06930254 is referenced by 1 patents and cites 9 patents.

A composite insulator containing means for providing early warning of impending failure due to stress corrosion cracking, flashunder, or destruction of the rod by discharge activity conditions is described. A composite insulator comprising a fiberglass rod surrounded by a polymer housing and fitted with metal end fittings on either end of the rod is doped with a dye-based chemical dopant. The dopant is located around the vicinity of the outer surface of the fiberglass rod. The dopant is formulated to possess migration and diffusion characteristics correlating to those of water, and to be inert in dry conditions and compatible with the insulator components. The dopant is placed within the insulator such that upon the penetration of moisture through the housing to the rod through a permeation pathway in the outer surface of the insulator, the dopant will become activated and will leach out of the same permeation pathway. The activated dopant then creates a deposit or stain on the outer surface of the insulator housing. The dopant comprises a dye that is sensitive to radiation at one or more specific wavelengths or is visually identifiable. Deposits of activated dopant on the outer surface of the insulator can be detected upon imaging of the outer surface of the insulator by appropriate imaging instruments or the naked eye.

Title
Chemically-doped composite insulator for early detection of potential failures due to exposure of the fiberglass rod
Application Number
10/641511
Publication Number
6930254 (B2)
Application Date
August 14, 2003
Publication Date
August 16, 2005
Inventor
Stephen J Hudak Jr
Helotes
TX, US
Joseph N Mitchell
San Antonio
TX, US
Mary C Marshall
San Antonio
TX, US
Ralph H Hill Jr
San Antonio
TX, US
Andrew J Philips
Charlotte
NC, US
Agent
Dergosits & Noah
Geoffrey T Staniford
Assignee
Electric Power Research Institute
CA, US
IPC
H01B 017/34
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