Wednesday, 20 November 2013


As this Blog is relatively new - and because part of what we hope to do is keep everyone informed on the latest developments with Alocit and Enviropeel - I will be posting one or two updates that relate to events from earlier months.


Everyone in the industry understands this test - you take a sample and subject it to the most corrosive environment you can create, do it for as long as you can - and see what happens.  In the warm, salty and moist environment of a hot salt fog cabinet, unprotected steel will rust right in front of your eyes - and keep on rusting until it is an oozing pile of sediment, without form or structure.

Zinc-plated bolts after 18 months offshore
The main problem with the test is that it is in real time - you might test a zinc-plated bolt for a 1000 hours - but that is 42 days and a long time to wait for a test result.  Yet, while this is a widely accepted test period, it is still very short when you consider what these bolts have to put up with in the real world, where DNV testing has shown that such bolts may fail in 18 months in an offshore environment.

We recognised this when first testing Enviropeel, back in the 1990s. Samples were tested for 3000 hours - said to be the equivalent of 30 years in an offshore environment. The Enviropeel-coated samples passed without a blemish but, 15 years later, it seemed like a good idea to try an even more severe test over an extended period - the first to be 4500 hours.

188 DAYS LATER ...

So, in early 2013, a number of samples were placed in a large hot-salt fog chamber and testing commenced. After more than six months (longer than NASA will take to get a manned flight to Mars), the first sample was removed to see the results. The other coated samples were left in the chamber - the next to be removed when NASA might have reached the outer limits of the Solar System or after a year - whichever comes sooner!

For complete details of the test you can follow this link but a picture is worth 4500 words - and, as you can see, the difference between the Enviropeel-protected bolt and its less fortunate companion is quite startling. With no deterioration of any kind on one and a definite case of man flu on the other - it's easy to see why Enviropeel makes so much sense when it comes to protecting bolted systems.

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