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correct or change the adjustment, with this arrangement, it is necessary to first close the stop cock, then disconnect the pipe from the spring case, remove the cap nut, and turn the regulating nut in the governor top by guess; after which the cap nut is screwed on, the pipe reconnected, and the stop cock reopened; by consulting the red hand of the large duplex gauge, it can be ascertained how near to the desired figure the adjustment has been made; and usually the same procedure will have to be gone through several times before the adjustment is correct. On most roads this older style of excess-pressure governor top is being replaced by the newer style, explained in connection with the No. 6 equipment, but which is now the standard for both styles of the E-T equipment. If the stop cock in the feed-valve pipe branch to the older-style governor top should get accidentally closed (as it often does), not more than 45 pounds' pressure can be pumped up in the main reservoir while the automatic brake-valve handle is in Release, Running, or Holding Positions; but in the positions of Lap, Service, or Emergency Application, the mainreservoir pressure will be pumped up to the maximum figure. LEAKING OR BROKEN PIPES IN THE No. 5 EQUIPMENT.

With the exception of the two small, copper pipes known as the application-chamber pipe, and the doubleheading pipe, shown in colors in Fig. 48, the results from

No. 5 vs. No. 6 E-T Equipments

pipe leakage, or breakage, and the remedies therefor, are just the same in the No. 5 equipment as already explained in reference to the No. 6-equipment pipingwith one exception: If the BRAKE-PIPE BRANCH TO DISTRIBUTING VALVE in the No. 5 equipment becomes broken, it is usually impossible to go right on after simply plugging the ruptured pipe, without the locomotive brake sticking-brake shoes rubbing the wheels, and a distressing blow of air from the main exhaust port of the automatic brake-valve; and at the first light application by either the automatic or independent brake-valve, the application-chamber pressure will run clear up to 53 pounds and “pop" at the safety valve. To avoid this trouble, when the brake-pipe branch gets broken, close the cut-out cock in the main-reservoir supply pipe to distributing valve, and proceed (after plugging the broken pipe), without the use of the locomotive brake in any kind of application whatever.

If the APPLICATION-CHAMBER PIPE (orange-colored, see Fig. 48) starts leaking at any point between the distributing valve and the independent brake-valve, the locomotive brake will not hold probably not set at all—as the result of any brake-pipe pressure reduction; if the leak is not too bad, an application by the independent brake-valve will cause the locomotive brake to hold as long as it remains in the Quick-Appliation Position, but the brake will release as soon as

the brake valve is lapped. Leakage only from the section of this pipe connecting the independent and automatic brake-valves will have no effect whatever upon an application by the independent brake-valve, but the locomotive brake will not apply from any reduction of brake-pipe pressure, unless the independent brake-valve handle be placed in Lap Position before the automatic application is made. If either section of this pipe is broken off, the effect will be the same as severe leakage.

Find the point of leakage from tests as suggested above. The temporary, road remedies are: If the distributing-valve section of this pipe is ruptured (be sure in cases of leakage from these small, copper pipes that it is not simply due to loose pipe-union nuts that can be quickly tightened, and the leakage stopped), plug the pipe toward the distributing valve, and disconnect a union in the double-heading pipe-preferably at a point in the cab; you will then have no use whatever of the independent brake-valve, but the locomotive brake will apply as usual from service or emergency reductions of brake-pipe pressure; the holding effect on the locomotive brake in Release and Holding Positions of the automatic brake-valve is lost, however, and this should be borne in mind when making all applications while running. If the automatic brake-valve section of this pipe is leaking or broken, keep going on: and,

Broken Pipes, No. 5 Equipment

if you can't stop the leak, just before making an automatic application place the independent brake-valve handle in Lap Position, and the locomotive brake will operate, and hold, as usual; when the automatic brakevalve handle has been returned to Running Position (and not before), return the handle of the independent brake-valve to Running Position, and the locomotive brake will release.

If the DOUBLE-HEADING PIPE (blue-colored, see Fig. 48) develops a leak, or breaks between the distributing valve and double-heading cock, the only effect is that it will be noticed that the locomotive brake will release in the Release and Holding Positions of the automatic brake-valve; all that is necessary to do in this case—if it is the leading engine, from which the train brakes are operated-is to plug the pipe toward the distributing valve, and no difference from normal brake operation will be experienced. With this section of pipe broken on one of the “cut-outengines in double- or tripleheading, just pay no attention to it, for at this time that pipe has an atmospheric terminus anyhow; the only difference is that this engineer could not retain his locomotive brake in case of a train-brake release while running, made from the leading engine, except by placing his independent brake-valve in Quick Application Position. If the section of this pipe between the double-heading

cock and automatic brake-valve is broken or leaking, it will have absolutely no effect on the engine from which the train braking is being done; but on all “cut-outengines that may be in the train the result will be just the same as already explained in reference to the main section of this pipe connecting with the distributing valve.

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