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PRESSURES

EXHAUST STEAM

ATMOSPHERIC

MAIN RESERVOIR

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PIPE FROM
BOILER

AIR INLET

Locomotive Firemen's Magazine Educational Charts.

WESTINGHOUSE AIR BRAKE SERIES.

PLATE IV-NINE AND ONE-HALF INCH PUMP (Back View.)

Copyright 1903, by W. S. Carter.

Entered December 4, 1902, at Indianapolis, Ind., as Second-class Matter, under act of Congress of March 3, 1879.

BROTHERHOOD OF

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Plate IV-Nine-and-One-half-Inch sage F, thence upward through passage Pump (Back View). and out under the valve 86, into passage

m, thence into the upper end of the cylinLATE IV of der, as shown above piston 66. It will be

PSeries of the Locomotive Fire noted that atmospheric pressure also ex

men's Magazine Educational Charts is a sectional and perspective view of the back of a 92-inch air pump. The pistons have traveled about three-fourths of their downward stroke.

tends downward through passage F and into passage n, under lower intake valve 86. A portion of passage F has been removed in order to show passage 0. It will also be noted that atmospheric pressure is shown in passage r, r', under the upper discharge valve 86.

The steam from boiler enters at X, passing upward through passage a and entering chamber A at a2. The upper portion of passage a and port a' is not shown here, having been removed in order to show the differential valve, slide valve 83, and ports c', d, and b in detail.

When the differential valve is in the position shown, steam from chamber A passes down into the upper end of the steam cylinder through port c1 and passage c. The point of entrance of this passage into the cylinder is not shown here, as it lies beyond exhaust passage d'. The steam is shown, however, in the upper end of the steam cylinder, above piston 65.

The unique feature of this drawing is the graphic manner in which the passage of exhaust steam from the lower end of the steam cylinder is shown. The steam in exhausting from the lower end of the steam cylinder passes out through ports b2 and upward, beyond passage a, through b' and b into the cavity under the slide valve 83, thence downward through d, d1 and d, out through exhaust pipe at Y.

The air piston in passing downward creates a partial vacuum in the upper end of the air cylinder, causing the air to enter through the intake W into the pas

The downward stroke of piston 66 has compressed the air in the lower end of the cylinder, which is passing out into passage p' through ports p. The pressure has lifted the lower discharge valve 86 from its seat and the compressed air is passing upward into passage G and out through the discharge pipe at Z, into the main reservoir. It will be noted that the compressed air also passes into passage O and presses the lower intake valve 86 down on its seat. It will also be noticed that the compressed air fills the upper portion of passage G, and presses upper discharge valve 86 down on its seat. A part of passage G has been removed in order to show passage r1 and ports r.

Rules Meant to be Violated.

It complicates matters when railway officials promulgate rules by which employes are to be guided, except that under certain conditions the rules are to be violated. Some years ago bulletins were posted by many officials forbidding the use of the air brake in emergency position when no emergency demanded it. What constituted an "emergency" was

not defined in the bulletin. Flat spots on drivers continued to show up. Soft metal plugs were then inserted in the side of the brake valve, and more bulletins posted, which informed the engineers that

thing he refused to use his emergency, and thereby break the plug, until he knew he was going to hit. Then to excuse himself for using the emergency he had a broken pilot to show.

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THE BOILER ROOM OF THE SWIFT PLANT AFTER THE EXPLOSION

Some years ago, when the practice of placing brakes on drivers was instituted, some motive power officials issued bulletins forbidding the running of locomotives with the driver brakes cut in, because their use caused flat spots. An ex

ception to the rule was when the engineer believed that the driver brakes were essential to safety. Regardless of the excuses of the engineer, or what he said he "believed," a flat spot called for a reprimand or suspension, and the official cited the bulletin forbidding the running of locomotives with driver brakes cut in.

Where double-headers are now run, rules are in force which make it obligatory for the man on the second engine to keep his brake valve cut out, the man on the head engine doing the braking. The only exception to the rule is when the first engineer calls upon the second engineer to use his brake valve. Where accidents have occurred because of a fail ure of the first engineer to stop the train the blame is also thrown upon the second engineer, because he did not violate the rule, and cut in his brake valve.

Recently the following incident OCcurred on a well-known western road: A double-header train was descending a long grade on which they had an order to slow up for a passing track, as there was a disabled engine on the main line. The head man was in charge of the brakes and the second man was following the established rule of keeping his brake valve cut out. After passing the mile board the second man saw that the train was not being slowed down as it should be, called to the head man with his whistle to apply his brakes, and then called to the train crew to apply brakes. The stop

was made too late and an accident occurred. The second engineer was discharged for not cutting in his brake valve. The information at hand leads to the belief that the head man had already fully applied his brake, thereby exhausting all of the air from the train line.

This peculiar case was referred to three air-brake experts, who had no information as to where the accident happened, and the following answers were received from two of them:

valve was in the "running" or "release" positions, without being notified by the leading engineer to do so, I would discharge him, if I had authority to do so. The action has a releasing effect-or it may prevent the other engineer being able to apply the brakes. It is a dangerous action.

"In case of danger, it is understood by all practical railroad men, that if the train must be stopped immediately, any train or engineman is free to, and expected to, use any means whatever to stop it, and if that means to get the air brakes applied he must get the air out of the train pipe by the quickest way, therefore:

Expert No. 1.-"A standard set of rules to be observed in double-heading has not yet been adopted generally, and only a few roads have equipped their engines for double-heading safely, but they continue to do it just the same. The one rule that is generally enforced is that the leading engineer shall 'cut in' and operate the air brakes; the second engineer to cut his brake valve out from any connection, whatever, with the train line before leaving the original terminal-thenceforth not to cut in again. And if I could prove that an engineer, while running over the road with the second engine, double-heading, had cut his brake valve in to connection with the main train line while his

"If the second engineer is properly cut out and becomes aware of danger that requires the train to be stopped, and the leading engineer does not see the danger, and the second engineer can not get the leading engineer to understand or observe his signal to stop, it is the duty of the second engineer to throw his brake valve into emergency and then open his cut-out cock to the train line and leave it open until train is stopped.

"It would be my ruling, on this road, that in a case as described in the attached letter, the second engineer had done all that he is required to do, when he felt the brakes being applied from the head engine. Responsibility thenceforth rested upon the leading engineer.

"If the second engineer was certain that the leading engineer had applied the brakes with full force, there was nothing further that he could have done. He could not, however, be positive as to that, as his gauge was also cut out from the main train line and he could only guess from the way the brakes were holding as to whether they were full-on or not. If he judged they were not-it hinges on his own statement-he should have completed the application as before described. But I could not hold that the second man was in any sense at all negligent in the matter."

Expert No. 2.-"Although this communication does not state specifically that speed of the train down the grade with the leading engineer was controlling the the air brake, yet I reason that he was; else, as stated further on in the statement, the second engineer would not call to him for brakes first, and afterward call to the train crew for brakes, when he could just as well call to them for brakes at first had they been in control with the hand brakes.

"Assuming, therefore, that the leading engineer was controlling the speed of the train down the grade with the air brake, the second, or following, engineer should not interfere by cutting in his brake valve unless there was danger of accident, or, in other words, an emergency which required the train to be stopped, when he should, by all means, cut in his brake valve, placing the brake valve handle at emergency position. By so doing, the second engineer has the condition of affairs revealed to him at once; that is, he can

tell instantly whether there is any air in the train pipe or not. If, upon cutting in the brake valve on the second engine and placing the valve in emergency position, no air blows out at the brake valve, the engineer then knows that the train pipe pressure has been exhausted and if the brakes are not then holding as they should, resort must then be had to the hand brakes, the reverse lever and sand to effect a stop. Whether all or a part of these stopping devices are to be used depends upon how urgent is the necessity for the stop.

"In case of double-heading, cutting in the brake valve on the second engine will have an effect upon the operation of the

brakes depending upon conditions as follows: First, if brakes are all released and train pipe is charged to standard pressure, cutting in the brake valve on the second engine with handle in running position or full release would prevent the leading engineer from applying the brakes in the service application, but not in emergency; second, if the leading engineer has the brakes applied either with a full or a partial application, and the second engineer cuts in his brake valve while the brakes are so applied, leaving the handle of his valve in either the running or full release position, the effect of cutting in the valve would be to release the brakes. If before cutting in his brake valve, he moved the brake valve handle to the serv

while if they were already fully applied, cutting in the brake valve on the second engine and placing the handle of the valve in emergency or service position would not affect the brakes in any way.

"Under the conditions cited in the communication, in my judgment, the man on the second engine, after passing the mile board, then calling for brakes to the leading engineer and not getting them, should have cut in his brake valve and assumed control of the brakes himself, and should not have called to the train crew to stop the train until after he had done this, unless there was urgent necessity for stopping and he found that the air had already been exhausted from the train pipe.

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ice or emergency position, the effect upon the brakes would be, if they were partially applied by the leading engineer, to set them harder, or fully apply them,

"It is always rulable for the engineer on the second engine to cut in his brake valve, when, in his judgment, it is necessary to operate the brakes to avoid disaster, or when he has an emergency of which the leading engineer may be ignorant, but not otherwise, unless requested to do so by the leading engineer.

"On long down grades the leading engineer on a double-header might, by unskillful handling of the brakes, fritter the air away so that when the second engineer cut in his brake valve to assume control of the brakes, he would be powerless to aid in stopping, except by calling to the train crew for hand brakes, and by the use of his reverse lever."

Here is another case of divided responsibility. If the first engineer did not have his brakes fully applied, the second man is guilty of neglect in not cutting in

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