262 DEVELOPMENTS IN OIL BURNING. 



the test boiler and its connections for water and steam tightness, the arrange- 

 ments for measuring water and oil and the apparatus for taking data. All 

 of these were found satisfactory, and the tests were proceeded with at once. 

 In all these tests oil was used as a fuel. 



"Civilian assistants from the office of the Inspector of Machinery, 

 Bayonne, N. J., were detailed for the purpose of taking data. Another set of 

 observers was furnished by The Babcock & Wilcox Company who took data 

 independently. The data taken by the two sets of observers were compared, 

 so that any errors in reading were corrected at once. " 



The report concludes as follows : — 



"The Board was particularly impressed with the excellent results 

 obtained with this boiler under the maximum rate of combustion, Test No. i , 

 which gives a combustion of 13.69 pounds of oil per cubic foot of furnace 

 volume. This is the equivalent of about 75.34 pounds of coal per square foot 

 of grate area in the same boiler when burning coal. The boiler in this test 

 steamed freely with a very slight increase in the wetness of steam, and the 

 falling ofif of efficiency was small for a rate of combustion much above 

 the maximum ordinarily used on boilers of the Navy under forced-draft 

 conditions. 



"After all the tests were completed the boiler was opened, cleaned and 

 thoroughly inspected for deterioration. No tubes showed any signs of dis- 

 tortion, and all tubes and headers were free of blisters. All baffles were in 

 good condition and properly placed. " 



It may be interesting to note that the wetness of steam referred to in the 

 Board's report did not exceed as a maximum 81 hundredths of i per cent, as 

 shown in the results of the tests which are given in Table IV. 



Oil and Coal in Combination. — The writer does not believe that two such 

 different fuels as coal and oil can be burned in the same furnace at the same 

 time with results in efficiency equal to those which can be obtained with 

 either fuel alone. The problem, always difficult, of securing complete com- 

 bustion of the volatile hydro-carbon becomes more difficult, and one fuel 

 inevitably interferes with the other. 



The injection of an oil spray over a coal fire is, however, a most effective 

 way of boosting up the capacity of the boiler and for this purpose the com- 

 bination has a wide field. 



As noted above, the United States battleships Wyoming and Arkansas 

 were to burn coal and oil in combination. Consequently after completing 

 the oil tests we turned our attention to the best method of getting the two 

 fuels to work together. Obviously the most satisfactory location for the 

 burners is between the fire doors. But owing to the fact that the ash pan. 



