ENGINE No. SO. 



Simple Condensing Engine. 



Kind of engine ... Four valve 



Number of cylinders 2 



Diameter of cylinder 16 ins. 



Diameter of piston rod 21 ins. 



Stroke of piston 3 ft. 



Clearance 5 % 



H. P. constant for one Ib. m. e. p. one rev. per min., each .0361 H.P. 



Inside diameter of steam pipe 5 ins. 



Inside diameter of exhaust pipe 6 ins. 



Condition of valves arid pistons regarding leakage . . Some leakage 



Data and Results of Feed-Water Test. 



Character of steam Ordinary 



Duration 5. hrs. 



Weight of feed-water consumed 22,055 Ibs. 



Feed-water consumed per hour 4,411 Ibs. 



Pressure in steam pipe above atmosphere .' 83.4 Ibs. 



Vacuum in condenser 26.7 ins. 



Mean effective pressure . . . . 31.27 Ibs. 



Revolutions per minute 90.4 



Indicated horse-power 205.9 I. H.P. 



Feed- water consumed per I. H. P. per hour 21.42 Ibs. 



Measurements based on Sample Diagrams. 



Initial pressure above atmosphere 74.4 Ibc. 



Cut-off pressure above zero 75.0 Ibs. 



Release pressure above zero 14.9 Ibs. 



Mean effective pressure ; 31.16 Ibs. 



Back pressure at mid stroke below atmosphere 11.15 Ibs. 



Proportion of stroke completed at cut-off . 139 



Steam accounted for at "cut-off 13.81 Ibs. 



Steam accounted for at release 16.45 Ibs. 



Proportion of feed-water accounted for at cut-off .645 



Proportion of feed-water accounted for at release .760 



Engine No. 30 has a pair of cylinders each having two steam 

 valves and two exhaust valves, all being slide valves. The 

 condenser is of the jet type operated by an independent air-pump 

 driven by steam taken from the engine-pipe. The quantity of 

 steam used by the condenser was determined by an independent 

 test and allowed for. Steam is furnished by vertical water 

 tube boilers, and a separator is fitted to the main steam pipe. 



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