phenomenon: The traffic fluctuates between high and low, or there is no display.
Reason: Insufficient gas source pressure, malfunction of mass flow controller, or pipeline blockage.
Solution: Check the air source pressure, replace the mass flow controller, and clear the pipeline.
The atmosphere control fluctuates greatly
Phenomenon: The composition of the atmosphere inside the furnace is unstable.
Reason: Improper adjustment of PID parameters in the atmosphere controller or incorrect gas mixing ratio.
Solution: Reset the PID parameters and adjust the gas mixing ratio.

5. Sealing failure
Furnace body leakage
Phenomenon: The pressure inside the furnace cannot be maintained, resulting in oxidation or pollution.
Reason: Leakage of pipeline valves, aging of kiln car seals, or leakage of protective covers around the furnace body.
Solution: Replace the leaking valve or sealing strip, and tighten the screws of the protective cover.
Circulating fan leaks air
Phenomenon: There is gas leakage at the fan.
Reason: Severe wear of graphite packing or deformation of motor shaft.
Solution: Replace the graphite packing or repair the motor shaft.