A Treatise on the Locomotive and the Air Brake Volume 3 (Paperback)

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1901 Excerpt: ...If the pressure is pumped in the usual time, during which the pump shows no sign of disorder, the presumption is that it is in good condition and no further tests will be necessary. If, on the other hand, the test shows that the pump is not in its normal condition, the trouble may be due to (1) leaky piston packing-rings; (2) receiving valves leaking; (3) back leakage from main reservoir; or (4) the air valves may be stuck. Tests, as in Art. 12, Part 2, should be made to locate, the cause. 10. Pump Governor.--The pump governor should be tested to see whether standard pressure is obtained when it stops the pump, also to see whether it will start the pump promptly when a light reduction of not more than 2 pounds is made in the pressure that operates the governor (see Art. 24, Part 1). If the pump stops either before or after standard pressure is obtained, the governor should be adjusted, by means of the adjusting screw 8, until it regulates the pump properly (see Art. 35, Part 2). If the governor does not start the pump promptly when a slight reduction is made, it may be due to a leaky diaphragm valve or to the relief port e being stopped up. 11. Brake "Valve.--The brake valve should be tested for leaks from the main reservoir into the train pipe. This can occur only through the main slide valve, so that a test for a leaky main slide valve should be made according to the method given in Art. 37, Part 2. Next, the excess-pressure valve should be tested to see if it is tight, and the excesspressure spring to see if it has the proper tension. The excess-pressure valve and spring may be tested according to the method described in Art. 35, Part 2. It is important that the equalizing piston be absolutely tight, and also all the connections leading from the bra...