When it comes to shipping containers, it’s really not a case of one size fits all. There are various different types of container designed to meet the transportation needs of different types of cargo, so you can ship your goods with confidence. This guide looks at the reefer container – a temperature-controlled container typically used for shipping perishables such as food and drinks. Read on for all you need to know about the reefer.
What is a Reefer Container?
A reefer, short for a refrigerated container, is a shipping container designed to maintain the temperature of its cargo, typically used for shipping perishables. The name can be misleading as the reefer is not actually intended to reduce the temperature of the stowed goods – instead, the cargo should be pre-cooled to its optimum temperature before loading. T-shaped metal bars on the floor of the container (known as a T-Floor) distribute air set at the appropriate temperature around the cargo for effective temperature management.
When Should I Use One?
Reefer containers are used to stop perishable items, such as food, drink and flower bulbs, from spoiling. They’re also used to transport medicines, pharmaceutical items and chemicals that need to be kept at a certain temperature. Cargo can be chilled or frozen, and reefer containers can also be used to maintain temperatures warmer than those outside.
Types of Reefer Container
The different types of reefer container available include;
- 20’ Standard – maintains temperatures between -30 and 30 degrees.
- 40’ High Cube Standard – maintains temperatures between -30 and 30 degrees.
- 40’ High Cube Controlled Atmosphere – some goods, including some fruit and vegetable produce, require controlled atmosphere transit. This involves an injection of nitrogen to achieve the correct oxygen and carbon dioxide levels inside the container. Maintains temperatures between -30 and 30 degrees.
- 40’ High Cube Deep Frozen – maintains temperatures as low as -60 degrees, and is used to transport frozen goods.
- 45’ Pallet Wide High Cube – maintains temperatures between -35 and 30 degrees. The dimensions of this reefer make it ideal for transporting goods on euro pallets.
Insulated containers with integral refrigeration machinery (refrigeration units) know as integrals are most commonly found. Some insulated containers, known as port hole or con-air containers, have external refrigeration sources, but these are less common and likely to be gradually phased out.
Can a Reefer Container Chill Cargo?
Reefer containers are not designed to be used to reduce the temperature of their cargo. Although this will happen in the case of warmer cargo, it may not happen quickly enough (especially to the goods below the surface layer of cargo) to prevent it from perishing or spoiling.
The Defrosting Process
This occurs periodically to remove the layer of ice that may form on the unit’s evaporator coils. During defrosting, the unit’s fans are turned off automatically so that no warm air enters the cargo compartment.
The Inspection Process
Integral unit containers are required to have a pre-trip inspection, arranged by the carrier or his agent, to ensure that the refrigeration units are working correctly. This must be carried out by a specialist engineer and usually takes place in the port area. Cargo should also be inspected for any signs of damage before loading.
The Correct Stowage Method
Stowing items correctly in a reefer container is important, as the air needs to flow around the cargo in a particular way. Cargo should be kept below the red load line and should not be loaded beyond the end of the T-floor. The refrigeration machinery should always be switched off when the container doors are open.
It’s recommended to take advice from a specialist to ensure correct stowage – an experienced freight forwarder like John Good Logistics can take care of all aspects of shipping and answer any questions you might have.
Cold Treatment Shipments
Some types of fruit require cold treatment to kill potential pathogens. This involves them being kept at a lower temperature than usual, which is monitored by the insertion of steri probes into the fruit. Cold treatment shipments are also known as Steri Shipments.
Sealing a Reefer Container
A seal noting the serial number of the shipment is attached to the reefer container after loading. This number is also recorded on the relevant shipping documents. The seal is then inspected on the container’s arrival at its destination to confirm that the cargo hasn’t been tampered with during transit.
Malfunction of a Reefer Container
Reefer containers contain temperature sensors, which will register any temperature fluctuations to indicate a problem or malfunction. Ensure that any reefer container you use has undergone stringent testing, and check whether there is a backup refrigeration unit in operation to avoid any in-transit disasters.
John Good Logistics is experienced in arranging the transportation of temperature-controlled cargo – so put your perishables in the safe hands of a shipping specialist for ultimate peace of mind.