TRIPLE VALVES 197 



the LN passenger equipment was designed and perfected. 

 The LN equipment proved satisfactory for cars up to 130,000 

 lb., but the construction of cars of over 150,000 Ib. made the 

 development of the PC passenger equipment necessary. 



P-l (F-27), QUICK-ACTION, PASSENGER, TRIPLE 

 VALVE 



The P-l (F-27), quick-action, passenger, triple valve, shown 

 in Fig. 1, is used with the 8-in. and 10-in. passenger-car 

 brake cylinders and the 10-in. passenger -tender brake cylinders; 

 its weight is 38 lb. Though similar in appearance, this valve 

 differs essentially from the H-l and H-2 freight triple valves, 

 and should never be used in connection with freight-car brakes. 

 In addition to being marked P-l on the valve body, it may 

 also be distinguished from the freight triple valves by the 

 fact that it has one exhaust outlet while the freight triple 

 valves have two; it may be distinguished from the P-2 triple 

 valve in having two instead of three bolt holes in the back 

 flange. The bore of the P-l slide-valve bush is If in. The 

 operation of this triple valve is the same as the type H triple. 

 The piece number of the P-l triple valve, complete, is 1,760; 

 the piece and reference numbers of the various parts are given 

 in the accompanying list. 



PC. No. Ref. No. Name of Part 



1,761 2 Body, bushed. 



29.138 3 Slide valve. 



1,767 4 Main piston, includes 5. 



10,032 5 Main-piston ring. 



1,730 6 Slide-valve spring. 



29.139 7 Graduating valve. 



9,752 8 Emergency piston, includes 30. 



1,740 9 Emergency-valve seat. 



1,735 10 Emergency valve, includes 11 and 28. 



1,737 11 Rubber seat. 



1.745 12 Check- valve spring. 



12,850 13 Check-valve case, complete, includes i-in. 



pipe plug. 



1,754 14 Check- valve-case gasket. 



1,744 15 Check- valve. 



1,751 16 Strainer. 



1.749 17 1-in. union nut. 



1.750 18 1-in. union swivel. 



1.746 19 Cylinder cap. 



1.747 20 Graduating-stcm nut. 



