Service Life of K-Line Insulators
K-LINE INSULATORS was formed in 1983. Since then K-Line has had millions of insulators placed in-service world-wide and performing world–wide in varied environments from relatively mild to extremely harsh conditions.
We encourage our Customers to return a few long term performing insulators from lines they are taking down or relocating, etc. for our inspection of the insulator’s condition. From time to time K-LINE INSULATORS receives some of these insulators back from the field and puts them through a few tests that attempt to predict remaining life. Utilizing K-LINE INSULATORS’ technical experience, its expertise and the long time field experience of our insulators gives us some idea of not only the current condition of these units but what might be the remaining life expectancy and longer term performance of those in-service units.
Also, based on our product experience, accelerated life testing and extrapolation of test data we are confident our insulators will perform well for over 40 – 50 years in harsh environments with little or no maintenance. In more aggressive environments, it may be necessary to conduct some selective periodic maintenance after some years in service to further extend the good long term field performance of the insulators. This decision needs to be made in situ for each such location, environmental and contaminated condition and in consultation with K-LINE INSULATORS.
The types of tests K-LINE INSULATORS conduct usually include:
- Visual inspection of the condition of the insulator, looking for any signs of degradation.
- Dry Flashover (this does not usually show much difference when compared to a new unit of the same type)
- Wet flashover (this usually gives us an indication of the effects of the local contamination in the area where the insulators were installed)
- Leakage current levels are measured under wet conditions and give some indication of the contamination conditions in the field location. The leakage current levels of units removed from even heavily contaminated areas are usually very low and at most only slightly higher (in the µA range) than a new unit.
- We also tend to conduct a hydrophobicity check as per the STRI guide. In most cases again we find the field aged insulators to show a very good and high level of hydrophobicity.