HUMIDUR® ME'S DIFFUSION TIGHTNESS IS PUT TO THE TEST WITH ION PERMEABILITYFor the first time in the hydropower sector, the quality assurance measures onsite included a new test method for the diffusion tightness. Moreover, for the renovation of the corrosion protection in the Penstock pipelines of the hydropower station at Wehr, Germany, – more information will follow shortly – substrate-free coating films of Humidur® ME were produced. At the same time as the Humidur® coating application to the pipelines a one-layer as well as a two-layer coating film were applied to a non-adhering foil. After curing, the coating films were sent to the laboratories of engineer Peter Heinze (Germany), in order to investigate the ion permeability of the coating films. The ion permeability test is a new method to measure in a quick way, with evidential results, the diffusion tightness and consequently the effectiveness of a coating as a corrosion protection. The smaller the ion permeability (IP) and the lower the value of the constant CI, the better the corrosion protection of the coating. The constant CI is a reference value that does not depend on the layer thickness. The diagram below shows the test results of : - the blue one-layer coating Humidur® ME on the pipeline in Wehr and - the two-layer coating Humidur® ME, one blue and one yellow, compared to several conventional coating systems. The one-layer as well as the two-layer Humidur® film reveals an essentially lower permeability for ions and therefore a higher diffusion tightness. Consequently, the corrosion protection by Humidur® compared to the other coating systems is expected to be considerably better.
Description of the tested coating materials : Sample 1 Epoxy -coaltar combination, solvent free, two layers Sample 2 Epoxy - coating material, solvent free, two layers Sample 3 Epoxy - coaltar combination, solvent free, water emulsifying, four layers Sample 4 Epoxy - coating material, containing solvent, four layers Sample 5 Epoxy - coaltar combination, low solvent content, four layers UWW 1 lb Humidur® ME, one layer UWW 2lby Humidur® ME, two layers Once more, these results confirm the excellent anti-corrosion properties of Humidur®. For this project as well, a very long lifetime of the anti-corrosion protection is to be expected. Further information about this project and references in the hydropower sector can be found on the website of Acotec: http://www.acotec.be/ or on the website of Corro Tec : www.corrotec.at. With consent of engineer Peter Heinze, PH Ionenpermeabilität, Germany and Schuckseewerk AG, owner of the Wehr hydropower station, Germany. | 
