Rollanodes anodes are designed for installation in pre-drilled holes in an existing concrete structure. The electrolyte is sandwiched between the zinc layer rolls to give sufficient current capacity with additional electrolytic paste added around the anode to maintain electrical continuity within the concrete (The anode diameter is 25mm and available in lengths from 100mm to 1m).
Rollanodes are utilised in those areas where a high expectancy of corrosion is likely. They guarantee a strong reduction of corrosion and prevent new locations from corroding in the future.
Bridge or viaduct beam supports and columns
Zones of newly cast concrete on an existing structure
Balcony facings and concrete facades
Rollanodes anodes are specifically designed for application in pre-drilled 30mm (minimum diameter holes to a depth corresponding to the anode length + 4-5cm.
Specifically for this type of application, a Zinc Activator Paste (ZAP) has been developed for easy installation (supplied in 600 ml flex packs).
ZAP is used to fill the space between the anode and the drilled hole to ensure a durable and intimate contact between the galvanic anode and the concrete enabling ionic current flow. The ZAP can be applied with a standard manual or battery powered sealant gun. The formulation is such that it establishes a durable ionic conductivity even in very dry conditions and makes it possible to easily replace the anodes at their life end.
The operational service life of the anodes is directly related to the following variables:
total zinc weight per unit of surface area
steel surface area (steel density)
presence and availability of oxidising agents (O2, H2O) to maintain the cathodic reactions
on the steel structure
The eventual driving force between the anode and the steel reinforcement guarantees a long and corrosion free service life for the structure.
Thanks to the ease and speed of installation, costs can be reduced to a minimum and when the anodes are installed with ZAP the locations can be finished off with a mortar to minimise moisture ingress. Finally a plastic cap can be used to seal the hole in the event that the anodes need to be periodically monitored.