Sister Unit of Failed Bushing
This shows the areas sampled using Scotchbrand Frosted
"Magic" tape. Tapelifts preserved the particle distribution
qualitatively and quantitatively and allows for a detailed particle and chemical
analysis of the materials on the surface of the bushing.
Macrophotograph
Definition/Function:
The particles on the surface of this bushing showed high concentration of weld debris
along with nitrates and gypsum. The nitrates deliquesced
at 48% relative humidity. This is consistent with ammonium nitrate, a fertilizer and an
areosol common near heavily traveled roads. The
flashover occured in the morning and was the result of the combination of the weld
residue and the electrolyte. Bushings away from the welding
activity were not failing.
Significance in the Environment:
Characteristic Features:
Associated Particles:
References:
