Daily maintenance of well type crucible furnace

The daily maintenance of a well type crucible furnace is crucial to ensuring efficient operation of the equipment, extending its service life, and ensuring production safety. The following provides a systematic maintenance guide from five dimensions: daily cleaning, equipment inspection, lubrication maintenance, safety protection, and regular calibration and recording:

1. Daily cleaning and pollution prevention
Furnace cleaning
Frequency: After processing each batch or once a week (depending on usage frequency).
method:
After the furnace cools to room temperature, use a dust-free cloth or vacuum cleaner to remove residual powder, slag, or oxides.
Avoid using metal tools to scrape the inner wall of the furnace to prevent damage to refractory materials.
Example: After processing metal powder, it is necessary to thoroughly clean the sediment at the bottom of the furnace to prevent impurities from being generated during the next heating.
Crucible maintenance
Inspection: Check the crucible for cracks, deformation, or corrosion after each use.
Replacement: When the graphite crucible shows obvious wear or thickness reduction of more than 20%, it needs to be replaced; Ceramic crucibles with cracks need to be stopped immediately.
Storage: Unused crucibles should be stored in a dry, non corrosive gas environment.
Seals and interfaces
Cleaning: Regularly clean the dust or residue on the furnace door sealing ring and gas inlet and outlet.
Replacement: When the sealing ring ages or deforms, it needs to be replaced to ensure the sealing performance of the furnace (leakage rate ≤ 1 × 10 ⁻³ Pa · m ³/s).

2. Equipment inspection and preventive maintenance
Electrical system inspection
Wiring: Check the power cord and heating element wiring for looseness or aging every month to avoid short circuits or poor contact.
Insulation: Use a megohmmeter to measure the insulation resistance of the heating element (should be ≥ 1 M Ω) to ensure safety.
Temperature controller: Calibrate the temperature controller once every quarter, and the error should be controlled within ± 1 ℃.
Mechanical component inspection
Lifting mechanism: lubricate the lifting screw and guide rail every month, and check whether the motor runs smoothly.
Furnace door: Adjust the furnace door hinge or hydraulic device to ensure smooth opening and closing and good sealing.
Conveyor car: Check whether the track of the conveyor car is clean and whether the wheels rotate flexibly.
Cooling system maintenance
Water quality: Regularly replace the cooling water (deionized water is recommended) to prevent scale from blocking the pipeline.
Flow rate: Check the cooling water flow rate (should be ≥ 5 L/min) to ensure that the heating elements and furnace body are fully cooled.
Leakage: Check if there is any leakage at the water pipe connection and replace the sealing components in a timely manner.

3. Lubrication and anti jamming
Lubrication point
Lift screw: Apply high-temperature grease (such as molybdenum disulfide grease) every month.
Furnace door hinge: Add mechanical oil every quarter to reduce friction.
Conveyor car bearings: Replace lubricating grease every six months to prevent rusting.
Anti jamming measures
When not in use for a long time, lower the lifting mechanism to the lowest position to avoid long-term deformation of the screw under stress.
Regularly manually operate the furnace door and conveyor to prevent mechanical components from rusting.

4. Safety protection and emergency response
Safety device inspection
Overtemperature alarm: Test the overtemperature protection device every month to ensure that it automatically shuts off when the temperature exceeds the set value.
Leakage protection: Check the leakage protector every quarter, and the operating current should be ≤ 30 mA.
Gas alarm: Install oxygen or combustible gas alarm to automatically cut off the gas source when the concentration exceeds the standard.
Emergency Management
Leakage: When gas leakage is detected, immediately turn off the gas source, ventilate and exhaust, and prohibit open flames.
Overtemperature: When the overtemperature alarm is triggered, immediately stop heating and check the temperature control system after the furnace cools down.
Fire: Equip fire extinguishers (such as dry powder or carbon dioxide fire extinguishers) and prohibit using water to extinguish fires.

5. Regular calibration and recording
calibration cycle
Temperature sensor: calibrated every six months, compared with a standard thermometer (error ≤± 2 ℃).
Vacuum gauge: sent for inspection annually to ensure accurate measurement of vacuum degree.
Gas flowmeter: calibrated quarterly, with a flow error of ≤± 5%.
Maintain records
Establish an “Equipment Maintenance Log” to record the time, content, replacement of parts, and abnormal situations of each maintenance.

6. Long term disuse and storage
Pre processing before discontinuation
Clean the furnace, crucible, and conveyor to remove any residue.
Turn off the power, gas, and water sources, and drain the cooling water.
Place desiccants (such as silica gel) in the furnace to prevent moisture.
Sealing environment
The equipment should be stored indoors in a dry, ventilated, and non corrosive gas environment.
Regularly (monthly) check the equipment status to prevent component corrosion or damage.

Summarize
The daily maintenance of the well crucible furnace should follow the principle of “prevention first, regular maintenance”, and ensure stable equipment performance through five steps: cleaning, inspection, lubrication, safety protection, and recording. It is recommended to develop an Equipment Maintenance Manual, clarify responsible personnel and operating standards, and regularly train operators to enhance maintenance awareness.

Key points:
Furnace cleaning and crucible inspection are the core of preventing pollution;
Regular inspection of electrical and cooling systems is a guarantee for safe operation;
Maintaining records and calibration are the basis for tracing problems and optimizing processes.