232 



TRIPLE VALVES 



provided for that purpose, and these parts put back into place. 

 See that the graduating spring and sleeve work properly, and 

 that all gaskets are in good condition; a defective gasket 

 should be replaced with a new one. Examine and clean the 

 by -pass valve and piston of the type L triple valve and replace 

 without oiling. If the rubber seat of either the emergency 

 valve or the by-pass valve is defective, a new one should be 

 substituted. The safety valve of the type L triple valve 

 should also be taken apart and cleaned, and reassembled 

 without oiling. The safety-valve and brake-pipe strainers 

 should be thoroughly cleaned. After the triple valve has been 

 cleaned and put together, it should be tested on the triple- valve 

 test rack. 



TRIPLE-VALVE EQUIPMENT 



In the accompanying table the approximate light weights for 

 cylinder sizes specified are calculated for 50-lb. cylinder pres- 

 sure for all types of equipment plain and quick-action triple 

 valves, and ET engine and tender equipments and for a total 

 leverage not to exceed 9 to 1. 



FIG. 1 



Comparative speed-time-retardation curves for an eight-car 

 train, when emergency applications are made, are shown in 



