Additionally, a further requirement was to evaluate the fastening options for the mounts into which the various sections of the ladder would rest as it extended upwards when in use: and which would be taking the full weight of users plus any equipment they might be carrying. For this, one bracket was required on each of the upright sections for each of the extended sections to rest in.
There were a number of considerations all in play at the same time in the application and amongst these were the amount of weight that the ladder needed to be certified as safe to carry, the fact that the ladders may spend a considerable part of their working lives in an outdoor environment, and that the aluminium sections being fastened into were thin walled as part of a quest for the overall lightness of each unit.
Bollhoff recommended its RIVNUT blind fastener for the job for a number of reasons. Amongst these was the fact that the fastener had been developed from the outset to provide extremely high pull out strength, that it could be supplied with a number of corrosion-protection finishes and that it was specifically designed for use in thin-walled materials.
Bollhoff’s Clive Brown observed “RIVNUT was well qualified for this application because it ticked all the required boxes for the ladder design team. Most of us make use of a ladder at some point during the year so we fully understood what the manufacturers meant when they demanded that their load carrying criteria needed to be safely met! By delivering fasteners with adequate corrosion protection we also provided satisfaction that the described in-service life could be met: this was deemed vital given the potential costs involved of products being returned by customers in the field”.
