Choosing a liquid nitrogen cabinet freezer comes down to fixing three numbers first: how many kilograms go in per batch, how many kilograms must come out per hour, and what core temperature the product has to reach. Those three numbers pick the model. Door type, shelf spacing and nitrogen pressure are configuration details decided afterwards.
Bottom line (TL;DR):
- Three numbers pick the model: kilograms loaded per batch, kilograms that must come out per hour, and the target core temperature
- LFC-300 runs around 300 kg/h with a manual cabinet door for lines with limited floor space; LFC-600 runs around 600 kg/h where a full rack trolley rolls in and out
- LFC-1200 loads 0-1200 kg per zone with four independently controlled zones, for running several products at once
- All three cover -150°C to room temperature; the LFC-300 and LFC-600 hold ±1°C with ±3°C uniformity, the LFC-1200 holds ±2°C
- Rated throughput is an order-of-magnitude reference to machine capacity; real capacity has to be measured with your material
Across the three cabinet models we build, the mapping is: around 300 kg/h with single-door manual loading and limited floor space, use the LN2 blast freezer LFC-300; around 600 kg/h where a full rack trolley has to roll in and out, use the LFC-600; and where a single zone loads 0-1200 kg, four zones need independent control and several products run at once, use the LFC-1200. The table below gives the parameters; the sections after it explain the conditions each model suits.
Parameter comparison of the three models
| Item | LFC-300 | LFC-600 | LFC-1200 |
|---|---|---|---|
| Model code | DKN-LFC-300 | DKN-LFC-600 | DKN-LFC-1200 |
| Internal chamber | 900×1320×1800 mm | To be confirmed on order | 2000×1500×1750 mm × four zones |
| External dimensions | 1740×1730×2220 mm | 2900×1700×2450 mm | 8730×2350×2170 mm |
| Working temperature | -150°C to room temperature | -150°C to room temperature | -150°C to room temperature |
| Temperature control accuracy | ±1°C | ±1°C | ±2°C |
| Temperature uniformity | ±3°C | ±3°C | To be confirmed on order |
| Cooling rate (empty) | Not lower than 20°C/min | Not lower than 20°C/min | Not higher than 50°C/min |
| Installed power | 2.5 kW | 5 kW | 12 kW |
| Power supply | 380V/50Hz | 380V/50Hz | 380V wide voltage |
| Nitrogen pressure | 5-8 bar | 5-8 bar | 6-8 bar |
| Throughput | 300 kg/h | 600 kg/h | 0-1200 kg per zone |
| Oxygen monitoring | — | — | 19.5%-21.5% |
| Door and zoning | Cabinet, manual door | Cabinet, manual door | Cabinet, side door, four independent zones |
The LFC-600 internal chamber size and the LFC-1200 temperature uniformity figure are not fixed in our current technical documents; they are confirmed per order rather than estimated here.
Step one: separate batch weight from hourly throughput
These two numbers are often mixed up. Batch weight is the total mass loaded in one cycle; hourly throughput is the mass discharged per hour under a continuous rhythm. If your line runs in batches, what matters is batch weight and cycle time. If the line feeds and discharges continuously, throughput is the figure to use.
The LFC-300 takes 40 trays per rack load, using stainless steel trays of 400×600×25 mm, with a trolley of 1050×750×873 mm. The LFC-1200 is equipped with 10 racks, each 1300×1500×1470 mm with an upper and lower tier, and its four zones can be loaded independently. Dividing batch weight by the load per tray tells you how many trays a cycle needs and whether the rack capacity is enough.
Step two: product form — bulk, tray or bagged
Product form determines the rack configuration and the loading method, and it directly affects freezing time:
- Bulk particulate products (crayfish, small cuts) spread thin on the tray, so cold air passes through quickly
- Tray-loaded products (fish fillets, cuts, peeled shrimp) move in and out as whole trays, needing only airflow gaps between trays
- Bagged or skin-packed products (prepared meal packs, vacuum bags) carry the packaging layer as thermal resistance, so the same weight needs a longer dwell time
The LFC-300 drawing shows a standard shelf pitch of 75 mm, and the pitch can be redesigned for the product. Both the pitch and the tray specification should be confirmed together with the product data before ordering.
Step three: target core temperature changes time, not model
The criterion for blast freezing is: passing through the 0°C to -5°C ice crystal formation band within 30 minutes, reaching a core temperature below -18°C, with ice crystals below 100 μm in diameter. Whether the target is -18°C or lower changes the dwell time in the cabinet and the nitrogen consumed; it does not change which model you need.
All three cabinets share the same temperature capability, -150°C to room temperature. What differs is control accuracy and cooling rate: the LFC-300 and LFC-600 hold ±1°C with ±3°C uniformity and cool at no less than 20°C/min empty; the LFC-1200 holds ±2°C and is rated at no more than 50°C/min empty, giving a wider adjustable range. For products sensitive to temperature swing, the accuracy figures matter more than the range.
Step four: why throughput cannot be read from weight alone
Wherever our documents state 300 kg/h or 600 kg/h, the figure is followed by “varies with product and packaging”. The reason is straightforward: removing the same temperature drop takes different amounts of heat out of different materials.
- Higher moisture content means more water to freeze and more refrigeration per kilogram
- Fat has a clearly different specific heat from water, so high-fat products freeze along a different curve
- Packaging thickness and layer count add thermal resistance, slowing bagged product compared with bulk
- Different inlet temperatures mean a different starting point
The rated throughput is therefore an order-of-magnitude reference to machine capacity rather than a figure for one specific product. Real capacity has to be measured with your material.
Step five: floor space, power and ancillaries
The external dimensions differ substantially: LFC-300 at 1740×1730×2220 mm, LFC-600 at 2900×1700×2450 mm, LFC-1200 at 8730×2350×2170 mm. Check workshop door widths, aisle turning radii and trolley or forklift routes against these figures.
On power, the LFC-300 and LFC-600 run on 380V/50Hz with installed power of 2.5 kW and 5 kW; the LFC-1200 uses 380V wide voltage with 12 kW installed. Cabling from the main supply to the control cabinet is installed by the buyer.
Ventilation ducting, nitrogen and the nitrogen tank are supplied by the buyer. Each LFC-1200 is fitted with an oxygen concentration monitor set to 19.5%-21.5%, interlocked with the machine.
What must be confirmed by trial with the actual product
The following are better measured than calculated, using a machine trial or a small batch:
- Time for the product core to reach the target temperature at the intended batch load
- Actual nitrogen consumption
- Effect of packaging format on freezing time
- Match between shelf pitch, tray size and product dimensions
- Loading and unloading rhythm and the staffing it requires
Where the figures come from
Parameters here are taken from three Kunning documents — the DKN-LFC-300 cabinet technical agreement, the DKN-LFC-600 cabinet technical agreement and the 1200KG cabinet technical proposal — together with the LN2 cabinet product page on this site. Where a document gives no fixed value, the cell is left blank or marked as confirmed on order.
Need a selection recommendation
Tell us your product form, unit pack weight, throughput requirement and target core temperature, and we will work out the configuration and trial plan around your material.
Related companies: Yuanxian Machinery manufactures vacuum pre-cooling and vacuum rapid-cooling equipment for fruit, vegetables and cooked food, and its export site Vacuum-Fresh handles overseas enquiries for that same vacuum cooling line.
Frequently asked questions
What is the hourly throughput of the LFC-300?
The technical documents rate it at 300 kg/h, with the note that the figure varies with product and packaging. That makes 300 kg/h an order-of-magnitude reference to machine capacity rather than a fixed value for one product; real capacity has to be measured with your material.
Which numbers have to be fixed first when choosing an LN2 cabinet freezer?
Three: kilograms loaded per batch, kilograms that must come out per hour, and the target core temperature. Those three pick the model; door type, shelf spacing and nitrogen pressure are configuration details decided afterwards.
How do the LFC-1200, LFC-300 and LFC-600 differ in temperature control and zoning?
The LFC-300 and LFC-600 hold ±1°C with ±3°C temperature uniformity and cool at no less than 20°C/min empty, and have a manual cabinet door. The LFC-1200 holds ±2°C, is rated at no more than 50°C/min empty, and has a side door with four independent zones loading 0-1200 kg each.