
Aquatic Products
Handles fish, fillets, shrimp and shellfish with gentle conveying and uniform freezing.
Square’s self-stacking spiral freezer is a compact and hygienic freezer design. Compared to the traditional low-tension spiral freezer, the self-stacking spiral freezer eliminates the rails supporting the belt, which means up to 50% more freezing output with the same footprint.
The conveyors are almost 100% accessible for cleaning thanks to the elimination of the belt rail and drum. The freezer has combined the state-of-the-art clean-in-place (CIP (Cleaning-in-Place)) system.
This open and accessible structure improves hygiene, minimizes downtime for maintenance, and prolongs equipment lifespan by preventing waste accumulation.
Customized to client specifications
Capacity ranges from 300kg to 5000kg/hr
Efficient, Energy-Saving, Easy Cleaning

Product Features
Explore the key product features, including Self-Stacking Belt, Self-contained Freezing Zone, Efficient Evaporator, and the engineering advantages behind this system.

Our self-stacking spiral freezer features a self-stacking belt, chain-driven system, and vertical airflow.
Food can be frozen in less time while maintaining better quality. The self-stacking spiral freezer meets the highest hygiene and energy-efficiency standards.
The self-stacking belt is driven by a chain system and operates completely on rolling balls. The resistance and noise caused by running the chain are reduced, so smaller motors can drive the system.
The belt is not in tension in the run. The belt is less likely to be stretched and deformed. Self-stacking belt stacks on the top of each other’s side links.
This self-stacking feature eliminates the rails supporting the belt.

The unique belt design contains the product in a self-contained freezing zone, for gentle and uniform handling and superior hygiene.
The vertical airflow of high velocity touches the product through all stacks, providing an even, quick, efficient freezing result.
The special holes on the side links also introduce cold air into the product zone and create turbulence. This provides uniform product temperature across the belt and increases the heat-exchanging efficiency.
The centrifugal fans on the top of the coil suck the cold air from the coil and push the high-velocity air down through all belt tiers.

The design was simulated with European professional heat exchanger software.
All tubes are expanded hydraulically rather than mechanically. More uniform expansion and tighter fit between tube and fins. Improved heat exchanging performance.
Variable fin pitch is used to delay the frost formation on the fin surface. Longer frosting interval.
Easy access and cleaning
Tube material: Stainless steel, Aluminum
Fin material: Aluminum

The ADF system blows pulses of pressurized air of high velocity repeatedly over the evaporator fins to remove the frost while the products continue to run in the freezer.
The heat transfer efficiency is significantly improved. Air Defrosting can extend production runtime by 150 to 200% by eliminating frost buildup on the evaporator.

The design eliminates the belt-supporting rails and cages. It is hygienic and easy to clean.
The self-stacking freezer provides multiple automatic cleaning systems: PZC, PZE, and CIP. PZC cleans the product zone that is in direct contact with the product.
PZE cleans the product zone and coil. CIP (Cleaning-in-Place) is the full mode. It cleans product zones, coils, enclosures, and structures.
The systems have multiple cleaning programs for customers to choose from, including lathering, rinsing, disinfectant spraying, and belt drying.
The self-stacking freezer is ideal for quick freezing of fried food, ready meals, and pastries.

Continuous PIR panel fabrication line from German Hennecke. 50mm to 250mm thick. Limited combustibility.
A fully welded stainless steel enclosure is available as an option.

Modular stainless steel fully welded floor, leakproof. Sloped floor, fast drainage through four drains at the corners. Easy Access.

PLC touch screen, friendly interface, easy operation.
Real-time display of equipment running status,
temperature of each area, and fault alarm.
Preset freezing programs tailored for different products.
Technical Specifications
Self-stacking spiral freezer parameters define compact spiral layout, belt width, tiers, airflow, refrigerant, evaporator, defrost, cleaning, and capacity for high-output freezing in a smaller footprint.
| Configuration | Self-stacking spiral — drumless, belt self-stacks on side rails |
|---|---|
| Tiers | 6 – 30 |
| Belt width | 600 – 1,400 mm |
| Insulated Enclosure | PIR / PU, stainless steel skin both sides, optional fully welded interior |
| Infeed / Outfeed height | Low-level (~900 mm from floor) — direct conveyor integration |
| Refrigerant | NH₃ (Ammonia) / CO₂ / Freon — pump-recirculated or DX |
| Evaporator | Aluminium / Stainless steel tube, aluminium fin, variable fin pitch |
| Defrost | Water / Hot gas / ADF (Air Defrost System) |
| Freezing time | Stepless variable frequency adjustable (typically 10–45 min per product spec) |
| Cleaning | Manual / Belt washer / CIP (Cleaning-in-Place) — programmable |
| Typical lead time | 14–18 weeks (custom-engineered configuration) |
| Design life | 15+ years (structural); 8–10 years (belt, normal operation) |
Design Details
Expand any section below for the engineering approach behind each critical subsystem — with links to detailed Technology pages.
The defining feature of the self-stacking spiral is the elimination of the central drum. In a conventional spiral, the belt wraps around a large rotating drum that occupies ~30% of the enclosure interior volume. By removing the drum and letting the belt stack on itself via side rails:
The self-stacking design is inherently IQF-friendly. Without a drum blocking the center of the enclosure, cold air can be directed across the full belt width from both sides:
The belt carries integrated side rails (wear strips) on both edges. As the belt completes each tier, the side rails of the new tier rest precisely on the side rails of the tier below. The entire stack is supported from the base — no drum, no central structure.
Three defrost methods available, selected per your production schedule and refrigerant:
Siemens PLC standard with HMI touchscreen. Real-time monitoring: zone temperatures, belt speed, fan status, evaporator performance. Recipe storage for 50+ products. Optional VPN remote diagnostics — Square engineers troubleshoot ~70% of issues without on-site visit.

Handles fish, fillets, shrimp and shellfish with gentle conveying and uniform freezing.

Freezes prepared and portioned meals continuously while maintaining product shape and presentation.
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Suitable for raw chicken breasts, wings, thighs and fillets in high-capacity processing lines.
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Processes cooked chicken and formed poultry products with stable airflow and consistent freezing results.
Case Studies
Real production lines with performance data — not renderings, not claims. Each installation documented with commissioning data.
Real production lines with performance data — not renderings, not claims. Each installation documented with commissioning data.
Yes. The Air Defrost (ADF) system continuously removes frost during operation, extending run time by 150–200% compared to conventional evaporators.
The self-stacking spiral freezer can be configured for common industrial refrigeration systems, including NH₃ (ammonia), CO₂, Freon, or project-specific refrigeration packages. The final selection depends on temperature, capacity, safety requirements, and site conditions.
We own CE, EAC, INF, CNAS, ISO, ASME, PED, U2, CSA, CRN certifications and 300+ patents, as well as 350+ engineers. Square vertically integrated production ensures quality control from raw materials.
Square offers customized one-stop cold chain solution that meets your requirements. We provide fully customized models with capacities from 300 to 5,000 kg/h, depending on the product and layout. Tailored options include belt width, number of tiers, enclosure material, and infeed/outfeed configuration.
It offers up to 50% more output in the same footprint, easier cleaning, reduced maintenance, and superior hygiene due to the open structure and no belt-support rails.
Engineering Inquiry
Share your product type, target capacity, line layout, utilities, and site conditions. Our engineers will review your requirements and recommend a suitable Self-Stacking Spiral Freezer configuration.