MIDDLE CLOSURE thermal cover for insulating pallets

The insulated thermal covers with middle closure are used to preserve or stabilize the temperature of the products, which are protected by the thermal cover, as long as possible. The time that the temperature can be preserved of stabilized, or the speed of temperature increase or decrease, is depending on the insulation quality. Thermal covers or insulated covers with middle closures are manufactured with a certain Temax insulation material which have a certain insulation quality (R-value or U(k)-value). The higher or thicker the insulation quality, the longer the time of temperature preservation or the slower the speed of temperature change of the products inside the thermal cover.

Next to the insulation quality of the thermal cover with middle closure, the stability or deviation speed of the temperature of the product is also depending on the presents of open thermal bridges or open cold bridges on the thermal cover and packaging set-up. Open thermal bridges are locations in the design or set-up of the thermal cover where an external convection flow (air flow) can exist which has a very big impact on the speed of temperature change. It is therefore very important that open thermal bridges are avoided at all times.

When conditioned or time-temperature sensitive products are protected from external temperature influences with a passive cooling systems such as thermal covers with middle closure, the goal is to purely use the available thermal energy of the products to maintain and stabilize the temperature of the products as long as possible. As we know, the result of this stabilization is depending on the insulation quality of the thermal cover combined with possible convection flows and the thermal energy of the products combined with the temperature difference (inside-outside). If the temperature cannot be maintained according to the preferred time-frame, the time can be extended by increasing the available thermal energy. This extra energy can be generated by all kind of passive cooling systems such as gel packs – ice packs – dry ice – PCM’s Phase Change Materials.

Most pallets have bottoms which are not completely closed so a convection flow (air flow) can appear meaning that the air can flow through these openings. Therefore it is very important to seal or insulate the bottom of the pallet before loading the chilled or frozen products. An insulated bottom will increase the temperature results significant. To insulate the bottom a on-way use insulation or cardboard can be used.