Hot dip galvanising is carried out in baths of almost pure zinc, but, as in steels, some other elements are added (like aluminium, lead, nickel, copper, tin, bismuth, etc.) that modify certain physico-chemical characteristics. Numerous academic studies and the experience of a galvaniser lead to the use of different mixtures to achieve greater coating brightness, greater smoothness of the molten zinc, greater ‘indifference’ to the silicon content in the steel.
Hot-dip galvanising has no differentiation in colour: its tone varies from bright bluish-grey to dark matte grey depending on the base material, the bath composition and the thickness of the coating. The ‘coloured’ galvanising mentioned above are electrochemical galvanic deposition treatments, and the different colours in this case are caused by the electrolytic solution used and working process.
The mobile tunnel’s supporting structure is made of hot-dip galvanised steel, calculated in accordance with current steel construction regulations in relation to the installation area, complete with certification signed by a qualified technician.
The cover is anchored on the ground using sliding rails of adequate size, which can be, depending on the circumstances, either dowelled into the ground (with a 250 mm thick concrete floor) or sunk into the concrete pour on a curb or directly at street level.
The tarpaulin has a coupling system between the fabric and the structure characterised by plates thermally welded with frequency machines, complete with straps in tear-resistant material. At the most stressed points, the fastening is carried out by means of thermo-welded bands equipped with steel rings for the entire width of the truss. This system allows us to safely assemble our structures even in highly windy areas.
The contact points are reinforced with a double layer of tarpaulin to prevent the mantle from wearing out.
The structure’s sliding is guaranteed by solid steel wheels with self-lubricating anti-water and dust-proof double ball bearings so that the tunnel can be moved at any time. The wheels are also covered by special accident-prevention guards that guarantee absolute safety for operators and goods.
The nature of the material itself and the technical/chemical characteristics of PVC ensure its TOTAL impermeability to water and weathering.
PVC, by nature of its components, provides excellent resistance to fabric bending.
PVC has a fire rating of 2, thanks to the special layers it is made of.