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Glass Bushings & Wall Tubes

Glass bushings were most commonly used on load balancing capacitors.  These were typically in amber or clear glass and were mounted directly to the metal capacitor case.  In the timeframe these were made, PCB's (Poly- Chlorinated Biphenyls) were present in the fluid within the capacitors, so care should be taken if a complete unit is found.  There are also glass wall tubes and bushings for other purposes.  The CD 312 that has been discussed as being a base for a CD 249 No. 0 Provo is most likely a bushing or wall tube.  A wall tube was designed to insulate a high voltage wire as it passed through a wall - the wire would typically go through the center of the insulator.

Shown is a General Electric capacitor with amber glass bushings.  Two bushings with metal removed are also shown.  Picture courtesy Dwayne Anthony


Shown are two capacitor bushings in different shades of amber.  These are about 6 inches tall and have had the metal removed.

Here are two capacitor bushings with metal still attached.

Shown are seven small glass bushings.  These have never been used and their purpose not known -- they are designed with a soldered band to allow them to be soldered to metal.  These are 1 and 2 inches tall respectively.



Here is a glass wall tube - although unmarked., this style was cataloged by Hemingray.

This large bushing was used to insulate a large electrical switch panel.



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