A sharp drop in temperature, coupled with high relative humidity, creates moisture that can seriously harm cargo during storage or transportation.
Polythene and pallet-wrap will not prevent water vapour penetration – transmission rates are very high through this type of packaging.
Desiccant (usually silica gel sachets or activated clay bags) adsorbs moisture produced by temperature change – typically experienced in shipping where goods are exposed to high daytime temperatures and very low night-time temperatures over several days, if not weeks.
Desiccant Dehumidifier
Sufficient desiccant must be used as part of a total humidity control system. The type of product, the packaging employed, and how it is stored will all influence the amount of desiccant and the type of desiccant to be used. Used correctly, it will extend shelf-life for your products.
Shipping containers themselves behave like large iron lungs whilst at sea–taking in warm, humid air in the daytime and cold air at night. Moisture in shipping containers has always been a big problem. Often referred to as “Container Rain”.
Desiccant
R-Tech supplies specially formulated desiccant strips with hanging hooks specifically for this application. 6 strips will protect a sealed 20ft container – 12 strips in a sealed 40ft container, for a period of at least 6 weeks. The product is highly adsorptive but stays dry at all times.
R-Tech will be happy to discuss requirements for your particular shipments or projects with you should you wish to contact us.
If goods need protection for long periods, we strongly recommend creating a closed environment using a special barrier foil developed specifically to protect against water vapour transmission. We can supply foil “bags” or “covers” of any size with a detached lid, (or base), that can be heat sealed to close the pack after the goods have been packed into it and desiccant added. The desiccant will dry the air within the cover/bag and because it is impervious to penetration by new air or moisture, the goods will sit in a totally protected environment until the cover/bag is opened.
Foil covers can be made as big as a shipping container if necessary! The bag is inflated inside the container after being supplied flat. The base can be driven over while loading because it is composed of a durable foil.
These foil covers even have the option of having a clear viewing “window” to prevent customs from opening the package and ruining your humidity protection! For more information on the range of barrier foils available, go to: Foil Rolls, Bags & VCi.
