A novel type of synthetic paper for use in ehv underground cable insulation

Of the possible synthetic substitutes for cellulose cable insulation previously reviewed by Fujita
¹
and Reed,
²
Tenax
^R
paper
³
development was discontinued for economic reasons, while kraft/polypropylene (PP) film laminates have been successfully applied to experimental 132 kV
⁴
and 275 kV
⁵
cables. The se laminates have mechanical properties which permit satisfactory taping; however, the PP film involved tends to partially dissolve or swell in hydrocarbon imprégnants. This compatibility problem was noticed on lapped insulation after being subjected to load cycling.
⁶