In order to fill the cavity without bubbles, RPC injects the liquid POWERSIL® Gel C 670 into the composite hollow-core insulators from below. To do this, the gel is added under slight excess pressure and is thus already compressed to some extent. “With a precisely metered excess pressure, we provide additional assurance that the gel will always snugly fit the form of the pipe wall, even in the depths of a Siberian winter,” explains Merten. After the gel is filled, it cures at room temperature within approximately eight hours.
As a soft and compliant material, the compressible gel offers the embedded fiber-optic cables optimum protection against external mechanical influences. For Merten, one thing is certain: “In our new, special composite hollow-core insulators, the fiber-optic cables are locked up safe and sound. In POWERSIL® Gel C 670, we have found the ideal potting compound to suit our needs.” Under its POWERSIL® trademark, WACKER offers special silicones for transmission & distribution applications – alongside silicone gels, these include elastomers and silicone coatings.