Brake Tests

32 Manipulation of Test Train. On Test TRACK. 66. In order to run the maximum possible number of tests per day and not delay the movement of trains in either direction, a pro- gram of the tests for each day was prepared on the day previous in accordance with the runs desired and the schedule of regular trains. A train sheet was kept, showing time as abscissæ and locations as ordinates, the time of regular trains being shown graphically at each station within the test train’s maximum movement, which extended north to Elwood and south to Atlantic City, the distance between the two points being about twenty-two miles. The location of the test train was recorded in the same way, so that the time best adapted for the various runs and train orders involved was clearly presented. Fig. 20 shows a typical record of this kind. 67. When making a test run the engineman endeavored to reach a speed sliglitly above that desired, just before entering the measured track. The throttle was closed just before reaching the circuit breakers preceding the zero point, no change being made in the position of the reverse lever. The train then drifted over the circuit breakers pre- ceding the zero point at which point the brake was automatically applied by the trip mechanism (Par. 41). At the instant the brake pipe exhaust started at the trip, the brake valve handle was moved to emergency position for all emergency tests and to lap position for all service application stops. When the engine and cars were to be stopped separately (break-away tests), the same procedure as above was fol- lowed, except that the coupling pin between the engine and tender was pulled out as soon as possible after steam was shut off. This per- mitted the engine to pull away from the train as soon as the brake application was made, providing the retardation of the cars was higher than that of the locomotive. However, the engine did not always separate from the train when making stops with low braking powers on the cars. On this account it was decided to use steam on the locomotive in such tests as soon as the coupling pin was pulled out, so as to get the locomotive away from the cars and permit the cars to stop without any possible interference on the part of the locomotive, the stop of the locomotive in such cases being disregarded. For such stops the flexible wiper and the tripping mechanism were on the first car instead of the locomotive. 68. When the train was within a given distance of the trip, a signal operator, located at the switchboard in the first car gave a signal to all the observers on the train, so that all instruments might be made ready to perform their respective functions during the test.