Middle East Query – Rejuvenation Impact on Conductor Shield
Dweller of the Desert asked 22 questions in his post …
In this installment I address question 9.
9. Will the injection affect the semicon around the conductor, since the fluid will penetrate through it?Semi-conductive shields are carbon-black-filled polymers. Typically the carbon-black loading is about 50%. Electrons flow through the carbon black, because the conductive carbon black agglomerates are physically touching each other. The polymer in between the agglomerates is a dielectric.All rejuvenation fluids are quite soluble in the strand-shield. Of course, part of that solubility is because the fluids diffuse into and through the amorphous portions of the polymer. To learn how that happens, check out my 15-March, 2011 post “Chain Entanglement.” Even more significant than diffusion through the polymer portion is transport though the carbon black agglomerates. In the diagram nearby nano-me (my nano-sized alter ego) demonstrates the morphology of the carbon black at greater and greater magnification. Carbon black has a great deal of volume in micro-sized and nano-sized holes and pores that provide flow paths for fluid transport. Novinium fluids are selected and tested to verify that they have no detrimental effect on cable materials. Upon exposure to Novinium dielectric fluids there is a slight increase in the resistivity of the conductor shield, but well within the IEC and ICEA conductivity specifications. The typical increase is on the order of 1% of the ICEA S-94-649 2000 specification. The agglomerate-to-agglomerate electrical connections are not perturbed in a substantive way. Novinium® Ultrinium™ fluids include high dielectric constant stress grading components.High dielectric constant conductor shields are used by at least one EPR cable manufacturer. Ultrinium fluids improve the dielectric performance of the cable system including the conductor shield.
For now, Ma’a salama (معالسلامة/Good bye)
Electrons flow from agglomerate to agglomerate. The electrical connection between agglomerates is not changed by the introduction of dielectric enhancement fluid. The pores and convoluted surfaces of the carbon black facilitates the permeation of fluid through the shield.