Precautions for operating a box type atmosphere annealing furnace

The box type atmosphere annealing furnace improves the performance of metal materials by precisely controlling the temperature and atmosphere environment for heat treatment. During the operation process, it is necessary to strictly follow safety regulations and technical requirements. The following details the precautions from four dimensions: pre operation preparation, operation process control, safety protection, and maintenance:

1. Preparation before operation
Equipment inspection
Electrical system: Check whether the power lines, control cabinet, and heating elements are intact to avoid the risk of short circuit or leakage.
Mechanical components: Confirm that the sealing strip of the furnace door is not aging, the furnace door opens and closes smoothly, and the transmission mechanism (such as chains and gears) is well lubricated.
Gas system: Check whether the gas pipelines, valves, and flow meters are sealed and free of leaks; Ensure that the pressure of the gas storage container is normal.
Temperature control system: calibrate the temperature sensor to ensure that the displayed value is consistent with the actual temperature; Check if the over temperature alarm device is sensitive.
material preparation
Workpiece cleaning: The workpiece to be processed needs to be cleaned of oil and rust to avoid contaminating the atmosphere inside the furnace.
Furnace loading method: The workpieces should be evenly placed in the furnace to avoid stacking too densely and affecting the circulation of the atmosphere; Use heat-resistant trays or brackets to fix the workpiece.
Parameter setting
Temperature curve: Set the heating rate, insulation temperature and time, and cooling rate according to the material type and process requirements.
Atmosphere parameters: Select the appropriate atmosphere type (such as nitrogen, hydrogen, argon, etc.), set the gas flow rate and pressure.

2. Process control during operation
Heating stage
Slow heating: Avoid rapid heating that may cause cracking or deformation of the workpiece, especially for materials such as high alloy steel and titanium alloy.
Atmosphere replacement: Before heating up, a protective gas should be introduced to eliminate the air inside the furnace and prevent oxidation of the workpiece.
Insulation stage
Temperature stability: Monitor temperature fluctuations inside the furnace to ensure they are within ± 5 ℃ range.
Atmosphere monitoring: Regularly check gas flow and pressure to ensure stable atmosphere composition; Use an oxygen probe or dew point meter to monitor the purity of the atmosphere.
Cooling stage
Control cooling rate: Avoid excessive cooling that can cause an increase in internal stress in the workpiece, especially for workpieces that have been quenched and tempered.
Atmosphere protection: During the cooling process, continue to introduce protective gas to prevent the workpiece from oxidizing at high temperatures.

3. Security protection
Personal protection
Wear protective equipment: Operators need to wear heat-resistant gloves, protective goggles, thermal insulation clothing, etc.
Avoid direct contact: When the furnace door is open, high-temperature steam and gas may spray out, and a safe distance should be maintained.
Equipment safety
Overtemperature alarm: If the temperature exceeds the set value, the equipment should automatically cut off the heating power and sound an alarm.
Gas leak detection: Install a gas leak alarm device. Once a leak is detected, immediately cut off the gas source and ventilate.
Emergency stop: The control panel should be equipped with an emergency stop button, which can immediately stop the operation of the equipment in case of abnormal situations.
Fire and explosion prevention
Keep away from flammable materials: Flammable and explosive materials should not be stacked around the furnace body.
Safe use of hydrogen: Hydrogen is a flammable and explosive gas, and it is necessary to ensure that the gas path is sealed to avoid mixing with air to form explosive gases.

4. Maintenance and upkeep
Routine maintenance
Cleaning the furnace: Clean the residue and oxides inside the furnace after each use to avoid contaminating subsequent workpieces.
Check sealing: Regularly inspect the furnace door sealing strip and gas path interface to ensure no leakage.
Regular maintenance
Heating element: Check whether the heating wire is aging or broken, and replace it if necessary.
Temperature control system: Calibrate temperature sensors and controllers to ensure temperature control accuracy.
Gas system: Clean the gas filter, check whether the flow meter and valve are sensitive.
Long term disuse treatment
Exhaust gas: Before long-term shutdown, exhaust the gas in the furnace to avoid residual gas corroding the equipment.
Moisture and rust prevention: Place desiccants in the furnace to prevent equipment from getting damp and rusting.

5. Summary
The operation of the box type atmosphere annealing furnace must strictly follow the following principles:
Safety first: Ensure the safety of equipment, personnel, and the environment, and avoid accidents such as fires, explosions, and poisoning.
Precise control: Accurately set temperature, atmosphere, and time parameters to ensure that the workpiece performance meets standards.
Standardized maintenance: Regularly inspect and maintain equipment to extend its service life and reduce failure rates.

By standardizing operations and scientific management, the advantages of box type atmosphere annealing furnaces can be fully utilized to improve the quality of metal material heat treatment and create greater economic benefits for enterprises.