Strain Insulator

Strain Insulator.

With the rapid development of heavy electric railway work there has arisen a demand for efficient strain insulators for catenary work, where the link-type insulators are unapplicable. The existing types of strain insulators, when built for heavy strains and high voltages, become very large, heavy and expensive and some forms lack sufficient reliability. The accompanying illustration shows a new type of strain insulator, patented by J. P. Nikonow, to meet the occasion. In this insulator a mica tube is inserted between conical metal parts of comparatively small size, insuring light weight of the piece. In order to reduce the stress on the mica tubing several metal sheets are interposed between the mica and metal parts. The mica insulation is allowed to extend considerably beyond the metal parts, so as to reduce creeping leakage to a minimum. A sheet-metal cap covers the top of the insulator, protecting it from the atmospheric influence, and with the same purpose a removable porcelain bushing is fitted over the insulator. The patent rights of this insulator have been acquired by the Westinghouse Electric & Manufacturing Company.

Strain Insulator.