What Is a Cooling Element?
A Cooling Element is a material that is used to keep products cool in transport. dometic rv fridge These can be made from different materials and can be shaped to fit the product being transported, so that it can remain in a cooled state for longer periods of time.
Generally speaking, cooling elements have two layers of foil material between which an intermediate layer of liquid-absorbing, vapour-releasing material is accommodated. The two layers of foil material are fastened to one another by means of welded connections such that a compartment is formed between them.
The compartment is in liquid communication with a buffer reservoir via at least one flow restriction.
In some embodiments, the buffer reservoir has a maximal volume that is essentially equal to the maximum liquid volume of the liquid-absorbing vapour-releasing material when this material is saturated with liquid. This allows the cooling element to be filled precisely once, without forming water pockets that could prevent the cooling function from functioning properly for a long period of time.
If the buffer reservoir is larger than the liquid volume of the absorbing, vapour-releasing material, it can also be adapted to provide an even longer cooling function. In this way, the temperature is lowered sufficiently to make sure that the medium temperature does not exceed the permissible temperature limit of the pressure measuring instrument.
Some variants of the patented cooling elements are characterized by the use of additional welded connections between the layers of foil material within the circumference of the compartment. These connections are much more robust and mechanically reliable than glued or stitched connections.
These welded connections are typically rounded at their corners or ends to avoid stress concentrations in the foil material adjacent them, which can lead to the formation of tears. This is a particularly advantageous feature when the welded connections are used to join the two layers of foil material together, as it can be avoided that the edges of the welded connection become folded or crumpled.
The rounded welded connections can be made with an appropriate heat treatment or by means of chemically or thermally bonding the bonded layers to each other. This prevents local weakening and a premature deterioration of the overall structure of the cooling element during use, and can result in a more attractive appearance as well.
This technique is also suitable for cooling elements that are positioned in contact with sensitive and potentially hazardous substances. In these cases, the welded seams can be secured with a suitable coating, preventing the material from oxidising or otherwise changing its properties under high-temperature conditions.
In addition, a cooling element may be manufactured with a number of welded seams in any position as desired. This can be done in conjunction with a suitable heat-treatment process, for example an acid-etching or an electrochemical deposition.
Alternatively, the welded seams may be secured by means of a special welding procedure. For instance, this can be done using a laser. This laser welding technique can be very precise and provides the advantage that the welded seams are able to be produced in a shorter time than conventional methods.