Flat plate IQF freezer is a continuous individual quick freezing unit using a flat, seamless stainless steel belt, running in a freezing chamber at -38°C to -42°C and bringing products from +10°C down to -18°C in 5 to 30 minutes. The flat belt surface keeps the product surface clean with no mesh marks — the deciding factor for fish fillets, meat portions and export goods with appearance requirements.
Tan Long designs and manufactures flat plate IQF freezers in three capacity ranges 500, 750 and 1,000 kg/h (designated TSF.500 / TSF.750 / TSF.1000) at our factory in Duc Hoa 1 Industrial Park, Tay Ninh (formerly Long An), for fillet and whole fish, meat, battered products and agricultural produce. The equipment runs on both NH3 refrigerant and Freon.
Which industries use flat plate IQF freezers?
Below are the industry groups in which Tan Long has installed the most flat plate IQF freezers:
- Seafood processing: fish fillets, shrimp, squid and frozen export products.
- Food and meat processing: carcass meat, cut meat and ready-prepared foods.
- Agricultural produce and vegetables: vegetables and fruit that need rapid cooling after harvest.
Each sector has different requirements for temperature range, contact materials and capacity. Please contact Tan Long's engineering team for advice on the right configuration for your products.
What is a flat plate IQF freezer? Operating principle and technical standards
Outstanding technical characteristics of Tan Long freezing conveyor
- Super fast freezing of multiple items on the same conveyor belt.
- High freezing capacity, low weight loss rate after freezing
- Energy savings come from optimised design, maximising freezing capacity per unit of electricity consumed, together with the ability to self-balance the pressure inside and outside the freezing chamber, which minimises cold air loss.
- Continuous operating time, no need to stop production to defrost the belt and evaporator up to 23 hours and when needed can run up to 48 hours without stopping the conveyor belt to defrost the evaporator
- Specialized conveyor belt for freezing made of stainless steel with extremely high heat transfer coefficient, manufactured in EU
- Easy to clean all parts inside and outside the conveyor belt. Drain the floor thoroughly after cleaning.
- Design complies with HACCP/FDA standards for food hygiene and safety, high durability, stable operation, beautiful appearance
- Safe and user-friendly control system designed for food processing environment with high stability and precision, ready to connect to all communication networks in SCADA system
Freezing principle
Products move continuously through the freezing chamber on a flat plate belt made of food-grade stainless steel. Through an air distribution system designed around the COANDA effect, high-velocity cold air jets blow directly and continuously onto the top surface of the product and the underside of the belt. The COANDA effect rapidly forms a thin ice layer around the product surface, which reduces moisture loss and prevents the product from deforming. The COANDA effect together with the high heat transfer coefficient of the belt makes freezing fast and even.
Freezer chamber insulation panel
Wall and ceiling panels are insulated with 125mm thick polyurethane, density 40-42kg/m3, sprayed with high pressure sprayer.
- Wall panel: Inside covered with 0.6mm thick SUS 304 stainless steel, outside covered with 0.8mm thick SUS 304 stainless steel with anti-scratch tape.
- Ceiling panel: Inside covered with 0.6mm thick SUS 304 stainless steel, outside covered with 0.6mm thick SUS 304 stainless steel with anti-scratch tape.
- Base panel: The inside is covered with 1.2mm thick SUS 304 stainless steel, the outside is covered with 0.6mm thick SUS 304 stainless steel, cast and welded seamlessly, waterproof. The IQF base is sloped enough to drain water thoroughly during cleaning.
- Doors for cleaning and performing repair and maintenance work
The door is insulated with 125mm thick polyurethane, density 40-42kg/m3. Both sides of the door are covered with 0.8mm thick SUS 304 stainless steel covered with anti-scratch tape. The door lock and hinges are made of SUS 304 stainless steel or plastic. The door is equipped with silicone gasket, anti-snow heating resistor and lock with anti-lock mechanism.
Conveyor
Using flat conveyor belt specialized for seafood processing industry, made of stainless steel with high thermal conductivity, meeting the most demanding food hygiene and safety standards.
Condenser
The evaporator uses stainless steel or copper heat exchange tubes and aluminum fins depending on the refrigeration system. The technical parameters of the evaporator are calculated and selected in the most optimal way to ensure high heat exchange efficiency, continuous operation for a long time, saving energy costs. The evaporator is provided by famous suppliers such as Guntner, Thermofin, Kelvion (EU).
Evaporator fan
Fans are made of aluminum alloy, high performance, low energy consumption, supplied by Ziehl-Abegg or Rosenberg of Germany.
The fan motors are specially designed for IQF, with IP56 standards for complete insulation and moisture resistance. The motor housing is covered with a special protective layer that helps them operate durably in low temperature environments. The motors are supplied by ABB or WEG.
Control cabinet
The control cabinet is made of rust-proof stainless steel, has moisture-proof and waterproof functions. Equipment and components come from famous brands from the EU, USA or Japan such as Rockwell, Schneider, Siemens ABB and Mitsubishi.
Flat plate IQF freezer specifications (TSF) | ||||
PARAMETER | UNIT | TSF.500 | TSF.750 | TSF.1000 |
| Freezing capacity | kg/h | 500 | 750 | 1000 |
| Product Type | Fish fillets/whole, breaded meat/fish, agricultural/seafood products… | |||
| Product inlet/outlet temperature | ⁰C | +10 / -18 | ||
| Freezer temperature | ⁰C | (-38 ÷ -42) | ||
| Freezing time | minute | (5 ÷ 30) | ||
| Cooling capacity | kW | 120 | 180 | 240 |
| Refrigerant | NH3, Freon | |||
| Translation method | Fluid pump / LVS (Low Volume System) | |||
| Snow removal method | By hot water / gas | |||
| Conveyor type | Flat stainless steel sheet for food use | |||
| Conveyor width | mm | 1500 | 1500 | 1500 |
| Panel shell size | mm | 10700L*3300W*2900H | 15450L*3300W*2900H | 20200L*3300W*2900H |
| Insulated panel | 125mm thick PU covered with 304 stainless steel, density 40-42 kg/m | |||
| Power supply | AC 380V / 3-phase / 50Hz | |||
Why choose a Tan Long flat plate IQF freezer
The four points below are all verifiable, not self-assessment:
| Criteria | Details |
|---|---|
| Manufactured in Vietnam | The chamber housing, frame and system are manufactured at the Tan Long factory in Duc Hoa 1 Industrial Park, Tay Ninh (formerly Long An). Machine dimensions can therefore be adapted to the plant layout instead of having to take a ready-made imported configuration. |
| Genuine branded components | Güntner, Thermofin or Kelvion evaporators · Ziehl-Abegg or Rosenberg fans (Germany) · ABB or WEG motors · Rockwell, Schneider, Siemens, ABB, Mitsubishi electrical equipment · stainless steel belts imported from the EU. |
| Proven in service | 29 projects since 2005. The plant at Kyokuyo Vina Foods alone received 08 high-speed IQF freezers (05 units at 500 kg/h and 03 units at 600 kg/h, 4,300 kg/h in total). |
| One party accountable | Design, manufacturing, installation, commissioning and maintenance by the same contractor — if the equipment fails to reach its design temperature, there is no need to arbitrate responsibility between several parties. |
In-house manufacturing also pays off later: when an assembly needs replacing after years of operation, Tan Long can rebuild it to the exact original installation dimensions, so the plant does not have to modify the location or wait for imports.
Scope of work Tan Long takes on
- Survey of the floor space, output per shift and main product types.
- Calculation of the cooling load, selection of the machine configuration and the refrigerant (NH3 or Freon).
- Manufacturing at the factory, with inspection before despatch.
- Installation on site, electrical and piping connections.
- Commissioning until the design temperature and output are achieved.
- Handover of as-built drawings, commissioning records and operating instructions.
- Regular maintenance under the contract.
Standard configurations of this line: TSF.500 / TSF.750 / TSF.1000 — 500, 750 and 1,000 kg/h. Beyond these three levels, Tan Long also designs to the output of each individual plant — send us your output per shift and product types to receive a load calculation sheet and a quotation.
Comparing mesh belt IQF, flat plate IQF and REF re-freezing belts
The three belt freezer lines Tan Long builds solve three different problems on the same processing line. The table below compares them on the actual parameters of each line:
| Criteria | Mesh belt IQF (TMF) | Flat plate IQF (TSF) | REF re-freezing (TMRF) |
|---|---|---|---|
| Capacity | 500 / 750 / 1.000 kg/h | 500 / 750 / 1.000 kg/h | 600 / 900 / 1.200 kg/h |
| Suitable product | PTO, HLSO, HOSO, PD and Nobashi shrimp, battered products | Fish fillets and whole fish, meat, battered products, agricultural produce | Already frozen goods that need surface re-freezing after glazing |
| Time in the chamber | 3 – 55 minutes | 5 – 30 minutes | 2 – 15 minutes |
| Cooling capacity | 120 / 180 / 240 kW | 120 / 180 / 240 kW | 30 / 45 / 60 kW |
| Conveyor type | Food-grade stainless steel mesh | Food-grade stainless steel flat plate | Food-grade stainless steel mesh |
| Conveyor width | 1.800 mm | 1.500 mm | 1.800 mm |
| Shell dimensions (smallest version) | 7.200 × 3.600 × 2.900 mm | 10.700 × 3.300 × 2.900 mm | 3.700 × 3.500 × 2.900 mm |
| Room temperature | -38 to -42 °C | -38 to -42 °C | -38 to -42 °C |
| Product inlet/outlet temperature | +10 / -18 °C | +10 / -18 °C | +10 / -18 °C |
| Refrigerant | NH3 or Freon | NH3 or Freon | NH3 or Freon |
The most notable point in the table: the re-freezing belt needs only 30 – 60 kW of refrigeration capacity and takes up less than half the floor area of an IQF belt freezer, because it only re-freezes the surface layer after glazing rather than cooling the whole product mass. This is why the two machines complement each other on the same line instead of replacing each other.
Which belt freezer to choose for your plant
- Loose products, small in size, needing even cold air flow all around the product — shrimp, small seafood, battered items: choose mesh belt IQF freezer. The mesh surface lets cold air reach the underside of the product as well.
- Portioned products that must keep a clean flat surface with no mesh marks — fish fillets, meat portions: choose the flat plate IQF freezer. In return, at the same capacity the machine is about 40 – 50% longer.
- Already frozen goods that have passed through glazing and need the ice glaze re-frozen: choose the REF re-freezing belt, usually installed immediately after glazing machines on the same line.
When the choice of line is not yet clear, the right approach is to calculate the output per shift and the main product types first, and only then settle on the equipment. Tan Long provides design consulting and cooling load calculation before quoting.
Compared with other freezing equipment
The flat plate IQF freezer is for products that need a flat contact surface. The remaining groups suit other product forms:
- Mesh belt IQF freezer — the mesh surface lets air reach the underside as well, suiting small loose items such as shrimp and cut fillets.
- Refreezing conveyor — used after battering or glazing to bring products back into the storage temperature range.
- Contact freezer — batch freezing for block products, a lower investment when the line is not yet running continuously.
See the full range of industrial refrigeration equipment built by Tan Long.
Frequently asked questions about flat plate IQF freezers
When should a flat plate belt be chosen instead of a mesh belt?
Choose the flat plate when the product is portioned and surface appearance is an acceptance criterion — fish fillets, meat portions, battered items that stick easily. A mesh belt leaves marks on soft product surfaces; a flat plate does not. For small loose items such as shrimp, the mesh belt IQF freezer is more effective because the cold air can also reach the underside.
How much floor space does a flat plate IQF freezer need?
Panel shell dimensions by capacity: TSF.500 is 10,700 × 3,300 × 2,900 mm, TSF.750 is 15,450 × 3,300 × 2,900 mm and TSF.1000 is 20,200 × 3,300 × 2,900 mm. At the same capacity the flat plate version is about 40 to 50% longer than the mesh version — a point that must be factored into the layout from the plant design stage.
How long does freezing take on a flat plate belt?
From 5 to 30 minutes depending on the thickness and type of product, with a chamber temperature of -38°C to -42°C, product in at +10°C and out at -18°C. The thicker the product, the longer it stays in the chamber, and the longer the belt required.
What is the belt made of, and does it meet food hygiene standards?
A flat plate stainless steel belt dedicated to food use, with high thermal conductivity, meeting food safety and hygiene standards. The chamber housing uses 125 mm PU panel at a density of 40–42 kg/m³, clad on both faces with SUS 304 stainless steel; the doors have silicone sealing gaskets, anti-frost heating elements and an anti-entrapment mechanism.
What refrigerant does the belt freezer use, and how does it defrost?
It runs on both NH3 and Freon, with liquid feed by liquid pump or LVS (Low Volume System), and defrosting by water or hot gas. The choice of refrigerant should be settled when the overall refrigeration system of the plant is designed, rather than decided separately for each unit.
Does Tan Long manufacture in house or import?
Tan Long designs and manufactures the chamber housing, frame and system at its factory in Duc Hoa 1 Industrial Park, Tay Ninh (formerly Long An), so dimensions can be adapted to the floor space. Assemblies requiring high precision are imported: Güntner / Thermofin / Kelvion evaporators, Ziehl-Abegg or Rosenberg fans (Germany), ABB or WEG motors, and Rockwell, Schneider, Siemens, ABB, Mitsubishi electrical equipment.
Request consulting and a belt freezer quotation
Tan Long designs and manufactures freezing belt systems at its factory in Duc Hoa 1 Industrial Park, Tay Ninh (formerly Long An), so capacity and dimensions can be adapted to the actual layout of each plant. Call 0933 357 058 (Mr. Thinh) or send a quotation request with your output per shift and your main product type.
Technical standards applied to flat plate IQF freezers
Equipment supplied by Tan Long is manufactured to the following standards and material requirements:
- HACCP
- FDA
- SUS 304 stainless steel
- polyurethane insulation
- NH3 refrigerant
- Freon refrigerant
- IP protection rating
Depending on each project's requirements, the engineering team will advise on the material configuration and connection standards that best suit the plant's existing system.
The flat plate IQF freezer consulting and supply process at Tan Long
Tan Long controls both design and manufacture at its plant in Duc Hoa 1 Industrial Park, Tay Ninh (formerly Long An), so the investor deals with a single point of contact from survey to handover:
- Survey and requirement definition: engineers work directly at the plant to establish capacity, layout, refrigerant and real operating conditions.
- Technical proposal: calculating a suitable configuration and discussing it with the investor's technical team before it is fixed.
- Detailed design: drawings are prepared and materials and equipment selected to match the refrigerant and the operating temperature range.
- Manufacture and works testing: machining, assembly and a test run before the unit leaves the factory.
- Installation and acceptance: connection into the plant's system, load testing and handover with the technical documentation.
- Warranty and operating support: operating instructions for the plant's technical team and fault support during the warranty period.
Related technical reading
- How to operate an air blast freezer correctly | Tan Long
- Key characteristics of the different IQF belt freezers | Tan Long
- Structure and working principle of contact freezer
- What is IQF freezing conveyor? Structure and operating principle
- How Impingement freezing works | Tan Long
Related pages
- Mesh belt IQF freezer – specifications and applications
- REF re-freezing belt – specifications and applications
- Industrial cold storage – turnkey design and installation
- NH3 refrigeration systems for processing plants
- Kyokuyo Vina Foods project – 08 high-speed IQF freezers
- 29 projects delivered by Tan Long
- The range of industrial refrigeration equipment Tan Long designs and builds
- Design consultancy, installation and maintenance services for refrigeration systems
