Refrigerated van

A refrigerated van (also called a refrigerated wagon) is a railway goods wagon with cooling equipment. Today they are designated by the International Union of Railways (UIC) as Class I.

The first wagons were cooled with ice that had been cut in winter from special pools or lakes. It was Gustavus Swift who succeed in the winter of 1877 for the first time in developing an efficient cooling system for railway wagons for Chicago businesses and meat producers. It circulated air through the ice and then through the entire wagon in order to cool it down. This system was the basis of the success of the , the Chicago slaughterhouses. The cooled wagons made it possible for the first time to transport the meat of slaughtered animals to the whole of the USA. Later, manufactured ice was used, but this rapidly gave way to other means of cooling; the simplest was the substitution of normal (water) ice by dry ice. With the increasing reliability of combustion engines, engine-powered refrigerator vans emerged. There are even vans whose cooling is achieved by the evaporation of liquid gas.

Compared with machine-cooled vans, ice-cooled wagons have the disadvantage of uneven temperature control, because the cooling effect is only achieved by air circulation. On the other hand, machine-cooled wagons are expensive to maintain and operate, but can be set to the desired temperature and maintained at that temperature throughout the entire journey. They are also better suited to transporting goods at deep-freeze temperatures of around −30 °C (−22 °F), whereas evaporators and ice-cooling are more suited to maintaining temperatures of around 0 °C (32 °F). Banana transport wagons with gas evaporators have an optimum internal temperature of +14.4 °C (57.9 °F) In addition to proper refrigerated vans, there are covered wagons with thermal insulation and, in some cases, even those are equipped with refrigerating sets. These wagons can only operate at temperatures between 0 and +20 °C (32 and 68 °F), where a constant internal temperature is desired.

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