In case of negative pressure where large movements are foreseen or along the three reference axes (axial, vertical, lateral) – it might happen that the expansion joint, sucked inward, interferes with the metal parts (in particular the baffle), thereby causing:
- possible internal lacerations caused by contact with sharp objects;
- transmission of the baffle surface temperature by conduction on the inner wall of the expansion joint.
Furthermore, in an external concavity, without adequate external protection, debris, rain water, etc.
The installation of a Isolmat bolster bag, inside the expansion joint, provides a valid support that avoids the above mentioned phenomena.