The reefer ISO tank integrates a refrigeration unit (Klinge, Carrier, Daikin, or Star Cool) on the front wall, drawing 380 V 50 Hz or 460 V 60 Hz 3-phase shore power, generator set, or vessel reefer plug. The unit maintains cargo temperature anywhere in the minus 40 to plus 30 deg C envelope, holding the spec across multi-week ocean transits. Pharma reefer tanks (Klinge NMR-262 PHARMA and PFP-572 PHARMA) hold plus 2 to plus 8 deg C with redundant primary and back-up units for critical-temperature pharma cargo.
What reefer is built for
The cargo population is wide because the reefer envelope covers everything from frozen orange-juice concentrate (minus 10 deg C) through dairy and biologics (plus 2 to plus 8 deg C) to premium wines and latex emulsion (cool ambient, 8 to 15 deg C). Latex specifically must stay above 5 deg C to prevent coagulation, and below 30 deg C to prevent ammonia loss; the reefer envelope keeps it in spec on long ocean voyages from South-East Asia to North America and Europe. Fruit-juice concentrates ship at minus 10 deg C to prevent fermentation. Dairy in bulk ships at plus 4 deg C. Pharma actives and biologics ship at plus 2 to plus 8 deg C with redundant cooling.
Construction and materials
316L stainless cylinder with the standard T11 plate stack (6 bar test, MAWP 4 bar, bottom outlet, normal PRV). The defining feature is the refrigeration unit bolted to the front wall, taking up around 0.8 m of frame length and reducing internal cargo volume to about 22,000 L. The unit weighs 1,500 to 2,500 kg, raising tare to 5,500 to 6,500 kg and cutting payload by about 1.5 tonnes versus a non-reefer T11. Insulation 100 mm polyurethane foam minimum, often more on pharma builds.
The Klinge NMR-262 PHARMA and PFP-572 PHARMA are dual-redundant units with primary and back-up refrigeration loops; if one fails the other holds the spec, and the operator’s monitoring system alerts before the cargo goes out of envelope. Telematics standard on all modern reefer tanks: GPS tracking plus temperature logging through the entire transit, downloadable on arrival.
When reefer is the right choice
Reefer is the right tank for any cargo with a tight temperature spec across a multi-week ocean transit. Latex from Indonesia or Malaysia to the US or Europe (8 to 15 deg C). Frozen juice concentrate from Brazil to Europe and Asia (minus 10 deg C). Dairy from New Zealand or Ireland to Asia (plus 4 deg C). Pharma actives globally (plus 2 to plus 8 deg C). Premium wines from Australia, New Zealand, or South Africa to high-temperature destination markets (cool transit at 12 to 16 deg C protects the wine quality).
When reefer is the wrong choice
Reefer is the wrong tank for cargoes that don’t need a tight temperature envelope. The integrated refrigeration unit adds substantial tare and lease cost (USD 30 to 80 per day vs USD 4 to 8 for a non-reefer T11). For cargoes that need only ambient shipping in an insulated tank, an insulated non-refrigerated T11 is the right answer.
How a reefer booking is verified
Pre-loading inspection covers the standard plate stack plus the refrigeration-unit functional test (verify the unit cools to setpoint and holds), the temperature-logger calibration record, and the operator’s history showing successful reefer service for the cargo. Pharma builds require additional verification: redundant-unit operability, alarm-system test, dedicated-fleet history confirming no chemical-cargo cross-contamination, GMP-aligned cleaning protocol.