Working Principle of Electric Heating Rotary Furnace

Electrically Heated Rotating Oven: Structure and Working Process

 

An electrically heated rotating oven is mainly composed of four core components: heating system, rotation system, hot air circulation system, and control system.

 

Heating System

 

● Heat Source: Built-in electric heating tubes (usually installed on the top, bottom, or both sides of the furnace chamber). When energized, the electric heating tubes directly convert electrical energy into thermal energy to provide heat for the oven interior.

 

● Advantages: Fast heating startup, precise temperature control, no combustion exhaust gases, and eco-friendliness.

 

Rotation System

 

This is the "soul" of a "rotating oven".

 

● Structure: The oven is equipped with a rotating rack (rotary basket) that operates at a constant speed, and baking trays are placed on this basket.

 

● Drive Mechanism: A motor, reducer, and transmission mechanism drive the rotary basket to rotate 360 degrees at a uniform speed.

 

● Purposes:

 

- Ensure uniform heating of products: During rotation, each tray of products in the oven passes through areas with slightly different temperatures (e.g., near the oven door or wall) in sequence, ensuring that all products receive exactly the same total heat throughout the baking process.

 

- Prevent uneven browning: For certain products, rotation avoids local over-browning on the top or one side caused by prolonged exposure to the heat source.

 

Hot Air Circulation System

 

● Structure: High-temperature-resistant fans are installed inside the oven to force the hot air inside to circulate.

 

● Purposes:

 

- Create a uniform temperature field: The fans agitate the hot air, making the temperature highly uniform in all parts of the oven and eliminating the common "hot spots" and "cold spots" in static ovens.

 

- Improve thermal efficiency: Flowing hot air transfers heat to food more quickly and effectively, shortening the baking time.

 

- Remove surface moisture: Helps the product surface develop color and form a crispy crust.

 

Control System

 

● Core Component: Typically uses a microcomputer-based PLC (Programmable Logic Controller) or intelligent temperature control meters.

 

● Functions:

 

- Precise temperature control: Independently controls the temperature of the upper heat (top heating tubes) and lower heat (bottom heating tubes) to meet the process requirements of different products.

 

- Time setting: Precisely sets the baking time and automatically alarms or stops heating when the time is up.

 

- Rotation speed control: Adjusts the rotation speed of the rotary basket.

 

- Programming memory: High-end models can store baking programs (temperature, time, rotation speed) for multiple products, enabling one-click retrieval and standardized production.

 

Working Process (Closed-Loop Process)

 

● Preheating: Set the upper and lower heat temperatures via the control system, start the heating system, and heat the empty oven to the preset baking temperature.

 

● Loading: Evenly place the baking trays with unbaked blanks into the rotating basket, then close and lock the oven door.

 

Baking and Rotation:

 

● The heating system operates continuously to maintain the internal temperature of the oven.

 

● The rotation system starts, driving all products to rotate at a uniform speed via the rotary basket.

 

● The hot air circulation system works simultaneously to force intense circulation of hot air inside the oven.

 

● Heat Transfer: Under the combined action of rotation and hot air circulation, heat is transferred to the food simultaneously and uniformly through three methods: radiation (from heating tubes), convection (from hot air), and conduction (from baking trays), allowing the food to mature, set, develop color, and release aroma.

 

● Completion and Unloading: When the preset baking time is reached, the control system issues a prompt. The operator stops rotation and heating, opens the oven door, and removes the golden, attractive finished products with uniform color.