The cooling elements used in cold transport look alike from outside: a sealed shell, a filling inside, taken from the freezer and placed beside the load. What sets them apart is the temperature at which the filling melts. What each term covers is explained in the definition article.
Temperature first, then duration. The first step is the range the product has to stay in. A product needing 0-4 °C that touches a plate melting at -18 °C freezes at the surface. Frozen goods travelling with a gel pack that melts near 0 °C slowly thaw.
| Type | Working temperature | The job it suits | Watch out for |
|---|---|---|---|
| Gel pack | Standard types around 0 °C | Short distance, 2-8 °C, flexible placement | Punctures easily; must not touch product that must not freeze |
| Rigid-shell pack | Depends on the filling, read from the label | Daily distribution, frequent washing, stacking | Different fillings are not mixed on one rack |
| Eutectic plate | GEBHARDT: -3, -14, -18, -21 °C | Steady temperature, long rounds, returnable use | Frozen solid at 5 °C below the melting point |
| Dry ice | -78.5 °C | Very low temperature, one-way | Ventilation, gloves, dangerous-goods rules in air cargo |
Eutectic plates and dry ice. The filling of a eutectic plate melts at a set temperature and holds that temperature while it melts. GEBHARDT plates are 34 mm thick and come in standard sizes of 480×280 and 615×378 mm; other melting points are made on request. Dry ice sublimes away and leaves no liquid, but it is bought again for every run and needs ventilation because carbon dioxide builds up in enclosed spaces. GEBHARDT's technical document puts the savings potential of eutectic plates at up to 41% compared with dry ice.
How many. Quantity comes after type and depends on the volume of the container, the outside temperature and the duration. Starting with one plate and finding out on the road that it was not enough is costly; carrying a spare on the first run and measuring with a logger costs less. Send us the route, product and target temperature and we obtain GEBHARDT's thermal calculation and pass it on to you.
Choosing it together with the container
No cooling element lasts as long as expected in an uninsulated box. Plate and container are chosen together: inside an insulated container the plate buys hours, in a cardboard box the same plate buys minutes.
