LAPP provides cabling for vaccine refrigeration

Cables and connector systems are a vital link in high-performance refrigeration systems required by industries such as food and beverage, chemical, medical, scientific and advanced logistics and shipping companies.

L&R Kältetechnik (L&R) produces refrigerating systems for exceptionally low temperatures encountered in the chemical and pharmaceutical industries. L&R was asked by the German manufacturer of a COVID-19 vaccine, Biontech, to assist it with the bulk transportation of millions of doses at a time of its vaccine following approval for its widespread use.

The vaccine has to be stored at -70°C and only tolerates standard refrigerators for a short time before being administered. Biontech supplies the vaccine in boxes that act like large Thermos flasks, keeping the content cool for several days, but what can logistics companies do if they want to send the vaccine in containers by air or ship, where transportation takes longer?

L&R came up with idea of taking a conventional shipping container with a length of 6 or 12 metres and installing a refrigeration chamber, including cooling and even an autonomous emergency power supply with a diesel generator or liquid nitrogen — and ensuring everything has a backup in case of failure.

A standard 12 m-long container can hold a 40 m³ refrigeration chamber with a temperature of -80° and a preliminary chamber at -20°, which acts as a low-temperature airlock. The storage area is estimated to have a capacity of up to 3.5 million vaccine doses.

For such low temperatures, transport companies normally have to use dozens of laboratory deep-freeze cabinets, which are not only expensive, but require significantly more power and space.

Hot and cold

The cables used to make this container application possible have to withstand harsh conditions in the form of extreme temperatures, both cold and hot. Failures could not only cost valuable product, but even lives where temperature ranges of -70°C and more are involved.

When designing the containers, L&R chose LAPP Australia’s parent company to supply the necessary cables to work within the extreme temperature challenges presented.

For example, the refrigerant flows through the evaporator at a temperature of -90°C. Fans ensure that the heat is dissipated. To prevent their electric motors from freezing, the bearings are heated. The two compressors have a power of 20 kW each, and currents of 40 A flow through the ÖLFLEX Classic 110 cabling. Directly on the diesel generator, the temperature can rise to over +100°C.

In the icy storage compartment, meanwhile, the temperature can be as cold as -100° in some places, ÖLFLEX HEAT cables with a PTFE sheath are installed, since they are not only chemical resistant, but can withstand temperatures from -190 to +260°C.

Heating for lights and door frame

In addition to the power cables in the cooling system, the container also contains signal transmission cables; for example, from the temperature sensor that controls the frequency converter and thus the compressor. In addition, the operator can connect a data cable into the control cabinet at a customer interface.

There are also some cables that are not responsible for cooling, but for heating. When you switch on a light at home, it should not be covered so that the heat can dissipate. In the vaccine store, the problem is precisely the reverse. In this case, the LED light strips actually need to be heated because otherwise they could fail in the cold.

Another problem is the rubber seal on the door between the lock and the storage chamber, which could freeze immediately, leaving any person inside trapped and quickly in mortal danger. As a result, there is heating on the door frame and door contacts to monitor when someone enters the chamber.

Any person present in the low-temperature section of the container has to press a button regularly. If there is no signal, the person may have fallen unconscious and an alarm is triggered. Any fault in the electrics could cost lives, which is why L&R Kältetechnik chose wide-temperature data and control cables from LAPP.

“In our quotations we not only specify the properties of the cables but also that they are ÖLFLEX cables from LAPP and which type,” said Christoph Wiemer, Head of Special Systems Sales at L&R Kältetechnik.

Image: L&R Kältetechnik container innovations for COVID-19 vaccines include LAPP OLFLEX HEAT 260SC cables engineered for the most extreme application requirements.