Humans have refrigerated food for centuries. Ancient civilizations such as the Chinese, Hebrews, Greeks, and Romans placed large amounts of snow into caves and storage pits to keep food longer. In the 1800’s, frozen ice blocks were carried around in the back of wagons and sold to people and businesses to preserve food. The first successful mechanically refrigerated trucks were introduced by the ice cream industry in about 1925.
It wasn’t until 1949 that Frederick McKinley Jones invented an automatic roof-mounted refrigeration system for long haul trucks and railroad cars, to make sure food stayed fresh. Jones was inspired to invent the system after talking with a truck driver who lost his whole cargo of chicken because he couldn’t reach his destination before the ice melted.
Refrigerated Van and Trucks were originally designed to carry perishable freight and are the reason we enjoy fresh food every day, but did you know these vehicles are also used to carry arctic animals safely from their homes to zoo’s, protect paintings and art from significant damage by ensuring low temperature and humidity; nurseries and florists to ensure cut flowers would last longer; bakeries, medical supplies and a morbid application to preserve human bodies in the morgue.
Read more on The History and Impact of Refrigeration and The-hazards-of-food-safety-temperatures.html
What’s Refrigeration? It’s a process of moving heat from one location to another in controlled conditions. The work of heat transport is traditionally driven by mechanical work, but can also be driven by heat, electricity and by other means. Refrigeration is a Closed System that requires keeping an item below room temperature by storing the item in a system or substance designed to cool or freeze. The most common form of refrigeration is provided by systems (i.e. refrigerators) that use a refrigerant chemical to remove heat from items stored inside the system.
What is a Refrigerated Truck? Reefer Trucks as they are known, are Van and Trucks that include a refrigeration unit on the cargo area to maintain specific climates for temperature-sensitive loads.
Main Components of a Refrigeration System?
Compressor – is mounted to the vehicle engine with a compressor mounting bracket and is driven by the vehicles belt drive system. Refrigerant enters the compressor as a low temperature, low pressure gas. The compressor compresses the refrigerant and changes it to a high temperature, high pressure gas.
Condenser – Rooftop or Nose Mounted it receives the high temperature, high pressure refrigerant from the compressor and through the process of heat exchange, assisted by the condenser fan motor, changes the state of the refrigerant to a high temperature liquid. This change of state takes place when the air circulating around the tubing and fins of the condenser coil, cools the refrigerant.
Evaporator – is located in the cargo area of the vehicle. The liquid refrigerant entering the evaporator via the expansion valve is thermostatically controlled to change state from a liquid to a low pressure, low temperature gas. The refrigerant now absorbs the heat from the cargo area by passing air over the evaporator coil assisted by the evaporator fan motor. At this point the refrigerant is refereed to as a “saturated mixture” in the evaporator coil. When this process is complete, the gas returns to the compressor as a low temperature, low pressure gas and this entire process is repeated until the desired temperature is reached.
From Wikipedia – Refrigeration has had a large impact on industry, lifestyle, agriculture and settlement patterns. The idea of preserving food dates back to the ancient Roman and Chinese empires. However, refrigeration technology has rapidly evolved in the last century, from ice harvesting to temperature-controlled rail cars. The introduction of refrigerated rail cars contributed to the westward expansion of the United States, allowing settlement in areas that were not on main transport channels such as rivers, harbors, or valley trails. In most developed countries, cities are heavily dependent upon refrigeration in supermarkets, in order to obtain their food for daily consumption.