A method for replacing an electrical suspension insulator on a tower having insulator-supporting, and high voltage energized electrical conductor-supporting, davit arms using a helicopter and at least one lineman, said insulator being supported by insulator support plates attached to said davit arms and a conductor being supported in a conductor shoe attached to a lower end of said suspension insulator, comprising the steps of:
- mounting an elongate, non-conductive board having inner and outer ends to said tower with an inner end adjacent said tower, said board being mounted sufficiently below the davit arm supporting the suspension insulator to be replaced to allow the at least one lineman standing on said board to reach said davit arm, said board including upstanding elongate side panels for defining between said side panels and with an upper surface of said board a track, said board having a length at least one foot longer than said davit arm;
- mounting elongate, non-conductive, length-adjustable strut means having inner and outer ends to said tower with said inner ends of said strut means adjacent said tower and the outer ends of said strut means attached near the outer end of said board, an inner end of said strut means being mounted sufficiently below the board for providing diagonal bracing support therefor;
- operating said length-adjustable strut means for positioning said board horizontally and for maintaining said board horizontally positioned on said tower;
- supporting an elongate, non-conductive slider in said track for movement between inner and outer ends of said board, said slider including a planar surface parallel to said upper surface of said board and slider or roller means for facilitating movement of said slider along said track, an upper side of said planar surface including jack means rigidly mounted thereon, said jack means including a piston means vertically reciprocally movable therewithin, and conductor lifting means rigidly connected to said piston means for engaging said conductor;
- using a non-conductive stick,
- pushing said slider along said board until said jack means and said conductor lifting means are positioned directly underneath the conductor shoe and said conductor lifting means is oriented to engage said conductor;
- operating said jack means to raise said conductor lifting means until said conductor lifting means engages with and lifts said conductor and said conductor shoe, whereby said conductor and conductor shoe are supported only by said jack means and not by said suspension insulator;
- detaching the suspension insulator from the conductor shoe and operating said jack means to lower said conductor lifting means for separating said insulator from said conductor and conductor shoe;
- pushing said slider toward the outer end of the board and away from said insulator a sufficient distance to allow the at least one lineman access to said suspension insulator without contacting the conductor or conductor shoe;
- attaching said suspension insulator to the helicopter, detaching the suspension insulator from said insulator support plate and removing the suspension insulator from said tower via the helicopter;
- delivering a replacement insulator via the helicopter to said tower, attaching said replacement insulator to said insulator support plate and detaching said replacement insulator from said helicopter;
- using a non-conductive stick,
- moving said slider along the board from the outer end of the board until the conductor lifting means, which is supporting the conductor and conductor shoe, is positioned directly underneath the lower end of the replacement insulator;
- operating said jack means to raise said conductor lifting means until the conductor shoe is aligned with the lower end of said replacement insulator;
- and
- attaching the conductor shoe to the lower end of said replacement insulator, operating said jack means to lower said conductor lifting means for separating it from said conductor and conductor shoe and moving said slider along said board away from said insulator and energized conductor.