[Trade Journal]
Publication: Railway Signaling and Communications
Chicago , IL, United States
vol. 42, no. 9, p. 592-593, col. 3,1
STONE-PROOF INSULATOR
The Communication Equipment & Engineering Company, 5646 West Race Street, Chicago 44, has announced a new insulator which is said to be superior to glass and porcelain, 60 per cent lighter, chip proof, and will not break or split when carried on trucks or dropped. Known as the Clevelon Type CC-42 insulator, it is made of an insulating material which will withstand repeated blows from stones, shot-gun pellets and bullets.
Absorption tests have shown that there is no appreciable change in the thickness or appearance of the material after 48-hr. immersions in thin oil, twice-normal sulphuric acid and calcium sulphate solutions. After being immersed in water for approximately six weeks, samples dried in air for about 10 min. have showed no measurable decrease in resistivity. Dielectric strength on a sample .127 in. thick has showed a strength of 123 volts per mil, or a total breakdown voltage of 15,500 volts. Leakage resistance of the Type CC-42 insulator measures over 500 megohms under dry conditions, the dry flash-over voltage being over 40 kv.
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| Stone-Proof Insulator |
Field tests over a period of approximately two years indicate that the material has no appreciable deterioration under adverse weather conditions, such as occasioned by the presence of corrosive atmosphere caused by sulphur smoke and fumes. Insulators installed on telephone and signal lines, where stones are thrown at the wires, indicate that the material withstands repeated blows without loss of insulating properties.
