Dirigo insulators made by Ohio Brass

[Trade Journal]

Publication: Street Railway Journal

New York, NY, United States
vol. 16, no. 16, p. 863, col. 2

"DIRIGO" is the distinguishing name given by the Ohio Brass Company, Mansfield, Ohio, U. S. A., to the insulating material which they employ in the manufacture of their overhead electric railway materials. It was first made commercially seven years ago, and much of the original output produced in the first few months of its manufacture is now in use; a service which, both long and severe, has done much to establish its present reputation. The ingredients, which are prepared from a formula adopted after much experiment, as well as the methods of handling them, in the course of making the completed insulation, have been so carefully guarded that although many attempts have been made to duplicate the Dirigo none has been as yet successful. In appearance the insulation is a dark green, and the word "Dirigo"' appears in raised letters on the surface of each piece, thus plainly distinguishing it. The characteristics, which are those qualities pre-eminently required for the use to which it is put, are toughness, elasticity, non-conductivity of heat or electricity, imperviousness to moisture, and, most important of all, great durability when exposed to the elements. It has been tested in nearly every climate of the world, and is alike unaffected by the intense cold of Canada or the high temperatures of the tropics, the dryness of high altitudes or the fogs and dampness of the seashore. It was perfected, especially, as an insulating material for overhead trolley systems, and in that capacity fills every requirement, but is equally fitted for other purposes where a good insulator is necessary, such as for controllers, motors and dynamos. As yet, however, this is an undeveloped field, for the Ohio Brass Company, although its plant has been operated both day and night almost steadily, has not been able to fill orders promptly for its regular line of railway materials during the past year. The testing of the finished product plays a most important part in its handling, and is carefully and accurately conducted. All articles are given an electrical test ranging from 5000 volts to 10,000 volts, depending upon the use they will be put to, and those whose shape and size will permit are subjected to a mechanical test. For the high voltage a special alternating-current transformer, with the aid of a water rheostat, gives a graduated pressure from zero to 10,000 volts; the readings being taken from a voltmeter connected in the circuit. A Reihle Brothers' machine is used for making the mechanical tests, and, if the device will stand as much, pressures up to 10,000 lbs. can be obtained. The severity of the tests and the care with which they are made is largely accountable for the high standard of excellence of Dirigo insulation and those articles in the construction of which it enters.


Keywords:Dirigo : Ohio Brass Company
Researcher notes: 
Supplemental information: 
Researcher:Elton Gish
Date completed:August 9, 2010 by: Elton Gish;