This blog is a summary of test results of some of our thermal covers. This will help when deciding which thermal cover is the best for your requirements.
The covers that we tested are shown below.
| |
Double sided thermal foil cover | White thermal pallet cover | |
| Black quilted fibre fill pallet cover | Foil fibre fill pallet cover (no base sheet) |
This test is an ambient temperature test. It does not give any indication of the thermal effectiveness of these covers when exposed to radiant energy from direct sunlight.
The palletised loads consisted of double wall cardboard boxes containing bottles of water placed on a standard 1200 x 1000mm pallet. For each test the thermal covers were applied to the test load as per standard procedure.
Twelve corrugated boxes were each loaded with forty eight (48) 500ml water bottles pre-conditioned at a temperature of between15ºC to 17ºC for 12 hours.
Four of the boxes had a temperature data logger placed inside and these were placed at different locations on the pallet. Where the foil cover had a base sheet, it was placed as shown below.
The test loads were placed inside a controlled environmental chamber at an average ambient temperature of around 48ºC for 20 hours. A temperature data logger tracked the temperature inside the environment chamber.
The detailed test results are available on request, but here are some graphs showing a sample of the test data.
The data we are interested in are contained in the two dark grey columns in the table below. They both tell us the same thing but in different ways.
The dark grey column on the left tells us how many minutes it took for the temperature of the water to increase by 1°C on average.
The other grey column tells us how much the temperature increased every hour on average.
| Average time taken to increase the temperature by 1°C | Average ambient temperature (°C) during the test | Starting temperature of load (°C) | Per hour temperature increase (°C) | |
| Double sided thermal foil cover | 61.98 minutes | 48.7°C | 17.8°C | 0.95 |
| White thermal pallet cover | 76.64 minutes | 48.7°C | 17.3°C | 0.9°C |
| Black quilted fibre fill pallet cover | 100.42 minutes | 48.7°C | 15.3°C | 0.56°C |
| Foil fibre fill pallet cover (no base sheet) | 133.33 minutes | 0.45°C |
So this table shows the least effective at the top, and most effective at the bottom.
These test results are obviously not real world data, but they give us some comparisons to work from.
If palletised load are exposed to direct sunlight (infrared radiation) this will increase the temperature of the external parts of the load very quickly even if the ambient temperature is low.
As foil or MET PET (metalised polyethylene terephthalate) reflects 95% of radiant thermal energy, this virtually negates this risk.
The black quilted thermal cover is more effective than the double sided thermal foil cover in this test, but would perform less effectively when exposed to direct sunlight.
There are temperature standards for transporting frozen, chilled and ambient goods and you will need to consider the various parameters of temperature range, length of journey, and method of shipping before deciding the best way to transport your temperature sensitive goods.
These thermal covers can be used with gel ice packs to maintain low temperatures for longer periods of time.
This blog will give some indication of the effectiveness of different thermal covers, but trials will have to be carried out to ascertain the best solution for your requirements.
We can help you guide you towards the best way to protect your goods in transit so if you have any questions please get in touch.