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“BB” insulator

Electrical insulator for very high voltage transmission lines, dry arc of 190,000 Volts, 3 discs, model known as the BB No. 4390.

• Date: 1928-1934

• Place of manufacture: Folembray Glassworks (Aisne)

• Manufacturing technique: translucent green glass, press-and-mould process

• Dimensions: H : 39 ; Ø : 38 ; 25 kg

• Collection: Coll. association Folembray

• Credit: © Lucie Nicolas / Ecomusée de l’Avesnois


The insulating properties of glass were exploited in 1899 by Louis Guéroult, engineer and director of the Folembray Glassworks, the latter having made a name for itself with the famous Thévenotte bottle.
The glassworks prospered in the 1920s thanks to an insulator known as the BB. It was immortalized in a stained-glass window of Folembray Church. The window shows the director’s family and the glassworks’ employees offering a glass insulator to the Sacred Heart of Jesus!