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Revision as of 19:53, 17 August 2013 by imported>Chunbum Park (→‎San Diegan: Refrigerator Car)
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Refrigerator car


(PD) Drawing: UnknownAn early refrigerator car design, circa 1870. Hatches in the roof provided access to the ice tanks at each end of the car.

A refrigerator car (or "reefer") is a refrigerated boxcar, a piece of railroad rolling stock designed to carry perishable freight at specific temperatures. Refrigerator cars differ from simple insulated boxcars and ventilated boxcars (commonly used for transporting fruit), neither of which are fitted with cooling apparatus. Reefers can be ice-cooled, come equipped with any one of a variety of mechanical refrigeration systems, or utilize carbon dioxide (either as dry ice, or in liquid form) as a cooling agent. Milk cars (and other types of "express" reefers) may or may not include a cooling system, but are equipped with high-speed wheelsets and other modifications that allow them to travel with passenger trains. Reefer applications can be divided into four broad groups: 1) dairy and poultry producers require refrigeration and special interior racks; 2) fruit and vegetable reefers tend to see seasonal use, and are generally used for long-distance shipping (for some shipments, only ventilation is necessary to remove the heat in transit created by the ripening process); 3) manufactured foods (such as canned goods and candy) as well as beer and wine do not require refrigeration, but do need the protection of an insulated car; and 4) meat reefers come equipped with specialized beef rails for handling sides of meat, and brine-tank refrigeration to provide lower temperatures (most of these units are either owned or leased by meat packing firms).

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