Fa Union Made Overalls "A Smile of Satisfaction HEADLI with every pair." Will outwear two pairs of any printed stripe overall made. THE SECRET... The stripe is woven, not printed. This fabric is our own and can only be found in HEADLIGHT Overalls. Guaranteed the best Overall you ever bought or money back after thirty days' wear. Have you got yours yet? "A Smile of Satisfaction with every Pair" HEADLIGHT OVERALL (UNION MADE) Larned Carter & Co. Detroit Mich. World's Greatest Overall Makers Detroit. Port Huron, Mich., St Louis, Mo., Sarnia, Ont. PLATE 86-No. 3-E CONTROL VALVE, P-C PASSENGER Over Reduction Lap Position (Diagrammatic View) CAR BRAKE EQUIPMENT # ISOLATED PORTS AND CHAMBERS SERVICE RESERVOIR SERVICE CYLINDER ATMOSPHERIC & 1914 CAMBRIDGE, MAS PUBLISHED MONTHLY BY THE BROTHERHOOD OF LOCOMOTIVE FIREMEN AND ENGINEMEN COPYRIGHT, 1914, BY JOHN F. MCNAMEE Entered as Second-Class Matter January 21, 1914, at the Post Office at Columbus, Ohio, Plate 86-No. 3-E Control Valve, Plate 86 of the Westinghouse Air Brake Series of the Locomotive Firemen and Enginemen's Magazine Educational Charts shows the No. 3-E CONTROL VALVE of the P-C Passenger Car Brake Equipment in diagrammatic sectional appearance, with the operating parts in the positions they assume in the phase of Over Reduction Lap. This position is not directly the result of any air-braking operation on the part of the engineman nor of any variation of brake-pipe pressure, but is the sequence-the automatic termination-of that phase of Control Valve operation described with reference to last month's chart as the "over-reduction" position. AUGUST 1914 directly from chamber D was flowing to the reduction-limiting chamber; the release piston was in contact with-but not compressing-its graduating spring, and the port in the slide valve was uncovered by the graduating valve but with no effect further than that of sustaining the equalization of air pressures in chambers D, E and F; all other parts of the Control Valve were then in practically the same positions that we find them in the present plate of Over Reduction Lap. The brake-pipe pressure reduction has been carried beyond the point of full service application (heretofore described), to that in which the continued drop of brake-pipe pressure is without results that would affect the braking pressureproviding that the reduction is not carried below the point of equalization of the pressure chamber and reduction-limiting chamber: which is 60 pounds when In the description of the over-reduction carrying 110 pounds brake-pipe pressure, position in the previous number we left or 35 pounds if 70 pounds brake-pipe the Control Valve with the piston of the pressure is being carried. We will asequalizing feature at the extreme posi- sume in this case that the engineer's tion of its application stroke and its brake valve was lapped, checking the furgraduating spring fully compressed, its ther reduction of the brake-pipe pressure graduating-valve-port in the slide valve before it had gone beyond the point of open, through which pressure-chamber air equalization referred to-holding the Con trol Valve action within the stage of over reduction. We have followed the graduations of brake-pipe pressure to the point, now, Now there will be no further drop of considerably below the stage of full servthe brake-pipe pressure in chambers A ice application, and where no further reand B; and when the continuing feed of duction can be made without causing the air to the reduction-limiting chamber application of the emergency brake cylinfrom the pressure chamber and chambers der; which, if this should be done, and D and E had effected a slight reduction although having reached that state of acof the pressure in the latter combined tion by successive graduated reductions chambers, the pressure on the brake- of the brake-pipe pressure, the various pipe sides of the equalizing piston and parts of the Control Valve would assume release piston having thereby become exactly the same positions that they would slightly the greater, the pistons were if an intentional emergency application forced downward a short distance until were made directly from the position of stopped by contact with their main release and charging; therefore the reslide-valves, in the positions as shown in sults from continuing the brake-pipe rethe present chart; this back movement of duction below 60 pounds from 110 pounds the equalizing piston carried its graduat- (or below 35 pounds from 70 pounds) ing valve along, closing the port in the can be studied in the description of emerslide valve and cutting off any further gency position-the subject of a chart to flow of air from the pressure chamber to appear in a later number of the Magazine. the reduction-limiting chamber; air pressures on both sides of the equalizing piston now remain in equalization and hold the Control Valve from functioning any further, as long as the brake-pipe air is held at the same pressure. The back-lapse movement of the release piston also carried its graduating valve back, as shown in the plate, closing the port in the slide valve and thereby cutting off air communication between chamber E and chambers D and F; this, however, does not influence the Control Valve in any way while in this position. The application chamber and chamber C, after having equalized with the pressure chamber and having then been cut off from it, remains isolated, and the service brake-cylinder having received a corresponding pressure charge (as was explained in reference to the chart illustrating the service application position), the application portion assumed the lap position in which both the application valve and the exhaust valve were closed, and in which position it remains. A reduction, through leakage, of application-chamber pressure would cause an equal pressure discharge from the service brake-cylinder; such a possibility is provided against, however, as enough air from the service reservoir can feed past the ring in the small end of the servicereservoir charging valve to restore any ordinary leakage from the application chamber; but if such leakage should be greater than could be supplied past the packing ring, and if the brake should be held applied in Over Reduction Lap Position for a sufficient length of time, the service-reservoir charging valve will be lifted, making a directly open connection from the service reservoir with the application chamber. * All operative parts, air ports and chambers that are not brought into service in the position of Over Reduction Lap are omitted from the present chart, so as not to divert the attention of the student, and to avoid confusion of the many intermingling air passages. Air Brake Charts and Chart Racks. Realizing the necessity in air brake instruction work for the use of large charts lithographed in colors, such as the Westinghouse Air Brake Company has issued for years, for the purpose of illustrating the construction and operation of important parts of the air brake system, that company has given a great deal of attention not only to the details, color plan, and diagrammatic arrangement of the charts themselves, but also to the best method of mounting and handling these charts during lectures or demonstrations, and preserving them in good order when not in use, and as a result the Dust Proof Cylindrical Chart Rack, shown in Figs. 1, 2, 3 and 4, has been developed. Through the courtesy of the Westinghouse Air Brake Company we reproduce the cuts illustrating these chart racks and quote from their special publication No. 9017, as follows: tended for standard charts, 26 inches by "Cylindrical Chart Rack No. 1 is inRack No. 2 is intended for standard 33 inches in size, and Cylindrical Chart equipment charts 42 inches by 60 inches in size. No. 1 Chart Rack "The No. 1 Rack comprises simply a roller supported by two brackets which in turn are bolted to a hardwood baseboard suitable for attaching to the wall. At |