A method of installing a mandrel, useful in high voltage cable splicing and termination operations, wherein said mandrel exhibits a tapered surface and longitudinal ribs for assembly onto a high-voltage cable to be connected to a premolded or extruded high-voltage component. As the premolded high-voltage component is passed over the mandrel, the mandrel expands the internal cavity of the high- voltage component and may further reduce the loss of lubrication within the internal cavity of the high-voltage component thereby allowing for the high voltage component to be easily installed onto the high-voltage cable. After the high voltage component passes over the apparatus, the high-voltage component may return to a lesser-expanded shape providing a snug fit around the cable member. The high-voltage component may then compress around the cable, with a uniform layer of lubricant remaining in between interior cavity of the high-voltage component and the outer layer of the cable.