DETAIL OF DERRICK CONSTRUCTION.
Inasmuch as fuel economy is of little importance, since either waste gas or oil can be used, a large drop in the distributing system is permissible, and a radius of three or four miles from the power-house can be economically attained by the use of 210 to 250 volt lamps on the three-wire direct-current system. At present the maximum distance is 255 miles, and four voltages of lamps are employed. The derricks are wired on the two-wire system with No. 14 T. B. W. P. medium, hard-drawn wire, care being taken to keep all wires on the outside of derrick house wherever possible. Although the wires and insulators have been in some cases completely sprayed and saturated with oil from the gushers, no troubles of insulation have been experienced.
At the time this work was started, there was a small plant on the Pinal Oil Company’s property near by, where keyed sockets were used until one of the drillers was injured by a gas explosion caused by turning off one of the lights. This, of course, suggested the care necessary to guard against such accidents. In the present installation, double-pole fuses were constructed for each derrick and tank house, by using two weatherproof sockets and Edison plug fuses, all inclosed in a gauze cylinder like a Davy mine lamp. Switches for tank house and derricks were also inclosed in gauze. In wiring the derricks, sleeves were used for splicing, so that in the whole system no solder nor torch was used. Specially designed heavy wire lamp guards and portables, with wires inclosed in cotton-covered garden hose, are other features of the derrick wiring. When drilling is commenced, the derrick is wired for eleven lights. Tank houses, some fifteen or twenty in number, are wired with a light over each tank.
POWER-HOUSE.
The power-house is of only passing interest, being designed for reliability and minimum first cost, and with the idea of transplanting it to some new location should future conditions dictate. The view shows two 10×10 Shepherd engines, clutched to either end of a shaft, from which two 45-kilowatt, 250-volt, direct-current Westinghouse generators are belted. In case of accident to one generator, a switch on the switchboard converts the 3-wire to a 2-wire system, using the two outside wires as one, and the neutral as the return conductor. Three 48×14 fire-tube boilers supply steam at 125 pounds pressure. The power-house is in a perennially cool location on a hill crest, so that it could be made small and cozy.
The system has been in uninterrupted and satisfactory operation for two years. The only trouble during the time was caused by one wire of one span breaking, due to an imperfection in splicing. The section has long-continued and severe winds, much rain and cold weather, but two winters have developed no imperfections. Although the lights burn all night, no interruption has been experienced. Reliability is important, since, if the lights failed, there would be a temptation to light candles or lanterns at a critical time.
The system was designed and supervised by Mr. Copeland, of Messrs. Clem. Copeland and F. R. Schanck, consulting engineers for the Union Oil Company. Mr. C. W. Crawley, who is at present electrical superintendent, was foreman of construction.