Twin Spiral Freezing Tunnel
The twin spiral freezing tunnel is a large continuous freezing equipment in the food processing industry, featuring two spiral conveying systems combined with a low-temperature environment, allowing food to quickly pass through the ice crystal formation zone during conveying for efficient freezing.
Working Principle
Step Description
① Material Input Food enters the twin spiral structure through the inlet (usually low-level feeding)
② Spiral Conveying The two wire mesh belts are driven separately, and food moves in reverse spiral motion on the two spirals to prevent accumulation
③ Uniform Cooling Cold air is forced to circulate in the spiral gaps, and food is subjected to both low temperature and high-speed airflow
④ Rapid Discharge Low-temperature discharge outlet (at the same level as the inlet, low-level discharge), continuous operation
The refrigeration system consists of compressor → condenser → expansion valve → evaporator. The strong cold air generated by the evaporator forms an annular air duct through symmetrical baffles, achieving full heat exchange with the food.
Core Parameters
Parameter Value Range
Freezing Temperature -35℃ ~ -45℃ (zone-controlled temperature available)
Freezing Time 5 ~ 30 minutes (depending on product)
Processing Capacity 500 ~ 3000 kg/h
Operating Electricity Cost Approximately 0.1 ~ 0.15 RMB/kg
Temperature Difference in Chamber ≤ ±2℃
Advantages over Single Spiral
Comparison Item Single Spiral Twin Spiral
Inlet/Outlet High inlet low outlet / low inlet high outlet Same level, low inlet low outlet
Floor Space Larger More compact, space-saving
Output 500~1500 kg/h 1000~3000 kg/h
Production Line Integration Limited More flexible, easy automation integration
Applicable Products General products Especially suitable for block foods requiring long freezing time (e.g., large meat cuts, whole fish, pastry, etc.)
In addition, the drive motor operates at ambient temperature outside the chamber, not increasing the heat load inside, and facilitates maintenance without stopping the machine.
Applicable Products
🥟 Pastry: Steamed buns, dumplings, tangyuan, siomai, zongzi
🥩 Meat Products: Beef and mutton cuts, chicken and duck products
🐟 Aquatic Products: Whole fish, shrimp meat, crab sticks
🥬 Fruits/Vegetables / Prepared Foods / Dairy Products / Ice Cream
One-Sentence Summary
Twin spiral freezing tunnel = twin spiral conveying + forced cold air circulation + PLC automatic control, achieving large-capacity, high-quality, low-energy continuous freezing with a compact structure, making it the mainstream choice for production line upgrades in medium and large food enterprises.
