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part, when leaking), unless the locomotive is placed in a train of which the brakes are operated from another engine; hence the name of the latter pipe, as given in the Color Key—the “Double-Heading Pipe."
The orange-colored Application-Chamber Pipe therefore becomes a most important part of this equipment; the application chamber and application cylinder are in permanent communication with each other in the No. 5 distributing valve, and from those combined chambers the application-chamber pipe leads to the atmosphere, via the independent brake-valve, at the automatic brake-valve—when both brake-valves are in Running Position; through this pipe the locomotive brake is released when the automatic brake-valve is returned to Running Position after an application, and applied or released by the independent brake-valve. It will be observed that when the automatic and independent brake-valves are placed in Release Position, pressure that may have been contained in the application chamber and application cylinder will be exhausted, and the locomotive brake released regardless of whether the equalizing, or triple-valve, portion of the distributing valve is in release position or not; and from this it follows that when an automatic application is made from the train-by use of the conductor's valve, an angle cock, or from the train parting—there is a special reason for placing the automatic brake-valve handle
Piping, No. 5 Equipment in the Lap Position, for otherwise the locomotive brake will not hold; if this duty should be delayed, and the brake-valve handle later be placed in the Lap Position, the locomotive braking pressure will be built up, however, by the maintaining pressure which in this style of equipment originates in, and is supplied by, the distributing valve.
The blue-colored or Double-Heading Pipe leads from the exhaust port of the equalizing, or triple-valve (lower), portion of the distributing valve to the doubleheading cock under the automatic brake-valve, and under ordinary conditions is blanked by the latter. The double-heading cock has two ports through it, the ports in the cock key being at right angles to each other; when the cock is "open,” brake-pipe pressure flows through it, and the port connecting with the double-heading pipe is closed; when, as on the second engine in double-heading, the double-heading cock is “closed,” while it does cut off connection between the automatic brake-valve and the brake pipe, the smaller port in the cock key is then open, connecting the section of the blue pipe that comes from the distributing valve with the upper section of that pipe-line leading to the automatic brake-valve; but here the pipe is again blanked, until the brake-valve handle is placed in Lap Position, in which, through a port in the rotary valve, the double-heading pipe line finds an exit to the
atmosphere at the large, emergency-exhaust opening. Outside of the two colored pipes, as noted, the whole No. 5 equipment is about the same as the No. 6.
In the distributing valve, the upper, or application, portion is exactly the same; and the lower, or equalizing, portion only differs in a slight variation of the ports in the equalizing slide valve, and the absence of the graduating spring that is supplied in the No. 6 distributing valve. The safety valve on the No. 5 distributing valve is set at 53 pounds, instead of 68 pounds as in the No. 6 equipment. The small air gauge is of the single-pointer style, the one (black) hand registering locomotive brake-cylinder pressure. Refer to the “No. 5 Distributing Valve,” the “H-5 Automatic BrakeValve,” the “No. 5,” or “S-F,” “Independent BrakeValve,” the “B-4 Feed Valve," the “B-3 Reducing Valve," and the “S-F4 Pump Governor," in this style of equipment.
HANDLE POSITIONS OF THE ENGINEER'S BRAKE-VALVES,
No. 5 E-T EQUIPMENT. The AUTOMATIC and INDEPENDENT BRAKE-VALVES have the same number of operating positions, each, in the No. 5 as in the No. 6 equipment, and their action is so nearly the same that if an engineer was used to either style, he could operate the other without any special instructions, in ordinary service; but there is
The No. 5 Brake Valves
some difference in the work performed by the several parts of the equipment, which will be briefly mentioned. It will be assumed that an automatic application had been made:
THE H-5 AUTOMATIC BRAKE-VALVE. In Release Position of the handle, the results obtained are precisely the same as explained in reference to the H-6 valve; main-reservoir pressure is supplied directly to the brake pipe, releasing the train brakes and moving the equalizing portion of the distributing valve to release position, which, in addition to permitting the recharge of the pressure chamber, connects the application-chamber pressure with the blanked doubleheading pipe. Application-chamber air fills the application-chamber pipe from the distributing valve, through the rotary of the independent brake-valve, to the automatic brake-valve, where it is blanked by the rotary valve. Main-reservoir pressure is being supplied from the automatic brake-valve to the chamber under the diaphragm of the excess-pressure governor top, controlling the pump at the minimum m.-r. pressure. Air to the warning port is from main-reservoir pressure direct.
In Running Position the direct supply of mainreservoir pressure to the brake pipe is cut off, and the latter receives its pressure from the 70-pound feedvalve pipe, as usual in the E-T equipment. A port in
the rotary valve now opens the terminus of the application-chamber pipe to the atmosphere, and the locomotive brake releases (the only position of the brakevalve in which it does discharge that pressure). The excess-pressure governor top still receives main-reservoir pressure from the brake valve.
In the Holding Position, feed-valve pressure supply to brake pipe is continued, but the application-chamber pipe is again blanked; and if the brake-valve handle had been drawn quickly to this position from that of Release, the effect would be the same as in Running Position, except that the locomotive brake would remain applied. After using this position as long as may be necessary, release the locomotive brake by returning the brake-valve handle to Running Position, and leave it there. Pump control is the same as in Running Position.
Lap Position. In the three first positions of the brake-valve, just mentioned, chamber D and its connected equalizing reservoir received the same pressure that was supplied to the brake pipe; but in Lap, Service, and Emergency Positions, chamber D is cut off from the air supply. Also, in Lap Position the feedvalve pressure no longer flows to the brake pipe, and all separable communications in the rotary valve and seat are blanked-except one connection that is made in this position, only: —the terminus of the double