Testing Cable Protection for Marine Environments
Cabling in marine and offshore applications is typically exposed to some of the harshest operational environments. With the damaging effects from UV radiation, potential water ingress and salt spray conditions to name a few, it is vital that this cabling is suitably protected, and due consideration is paid when specifying and installing protective conduit systems.
However, many operators may be unaware that their conduit systems and fittings have not been specified correctly – especially in relation to the effects of exposure to corrosive salt water.
This heavy corrosion can result in system failure and the exposure of cables, which can have a significant impact on operational performance and uptime – not to mention profitability.
Corrosion is a process of deterioration within metals caused by chemical reactions with the surrounding environment. Metals with low or no chromium will naturally corrode and deteriorate due to long-term exposure to moisture naturally present in the air, and this process can be accelerated by exposure to certain properties and environmental factors. It can affect the electrical system, potentially compromising electrical reliability for wired terminations, leading to increased resistance and electrical system faults.
Metallic, flexible liquid-tight conduit systems are frequently used as an effective means of cable protection, but if incorrectly specified could contribute to potential system failure. Cable protection is often overlooked with the lowest cost option specified, resulting in a false economy when considering whole life costs.
Salt Spray Testing
One means of assessing suitability for the demands of the marine environment is to conduct salt spray testing to check the product and surface coating performance. This involves atomising a salt water solution inside a closed chamber, producing a corrosive atmosphere of dense salt water spray at 35 degrees Celsius.
This environment is intentionally harsher than typical sea water hazards, and provides accurate comparative indications of performance in marine environments. The testing is governed by two major standards, ASTM B117- 11 and BS EN ISO 9227 NSS.
However, these standards do not establish how long products exposed to salt spray testing will perform in service. Corrosion resistance varies between different materials and products, leading to unsuitable cable protection systems being specified. So how do you know how effective or how much corrosion resistance a product will offer?
To provide appropriate protection assurances, Flexicon, for example, subjects its products to 1000 hours of standardised salt spray testing. Despite this corrosive test, Flexicon’s SSU, FSS, LTPSS and FPRSS conduits, together with C-SS stainless steel fittings, endure only minimal corrosion and are not compromised.
All these systems are manufactured using Grade 316L stainless steel, which helps reduce the corrosive effects of chlorides in salt water. Also known as marine grade stainless steel, Flexicon uses Grade 316L as standard for its stainless-steel conduits and fittings, further ensuring market-leading performance.
For further information about corrosion resistance performance, the effect of salt spray on different metallic products and support and guidance regarding protecting vulnerable cables for marine vessel applications, please contact:
+44 (0) 1675 466900