Reefer Containers,How It Works? and Temperature

What is a reefer container? Should it be your next big investment? Here we talk about reefer, terms and where to get the best price.

what is Reefer Container ?

Refrigerated containers are simply large refrigerators carried by container ships to move temperature-sensitive goods. It can be like ice cream, meat, or vegetables. Refrigerated containers are literally cool because they keep the cargo at the required temperature. It is usually between -30 ° C and + 30 ° C.

Reefer is a nickname derived from the reefer container, which is the real name of the box. Like many other types of containers, refrigerated containers come in different sizes and different technologies. However, as a rule of thumb, you will most likely come across a 20-foot reefer, also known as TEU.

Demand for refrigerated containers has grown significantly in the last few years. And that success story isn’t over yet. You probably know by looking at reading about them here.

How does a reefer container work?

Let’s start with the basics of how reefer actually works.

As you can see in the photo on the left, the floor of the reefer container looks different. Flooring grooves are also known as T-deck. These T-shaped dents are important because it is the way the container distributes cold air from the bottom. In other words, the reefer moves cold air from the floor around the container.

The T-shape allows for a consistent supply of air throughout the shipment. Guarantees a perfect air exchange with the product.

The generator (or generator) is usually mounted in a reefer to provide cooling / electricity to the container. These generators need to work both abroad and on the go by truck. Therefore, it is usually a combination of a fuel generator and an electric generator. And it gives you an advantage:

The refrigeration unit can maintain or reduce the temperature of the cargo even in the most difficult situations. The important point here is that the refrigeration unit is not designed to cool the goods. During shipping, it only maintains the temperature of the pre-cooled cargo.

However, reefer is not only good at keeping cold, but also good at keeping temperatures up to 30 ° C if needed.

Reefer and refrigerated cargo reefer temperature control **

Refrigerator temperature control
Refrigerated containers can be your best friend when shipping goods that need to maintain a certain temperature. However, internal air circulation is essential for refrigerated containers to maintain a constant temperature. The way these boxes ensure this is to constantly circulate the controlled air inside the container.

This flow is affected by the type of package and the mode of stuffing.

The movement of frozen cargo has different requirements for each product. However, refrigerated and frozen cargo is usually separated to control the temperature.

For refrigerated cargo, air must flow through the cargo, removing heat and gas and providing ventilation around the carton. This is because the heat inside the container is not only generated from the outside, but can also be generated by the cargo itself. Let’s look at an example:

Fruits and vegetables. When these foods are shipped, they release heat, water, and gases such as CO2. This makes it important to maintain a constant air flow both around the fruits and vegetables and throughout the cargo. The same is true for many other products.

Refrigerated container

For frozen cargo, the products must be stacked side by side so that there is no gap between the cargo and the wall. This helps keep the food cool. And the air only needs to flow around the cargo and the walls. This prevents the heat from passing through the insulation from the outside and heating the cargo. The heat of the fan motor also needs to be removed.

Continuous atmospheric control and outside air circulation

Food in the reefer container
As mentioned immediately, it is important to maintain a stable air circulation around the fruits and vegetables, as they continue to breathe and release gas.

These breathing gases can lead to cargo damage such as uncontrolled aging, aging and false flavors. Therefore, all refrigerated containers are equipped with an outside air ventilator that removes gas from the container.

The humidity controller automatically “opens and closes” the container to release excess water that can accumulate in the box.

The relative humidity of the air in the reefer container can be especially important in the transportation and storage of refrigerated goods.

Dry air can cause the drying of fresh fruits and vegetables, which can affect the appearance and will definitely reduce the weight at the point of sale.

To ensure that the humidity is accurate, a remote modem uses a data logger that continuously monitors the supply air temperature, return air temperature, ambient temperature, and humidity level.

Description of Pre-Reefer Trip Inspection (PTI)

Reefer’s pre-trip inspection is actually a thorough check of both the container and the machine before shipping.

7 Things You Should Not Include in Container Shipping

This ensures that the chiller works properly in the correct settings (for the goods) and that the container is clean and undamaged.

The specific sequence in the PTA of a refrigerated container will vary slightly from carrier to carrier, but basically includes the following checks:

Before turning on the power:

General inspection (make sure the unit and components are not physically damaged and missing (boxes, contactors, cables, plugs, compressors, loose wires, etc.)

  • Check cleanliness: No extra labels, no cargo debris / debris, etc.
  • Check the refrigerant and lubricant
  • Partlow inspection: Make sure the chart drive is rewound and the battery level is within range
  • Check the electrical insulation value (compressor, motor, heater)

After turning on the power:

Make sure the phase correction contractor is working (voltage measurement and recording)

Engine maintainability check:

Make sure there are no abnormal noise components
Make sure the fan and blower are in the right direction
Start LPPP (CFII), FPT (Smart), LPP (MHI), AutoPTI (Microlink), or FPTI (MPC)
Detect the appropriate working unit when the setpoint is reached
Calibrate the sensor and Partlow element

Preset temperature set to –18 ° C:

Start and verify that the unit is manually defrosted and the cycle is complete
Check the cleanliness of the drain
Record oil level immediately after thawing
When the temperature reaches -18 ° C, the unit is fully cooled and operates.

Compressor pressure measurement:

Measure current (compressor, conditional fan motor, evaporation motor, heater)
Detects the appropriate working unit when the set value – 18 ° C is reached and checks the Freon level
Run with temperature set to 0 ° C – Switch off when temperature reaches 0 ° C
When the unit reaches 0 ° C, record and calibrate the sensor and Partlow element.

Development of the refrigerated container market

According to Drewry, the world’s freezing trade continues to expand. And in 2017, the industry grew by more than 5% to 124 million tonnes.

Containerized refrigerated container traffic outpaced the overall growth of the 2017 marine refrigerated container trade by 8%. Despite the significant weakness of container logistics in 2018, the proportion of refrigerated containers continues to rise by 3%.

Want to buy or lease a reefer container?

There are several companies who are ready to lease reefer containers. You can find top 10 container leasing companies.