Refrigerator car
Reefers can be ice-cooled, come equipped with any one of a variety of mechanical refrigeration systems, or use carbon dioxide (as dry ice) or liquid nitrogen 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 trucks and other modifications that allow them to travel with passenger trains.
After the end of the American Civil War, Chicago, Illinois emerged as a major railway center for the distribution of livestock raised on the Great Plains to Eastern markets.
Upon arrival at the local processing facility, livestock were slaughtered by wholesalers and delivered fresh to nearby butcher shops for retail sale, smoked, or packed for shipment in barrels of salt.
As early as 1842, the Western Railroad of Massachusetts was reported in the June 15 edition of the Boston Traveler to be experimenting with innovative freight car designs capable of carrying all types of perishable goods without spoilage.
That same year, the Ogdensburg and Lake Champlain Railroad (O&LC) began shipping butter to Boston in purpose-built freight cars, using ice for cooling.
During the same period Gustavus Swift experimented by moving cut meat using a string of ten boxcars with their doors removed, and made a few test shipments to New York during the winter months over the Grand Trunk Railway (GTR).
Detroit's William Davis patented a refrigerator car that employed metal racks to suspend the carcasses above a frozen mixture of ice and salt.
In 1868, he sold the design to George H. Hammond, a Detroit meat packer, who built a set of cars to transport his products to Boston using ice from the Great Lakes for cooling.
Swift's attempts to sell Chase's design to major railroads were rebuffed, as the companies feared that they would jeopardize their considerable investments in stock cars, animal pens, and feedlots if refrigerated meat transport gained wide acceptance.
In response, Swift financed the initial production run on his own, then — when the American roads refused his business — he contracted with the GTR (a railroad that derived little income from transporting live cattle) to haul the cars into Michigan and then eastward through Canada.
On the east coast of the United States, in 1920 the company Fruit Growers Express (FGE) was established and owned by a consortium of eastern railroads to serve the wholesale market for refrigerated produce delivered by railcar.
It was found, however, that top-icing only benefited the uppermost layers of the cargo, and that the water from the melting ice often passed through spaces between the cartons and pallets with little or no cooling effect.
The United States Office of Defense Transportation implemented mandatory pooling of class RS produce refrigerator cars from 1941 through 1948.
The Topeka, Kansas shops of the Santa Fe Railway built five experimental refrigerator cars employing liquid nitrogen as the cooling agent in 1965.
The move was in response to rising fuel costs, and was an attempt to eliminate the standard mechanical refrigeration systems that required periodic maintenance.
Several hundred "cryogenic" refrigerator cars were placed in service transporting frozen foodstuffs, though they failed to gain wide acceptance (due, in part, to the rising cost of liquid carbon dioxide).
The 55-foot (16.76 m)-long cars were blanketed with a layer of insulation, equipped with roof hatches for loading, and had centerflow openings along the bottom for fast discharge.
A mechanical refrigeration unit was installed at each end of the car, where sheet metal ducting forced cool air into the cargo compartments.
[12] The cars' irregular, orange-colored outer surface (though darker than the standard AT&SF yellow-orange used on reefers) tended to collect dirt easily, and proved difficult to clean.
For fruits and vegetables, ventilator cars were sufficient due to the relatively short distances involved, whereas since meat require low temperature storage, they were therefore typically transported by ship, since most major Japanese cities are located along the coast.
In 1966, JNR developed the ReSa 10000 and ReMuFu 10000 type [ja] refrigerated cars that could travel at 100 km/h (62 mph) They were used in fish freight express trains.
Due to the shorter distance to be travelled in the United Kingdom, the need for refrigeration was limited to specialised goods, which could in express-train format - mostly run overnight to avoid delays from passenger traffic - be transported in suitable timescales of less than a day from the area of production to processing, or onwards to the point of consumer consumption.
DB Cargo UK runs Europe's longest-distance single-operator handled train from Valencia, Spain to Barking in East London twice weekly, in partnership with Eddie Stobart Logistics and retailer Tesco's, shipping fresh fruit and produce 1,800 km (1,118 mi) in refrigerated ISO containers.
"Express" reefers are typically employed in the transport of special perishables: commodities with a refrigerated shelf life of less than seven days, such as human blood, fish, green onions, milk, strawberries, and certain pharmaceuticals.
The earliest express-service refrigerator cars entered service around 1890, shortly after the first express train routes were established in North America.
Most units designed for express service are larger than their standard counterparts, and are typically constructed more along the lines of baggage cars than freight equipment.
In 1948, the REA roster (which would continue to expand into the 1950s) numbered approximately 1,800 cars, many of which were World War II "troop sleepers" modified for express refrigerated transport.
Once the "Agricultural Exemption Clause" was removed from the Interstate Commerce Act, railroads began aggressively pursuing trailer-on-flatcar (TOFC) business (a form of intermodal freight transport) for refrigerated trailers.
Taking this one step further, a number of carriers (including the PFE and SFRD) purchased their own refrigerated trailers to compete with interstate trucks.
