WHAT HAS "CRAZING" TO DO WITH
ARC RESISTANCE?
Power arcs as severe as 3,800 amperes for one second
have been held against PYREX brand insulators by use
of arc shields. The glass does not fail dielectrically.
The surface is "crazed" -- covered with fine, hair-like
cracks, no more than 1/16" deep, in those
places where the glass has melted, locally, from the heat
of the arc, and again solidified in cooling. The insulators
are substantially unimpaired and can go back into service
immediately. Other materials shatter badly under less
severe conditions.
WHY CAN CORNING OFFER THE NEW 9"
SUSPENSION INSULATOR?
|
This new unit is revolutionary. Just 9" in
diameter, weighing only 6½ lbs., it meets
and exceeds all requirements for a standard
15,000 lb. insulator. The high mechanical
strength of tempered glass and the tremendous
dielectric strength of PYREX brand electrical
resistant glass glass makes it possible to
decrease the diameter of the skirt correspondingly.
This is done without sacrificing dry or wet
flashover values, leakage distance, or other
essential characteristics. This inexpensive,
sturdy, lightweight insulator is possible only
in tempered PYREX brand glass.
What a team! The 9" for standard duty. The
10" for super-duty!
* * *
. . . If space permitted, many other questions
concerning insulator design and performance
could be discussed. For example, "What happens
when a suspension insulator is tapped, hard
and square on the pin, and then tested electrically?"
Try it -- with glass, and other materials! Or,
what about oil puncture tests and thermocycle
strength? If you are interested in these or
other insulator problems, remember it is always
"open house" in Corning and our facilities are
at your disposal. Or, write . . .
|
