The two photos below are sealed test tubes that were both prepared in September 1995 (now 13 years old), you can see from the condition of the corks that these are of the age claimed.

 

Both test tubes had nails pushed through the corks and they both had water introduced. The one shown below had no VPI added. You can see from the picture, that the nail has massive corrosion and shows expansion though corrosion of approximately 300%, losing most of its structural strength. This physical expansion through corrosion is exactly what happens to internal rebars within concrete structures.

 

 

The nail below was sealed on the same day in September 1995, but had a very small amount of our VPI 580 added to the test tube. You can see a small amount of surface rust, but there is actually a patch on the nail towards the tip that is still shiny, showing no corrosion at all. Not bad for 13 years on!!!!!

 

Very importantly, the steel still shows limited signs of corrosion, despite the original sample of VPI580 no longer being in the test tube. This IMPORTANTLY proves that there is a coating on the nail.

 

 

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We have recently started some new tests on our VPI580 product on the 17th May 2007

 

We sealed 2 identical sterile sample jars, both with steel nails in, we have added tap water to both jars, 1 jar has no VPI and was sterile when the test was started, the other was also sterile, but has a small amount of VPI suspended in the jar. We will be taking pictures at frequent intervals to show the resulting outcome. Here are the Day 1 pictures;

 

 

Both nails above show no visible signs of corrosion on day 1 - 17th May 2007

 

Below is the picture taken after 4 days on the 21st may 2007. The sample without the protection of VPI (sample 1) already shows surface rust on the tip of the nail, it shows the water has discoloured through the corrosion and the jar has large amounts of condensation which is also apparent on the nail. The sample with VPI (sample 2) shows no sign of rust and no condensation.

 

 

Below is the picture taken on Monday 4th June 2007, (Day 18) (it shows much more corrosion on the sample with no VPI)

 

 

 

Below is the photo taken on 19th June 2007 ( Day 33 ) It shows further corrosion on the sample without the VPI, whilst the sample with the protection of the VPI is no different to the day it was prepared.

 

 

 

 

Below is photo from 8th August 2007

 

 

 Below is the picture from 28th August 2007 (Day 103)

 

 

 

 Picture below taken on 27th Feb 2008- approx 280 days after the test was started

 

 

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We recognise that the above nail tests show the effectiveness of our VPI product protecting steel from corrosion, our new cube tests will demonstrate how far VPI vapour moves through concrete.