ENGINE No. 15. 



Simple Condensing Engine. 



Kind of engine Four valve (Corliss) 



Number of cylinders 2 



Diameter of each cylinder 23 in. 



Diameter of each piston rod 31 in. 



Stroke of each piston 5 ft. 



Clearance 3 % 



H. P. constant for 1 Ib. m. e. p. one revolution per min. .249 H.P. 



Inside diameter of steam pipe 6 in. 



Inside diameter of exhaust pipe 10 in. 



Condition of valves and pistons regarding leakage . . . Fairly tight 



Data and Results of Feed- Water Test. 



Character of steam Superheated 59 



Duration 5.C3 hrs. 



Weight of feed-water consumed 74,247 Ibs. 



Feed-water consumed per hour 13,187 Ibs. 



Pressure in steam pipe above atmosphere 77.6 Ibs. 



Vacuum in condenser 27.9 in. 



Mean effective pressure ... 40.49 Ibs. 



Revolutions per minute 61 



Indicated horse-power 615.1 I. H.P. 



Feed-water consumed per I. H. P. per hour 21.44 Ibs. 



Measurements Based on Sample Diagrams. 



CONDKN>I\<. 



CYLINDER. 



NON- 

 CONDENSING 

 CYLINDER. 



Initial pressure above atmosphere . . . Ibs. 



Cut-off pressure above zero Ibs. 



Release pressure above zero Ibs. 



Mean effective pressure Ibs. 



Back pressure at mid stroke, above or be- 

 low atmosphere Ibs. 



Proportion of stroke completed at cut-off . 

 Steam accounted for at cut-off .... Ibs. 

 Steam accounted for at release .... Ibs. 

 Proportion accounted for at cut-off . . 

 Proportion accounted for at release . . . 



76.7 

 80.4 

 20.3 

 45.33 



11.9 



.264 

 16.62 

 15.93 



)5 



.874 



73.2 

 80.1 

 23.6 

 36.05 



+ 2.6 



.298 

 22.41 

 22.29 



Engine No. 15 has a pair of cylinders provided with a jet- 

 condenser and direct connected air-pump. The exhaust piping 

 is arranged so as to run one cylinder condensing and the other 



82 



