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Valve to Excess-Pressure Governor Top.-If this pipe breaks en route, place the automatic brake-valve on lap, and quickly plug the pipe toward the brake valve; then move the brake valve into release position for about three seconds, and back to running position. Results will be the same, then, as after remedying for the last mentioned defect, the high-pressure governor top regulating the pump's action.

Main-Reservoir Pressure Pipe (direct) to HighPressure Governor Top.-Plug this pipe, when broken, toward the main reservoir, and go right along; but as the excess-pressure governor top then exercises the only automatic control of the pump-and it only when the automatic brake-valve is in release, running, and holding positions, when the brake-valve is in lap, service, or emergency positions, the gauge hand indicating main-reservoir pressure should be watched, and if it begins to get too high the steam should be eased off from the pump by closing the throttle at the boiler, as far as may be necessary.

Reducing-Valve Pipe.-Rupture of this pipe has a farther-reaching effect than merely in cutting off the supply of pressure to the independent brake-valve, and possibly the air-signal system. Stop the flow of air from the broken pipe, by turning the adjusting nut so as to loosen the regulating spring of the reducing valve, until the blow of air ceases. Letting it go at

Broken Pipes

that, it would also be impossible to secure an automatic application of the locomotive brake; and the further remedy is to plug the broken pipe toward the independent brake-valve, and plug the exhaust port in the bottom of the brake-valve. The independent brake-valve is then valueless, except as a fixture, the handle of which must not be moved from running position; but the operation and holding power of the automatic brake of the locomotive will not be affected.

Pilot Section of Brake Pipe.-An angle cock is not generally used at the pilot end of the brake pipe, an angle fitting taking its place, and a cut-out cock is placed in the brake pipe back of the engine cylinders. Therefore, when coupling to a train in front of the locomotive, it is not uncommon to find that the pilot section of this pipe-forward of the cut-out cockis broken. In such case, when it becomes necessary to couple the air from the locomotive to the train ahead —and there are no cars behind-use a combination hoseto connect the brake hose and signal hose together at rear of tender, and open their angle and cutout cocks; use the other “combination hose” at the pilot, to couple the signal hose from the engine to the brake hose of the car; open the angle and cut-out cocks in the connected line at the pilot, and close the cut-out cock in the pressure-supply pipe to the airsignal line, and the locomotive and train brakes are

then under regular control by the operation of the automatic brake-valve.

TESTING.

For use in making roundhouse tests of the E-T equipment, a test gauge with a discharge cock (use a 1-inch release cock), a 1-inch brake-coupling, and a signal coupling, the couplings with threaded shanks connecting to two of the openings of a {-inch 3-way cock, and the gauge at the other opening. First, connect this testing instrument to the brake hose-coupling at rear of tender, or at the pilot, with the automatic brakevalve in release position; open the angle cock, and set the 3-way cock so the test gauge will receive the pressure, and close the small discharge-cock on the testing instrument; then see that the red hand of the large duplex gauge, and the black hands of both air gauges, register together, and to correspond with the

or note any errors-a variance of two pounds demanding correction of the gauge. Have some one then to make a service reduction, reducing the brake-pipe pressure to about 10 pounds below norrnal (to 60 pounds), and then to replace the automatic brake-valve handle in running position—this to test the sensitiveness and the adjustment of the feed valve. Note the rise of the hand on the test gauge, which should stop at 70 pounds. Then open the small release cock

test gauge;

Testing No. 6 Equipment on the testing instrument, and consider the action of the hand on the test gauge; if it fluctuates, falling as much as 2 pounds or more, or shows a slow overcharge of the brake pipe, the feed valve should be cleaned and oiled.

Next, connect the testing instrument-release cock closed—with the signal-hose coupling at front or rear of the locomotive; set the 3-way cock to receive that pressure, and open the signal line cut-out cock; place the independent brake-valve in application position. and compare the indications of the red hand of the small duplex gauge with the hand on the test gauge; this also shows the adjustment of the reducing valve, and to test its sensitiveness open the small discharge cock on the testing instrument and watch for fluctuations, same as in case of the feed valve.

To test the pump governor: with automatic brakevalve in running position note that main-reservoir pressure is registered 20 pounds (or the amount of excess pressure to be regularly carried) higher than brake-pipe pressure, correcting any error in this by readjustment of the regulating spring of the excess-pressure governor top. Then place the brake-valve handle in the lap position, in which the red hand of the large duplex gauge should register the higher, or maximum, mainreservoir pressure that is standard for the class of engine.

Testing the automatic brake-valve, first make a 5-pound service reduction and lap the valve; if the black hand of the large air-gauge continues to fall, slowly, and there is a blow of air from the equalizing-discharge port under the brake valve, there is a leak of equalizingreservoir pressure, which must be stopped before proceeding further. Afterward, make a 20-pound service reduction of brake-pipe pressure, lap the brakevalve, and close the double-heading cock beneath it; if, then, the black hand of the large air-gauge gradually rises, it indicates a leaky rotary valve, or a leakage in the middle gasket, 18, of the automatic brake-valve.

Test locomotive brake-pipe leakage by making a 7-pound service reduction, lapping the brake-valve and closing the double-heading cock beneath it; then time the fall of brake-pipe pressure as indicated by the black hand of the small duplex gauge, and which should not exceed 5 pounds in one minute.

To test for locomotive brake cylinder leakage, make a full-on application by the independent brake-valve, close the cut-out cock in the main-reservoir supply pipe to distributing valve, and note the brake-cylinder leakage as indicated by the red hand of the small duplex gauge. To find out which of the brake cylinders are leaking, shut off each one in turn by closing its individual cut-out cock and timing the fall of the cylinderpressure gauge hand; when the fall of pressure is materi

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