The German Institute for Underground Infrastructure (IKT) has released the cured-in-place pipe (CIPP) liner report for 2018.
For 15 years, IKT has been testing the performance of CIPP liners, reviewing the trends in improvement and reporting the results of the previous calendar year.
During that time, approximately 23,000 samples taken from installed CIPP liners in sewers have been tested, representing samples from 2–2.5 million m of rehabilitated sewers.
The 2018 LinerReport includes more than 2,100 liner samples, taken at installation sites in 2018 for quality control purposes and examined by the IKT testing laboratories.
For the report, four test criteria are evaluated: modulus of elasticity, flexural strength, wall thickness and water tightness.
In each case, performance has been determined by comparing the test results with the expected target values derived for each sample from the relevant product approval or client information.
The results showed that the average proportion of passed tests results for the four test criteria remained at a high level in 2018 – with mean values of 98.9, 97.5, 97.4 and 94.1 per cent respectively – similar to the previous year‘s level.
There was a very small improvement in the modulus of elasticity and very small declines in the other three criteria, meaning 2018 was a good year overall for liner quality.
Of the 1,366 samples with data for all four criteria, 90 per cent met the requirements for all four test criteria; one tenth failed at least one test criterion.
This year, five lining companies made it into IKT’s ‘100% Club’: Bluelight with PAA-F-Liner; Hamers Leidingtechniek with Alphaliner; ISS Kanal Services with Alphaliner; Jeschke Umwelttechnik with Alphaliner; and Kanaltechnik Agricola with Brandenburger Liner.
Looking back over the last 15 years, IKT noted a trend of improving quality over about a decade until 2013–15, before stabilising
Since 2015, there has been a slight tendency for a decline in performance against the mechanical test criteria.
This does not necessarily reflect a decline in quality assurance, with IKT offering a number of possible explanations for the drop.
This includes an intensive struggle by the lining companies for market share in a price competitive market, the development of new machinery and plant capacities; the entry of new market participants; and a shortage of skilled workers, particularly in the commercial sector.
For more information visit the IKT website.
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