Читать книгу Locomotive Engine Running and Management онлайн

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In looking round an engine, it is a good plan to watch the different oil-cups to see that they are not working loose. Many cups that are strewed over the country could be saved by a little more attention. A cup flying off a rod when an engine is running fast becomes a dangerous projectile. I have known several cases where cups went back through the cab-window. I have also seen several cases where cups worked off the guides or cross-head, and got between the guides, doing serious damage. One instance was that of an engine out on the trial-trip. It smashed the cross-head to pieces, and let the piston through the cylinder-head.

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A sharp tap with a hammer on the tread of the cast-iron wheel will produce a clear, ringing sound if the wheel is in good order. The drivers can generally be effectively inspected by the eye. If oil be observed working out between the wheel and axle, attention is demanded; for the wheel may be getting loose. Moisture and dirt issuing from between the tire and wheel indicate that the former is becoming loose, and this is a common occurrence when the tires are worn thin. When a wheel is running so that the flange is cutting itself on the rail, something is wrong, which also demands immediate attention. Oblique travel of wheels may be produced by various causes. If the axles of the driving-wheels are not secured at right angles to the frames, and parallel with each other, the wheels will run tangentially to the track, according to the inclination of the axles. Violent strains or concussions, such as result from engines jumping the track about switches, sometimes spring the frames, and twist the axle-box jaws away from their true position enough to cause cutting of flanges without disabling the engine. Tires wearing unevenly in consequence of one being harder than the other, produce a similar effect. Where there are movable wedges forward and aft of the boxes, the wheels are often thrown out of square by unskillful manipulation of these wedges. Engineers running engines of this kind should leave the forward wedges alone. Sometimes the center-pin of the engine-truck gets moved from the true central position, leading the drivers towards the ditch. Diagnosing the cause of wheel-cutting is no simple matter, and it is a wise plan for engineers to allow the shop-men to devise a remedy.