Rated vs actual capacity of an IQF freezer

Two quotes that both say "1,000 kg/h" are not necessarily for the same machine. IQF freezer capacity is always tied to a specific product, size and temperature. This article explains the difference between rated and actual capacity, what changes capacity, and what to ask when comparing quotes.

Short answer

Rated capacity is the figure the manufacturer commits to for a reference product, for example HLSO shrimp 16–20 pcs/lb with core temperature in/out +10 °C / –20 °C. Actual capacity is what the line achieves with your product and conditions. Two figures are only comparable for the same product, size, infeed and outlet temperature.

1. Which product is the rated capacity based on?

Every GLORY line states its reference product under the specification table:

• M-series mesh belt and MC-series compact: HLSO shrimp 16–20 pcs/lb, +10 °C / –20 °C.
• S-series steel belt: fish fillet 170–220 g, +10 °C / –20 °C.
• H-series multi-belt: vacuum-packed salmon loin 1,000 g, +10 °C / –20 °C.
• F-series fluidized bed: green peas, +5 °C / –20 °C.

So an M900 (900 kg/h of shrimp) and an S1000 (1,000 kg/h of fish fillet) cannot be compared on kg/h alone.

2. What changes actual capacity

• Product size and thickness: larger shrimp and thicker fillets need longer freezing time.
• Infeed temperature: warmer product means more heat to remove.
• Required outlet core temperature: –18 °C and –20 °C give different results.
• Available refrigeration: each model needs a set refrigeration capacity at about –45 °C evaporating temperature, for example about 170 kW for the M900. Without it, the freezer cannot reach capacity.
• Infeed: if the belt is not fed evenly, capacity drops even when the freezer is able.
• Glazing: glazing rate and number of passes determine the glazer, hardening conveyor and re-freezer configuration behind the freezer.

3. How far above the commitment do GLORY lines run?

With enough refrigeration and infeed, GLORY lines typically run 15–20% above the contracted capacity. For boxed whole shrimp on the heavy-duty mesh belt version, actual capacity for many products runs 20–30% above the rated figure. That margin is your reserve for peak season.

4. What to ask when comparing quotes

• Which product, size, infeed and outlet temperature is the committed capacity based on?
• How many kW of refrigeration are needed, at which evaporating temperature?
• What is the adjustable freezing time range?
• How long does it run between defrosts?
• Does the quote include the infeed conveyor, glazer, hardening conveyor, re-freezer and control panel?

Frequently asked questions

What capacity does my plant need?
Divide daily output by actual production hours and add a margin for peak season. For example, 20 tonnes in 20 hours is 1,000 kg/h. Try the IQF capacity calculator.

Does capacity change when running several products?
Yes. The Master AutoCell® control panel stores up to 512 programs by product, size and target temperature, so each product runs at the right speed.

How do I get an exact figure for my plant?
Fill in the freezer questionnaire. GLORY engineers calculate capacity from your product, size, output and actual refrigeration system.