STAINLESS STEEL CABLE CLEATS – PREVENTING GALVANIC CORROSION OF CABLE FIXINGS
In the following article we provide an evidence based specification case for stainless steel cable cleats where levels of atmospheric corrosion preclude use of other cable fixing materials.
Using this criteria, if galvanised ladder is the support structure, and there are no other significant factors, it is safe to use ball lock stainless steel cable tie. However, if the support structure is stainless steel, separation should be provided if aluminium or galvanised cleats are used.
Should you require any further assistance in the selection or specification of stainless steel cable tie, MV Medium Voltage or HV High Voltage cables please do not hesitate to contact us.
The corrosion resistance properties of stainless steel are a result of chromium, which reacts with oxygen and forms a self-healing impervious layer of chromium oxide on the surface of the steel.
In most circumstances the chromium oxide layer is extremely durable and helps in resisting galvanic corrosion. However, in certain installation locations, such as railway tunnels, the oxide layer can be continuously penetrated.
This occurs due to trains frequently applying their brakes, which releases mild steel dust into the atmosphere that then settles on the stainless steel. If moisture is present, then corrosion occurs at an exaggerated rate. In such circumstances, if regular washing is not feasible, use of aluminium as an alternative to stainless steel products and/or coating processes are strongly recommended.
Ellis Patents offers special coatings to suit specific cable installation environments – e.g. our London Underground Approved electrostatic plastic coatings.
CABLE CLEAT FIXINGS
Closure fixings on cable cleats are fundamental to the loop strength of the cable cleat and its short-circuit withstand capability.
All Ellis Patents 316L stainless steel cleats use 316 fixings, which are manufactured to a precise and specific tensile strength. Fixings are sourced directly from approved manufacturers and any fixing on any cleat is directly traceable back to the batch quality records at that manufacturer.
GALVANISED STEEL
Contracts often require a guarantee regarding the life expectancy of a cleat. If the installation is designed correctly and all other corrosion issues have been considered this is a relatively simple exercise for wing lock stainless steel cable tie. With galvanized steel, life expectancy is determined by the thickness of the zinc coating.
