What Is a Refrigerated Truck?
A refrigerated truck, also known as a refrigerated van, is a type of truck equipped with a refrigeration unit in its cargo compartment, allowing continuous cooling temperature.
Refrigerated vans with similar functionalities have insulated cargo compartments that can temporarily maintain a specific temperature. The development of refrigerated trucks in Japan began in 1958, driven by the demand for food transportation, including milk and ice cream, from U.S. military bases.
The technology of refrigerated trucks has evolved, and modern versions feature computer-controlled refrigeration units, enabling more precise temperature management. Additionally, refrigerated trucks with fuel-efficient hybrid systems have been developed, contributing to environmentally conscious transportation.
Uses of Refrigerated Trucks
Refrigerated trucks are divided into medium-temperature and low-temperature categories based on the storage temperature. They are used for transporting food and other items to supermarkets, convenience stores, restaurants, and more. Medium-temperature refrigerated trucks maintain temperatures around -5°C, suitable for transporting fresh food, while low-temperature refrigerated trucks, capable of storing items at -15°C or below, are ideal for transporting ice cream and frozen food.
Refrigerated trucks are also utilized for transporting biological tissues, blood products, and play a crucial role in various industries. On the other hand, trucks with insulated cargo compartments, known as chilled trucks, are used for transporting items like fresh food, school meals, and bento with less stringent temperature control requirements and shorter delivery times.
Structure of Refrigerated Trucks
The cooling system in a typical refrigerated truck has a basic structure similar to a car’s air conditioner and consists of five main components:
1. Compressor
Utilizes the engine’s power to compress the refrigerant into a gas, then sends it to the condenser.
2. Condenser
Liquefies the high-temperature, high-pressure gas sent from the compressor by cooling it with outside air, then sends it to the expansion valve.
3. Expansion Valve
Reduces the pressure of the high-pressure liquid refrigerant received from the condenser, turning it into a mist and sending it to the evaporator.
4. Evaporator
Vaporizes the mist-like refrigerant liquid received from the expansion valve, absorbing surrounding heat, and circulates it forcefully with a fan.
5. Control Panel
An apparatus for adjusting the temperature inside the refrigerated compartment. It allows temperature management of the refrigerated compartment from the driver’s seat. Additionally, refrigerated trucks use insulation materials such as polyurethane foam or polystyrene foam on the walls, ceiling, and floor to maintain a constant temperature inside and minimize cold air leakage.
Types of Refrigerated Trucks
Refrigerated trucks are categorized into three types based on the cooling method: mechanical, liquid nitrogen, and cold storage.
1. Mechanical Type
Uses the engine’s power similar to an air conditioner, allowing precise temperature control. Most refrigerated trucks adopt this method.
2. Liquid Nitrogen Type
Uses liquid nitrogen, a commonly used cooling agent, to achieve temperatures as low as minus 40 degrees Celsius. Suitable for rapidly cooling items that require it.
3. Cold Storage Type
Utilizes electricity to cool the refrigeration unit’s cooling plate. When not in use for transportation, the refrigeration plate in the cargo compartment is frozen, and during transportation, the frozen plate provides the necessary cooling. This type is more energy-efficient and environmentally friendly.
How to Choose a Refrigerated Truck
1. Payload Capacity
Choosing a refrigerated truck with an appropriate payload capacity is crucial. Insufficient payload capacity can lead to increased transportation frequency, higher fuel and labor costs, and decreased operational efficiency. On the other hand, significantly lower payload capacity than the standard may result in unnecessary expenses such as higher fuel costs. When purchasing a refrigerated truck, it is essential to select one that aligns with the daily payload capacity requirements.
2. Cooling System Method
For mechanical-type refrigerated trucks, choosing between engine-direct and sub-engine systems is a key decision point. The engine-direct system, being lighter, offers fuel savings but cannot cool when the engine is off. The sub-engine system, with a dedicated engine for the refrigeration unit, provides high cooling capacity even when the main engine is off. However, it is heavier and less fuel-efficient.
When selecting a refrigerated truck, careful consideration of the intended use and whether a sub-engine is necessary is crucial.
3. Travel Distance and Internal Temperature
The appropriate type of refrigerated truck depends on the transportation distance and the type of cargo. If the cargo does not require an extremely low temperature, there is no need for a truck that can switch between freezing and refrigeration. For longer distances, it’s essential to consider energy-efficient models, such as those with sub-engines that allow cooling during breaks.
When purchasing a refrigerated truck, it is vital to factor in the transportation distance and internal temperature requirements to make the right choice.