Working principle and usage details of electric blast drying oven

1、 Working principle

Electric hot air drying oven is a device that uses electric heating elements to heat and forcefully circulate air for efficient drying. It is widely used in laboratories, pharmaceuticals, food, chemical industry and other fields. Its core working principle can be divided into the following parts:

1. Heating system

-Using electric heating tubes or far-infrared heating elements as heat sources, the air inside the box is directly heated by converting electrical energy into thermal energy.

-The heating power can be adjusted according to demand, usually equipped with multiple switches or PID temperature control systems to achieve precise temperature control.

2. Blowing circulation system

-Equipped with a centrifugal fan, the heated air is forced to circulate through convection, ensuring even temperature distribution inside the box.

-Air duct design optimizes the airflow path to avoid dead corners and ensure consistent heating of the sample.

3. Temperature control system

-Mechanical or electronic temperature controllers (such as PID controllers) monitor the temperature inside the box in real time and maintain the set value by adjusting the heating power.

-The temperature fluctuation range is usually controlled within ± 1 ℃, and some high-precision models can reach ± 0.5 ℃.

4. Structural equipment

-The box adopts a double-layer steel structure, with insulation materials (such as fiberglass or polyurethane) filled in the middle to reduce heat loss.

-The door is equipped with high-temperature resistant sealing strips to prevent heat leakage and ensure airtightness.

Workflow: After power on, the electric heating element heats the air → the fan blows the hot air into the box → the temperature controller monitors the temperature and adjusts the heating → the circulating air makes the temperature uniform → the sample is dried at a constant temperature.

2、 Details of use

1. Preparation before use

-Cleaning and inspection: Wipe the inside and outside of the box with a dry cloth to remove debris; Check if the electric heating element, fan, and sealing strip are functioning properly.

-Sample placement:

-The samples should be evenly placed, not exceeding 2/3 of the shelf area, to avoid blocking the air duct.

-Liquid samples should be stored in sealed containers to prevent volatile contamination of the container or the risk of fire.

-High temperature flammable materials (such as ethanol) need to be dried in the low temperature range and ventilation should be strengthened.

2. Parameter settings

-Temperature setting: Select the temperature based on the characteristics of the sample (such as moisture drying at 100-120 ℃, sterilization of biological culture medium at 160-180 ℃).

-Time setting: Based on the sample size and humidity adjustment, it is recommended to conduct a short-term test first and then extend it.

-Attention:

-After use or long-term disuse, the empty container needs to be preheated for 10 minutes to remove moisture.

-The temperature should not rise or fall suddenly to avoid deformation of the box or breakage of the glass observation window.

3. Monitoring during operation

-Observe the status of the sample through the glass observation window and avoid frequent door opening (temperature fluctuations inside the box take 10-15 minutes to recover with each opening).

-If there is a burnt smell or smoke, immediately turn off the power and check if the sample is overheated.

4. Maintenance after use

-Cleaning: After the box has cooled down to room temperature, clean the residue and debris, and wipe the inner wall with a damp cloth (do not rinse electrical components).

-Heat dissipation: Natural cooling after turning off the power to avoid aging of the sealing strip caused by immediately closing the cover.

-Regular inspection:

-Check monthly whether the electric heating tube is oxidized and whether the fan bearings are lacking in oil (apply a small amount of high-temperature grease).

-Calibrate the thermostat annually and replace aging seals.

4、 Safety precautions

1. Anti scald protection: Wear insulated gloves during operation to avoid contact with the surface of the high-temperature box.

2. Explosion proof risk: Drying of volatile solvents should be carried out in a fume hood, and closed heating is strictly prohibited.

3. Electrical safety: Grounding must be reliable and avoid use in humid environments; Long term non use requires unplugging the power supply.

4. Emergency handling: In case of sudden power outage, immediately open the box door to dissipate heat and prevent excessive baking of the samples.