Abstract: A cylindrical porcelain insulator having a depressed opening in at least one end thereof is utilized as a support member. An elongated steel stud having a threaded end and an enlarged securing end is disposed in the depressed central opening of the porcelain insulator. The enlarged securing end has circumferential lateral ridges and depressions for providing an enlarged surface area. Babbit or epoxy material is disposed in the remaining volume of the depressed opening. The securing end of the stud is therefore suspended in the hardened babbit or epoxy material, which in turn is affixed to the sides of the depressed opening, thus affixing the stud to the insulator. The stud has a relatively flat circumferential lateral shoulder at the upper end thereof which protrudes above the end of the insulator and out of the depressed opening. An electrical bus bar or bus bar retaining apparatus is disposed around the threaded portion of the stud to rest on the flat shoulder in a flat surface to flat surface relationship.

Abstract: A metal-enclosed switchgear characterized by a metal enclosure having a rear wall, opposite side walls, a bottom wall, and a front opening with a door therefor. A circuit breaker is removably located in the enclosure and comprises a plurality of arc chutes and an electrically insulating barrier wall on each side of and spaced from each arc chute. In addition, the metal enclosed switchgear comprises stabilizing means for increasing their natural frequency and preventing relative motion between adjacent components of the enclosure and the switchgear in response to ambient vibratory forces which means comprises first spacers of electrically insulating material in the spaces between each arc chute and each adjacent barrier wall, second spacers of electrically insulating material mounted on each opposite side wall and in the space between the side wall and the adjacent barrier wall.