electrical insulating materials. PTFE insulation. Scheme, description

ENCYCLOPEDIA OF RADIO ELECTRONICS AND ELECTRICAL ENGINEERING
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electrical insulating materials. PTFE insulation. Encyclopedia of radio electronics and electrical engineering

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Encyclopedia of radio electronics and electrical engineering / Electrical materials

PTFE insulation (polytetrafluoroethylene), abbreviated F-4, has high mechanical and dielectric properties. It is used in the temperature range from -90 °С to +250 °С. Along with F-4 copolymers F-4D, F-4M, F-40Sh are used.

F-4 is exceptionally resistant to most chemicals.

The thickness of the wire insulation is taken equal to 0,25 mm at voltages up to 600 V and 0,4 mm at voltages up to 1000 V. The insulation on the cores is applied either as a continuous monolithic layer of F-4D, F-4M, F-40Sh, or by winding with tape insulation from F-4, which is then subjected to heating to obtain solidity.

Author: Koryakin-Chernyak S.L.

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