NECESSITY FOR KEEPING BOXES AND WEDGES CLEAN.
The growing practice of close and stated inspection of locomotives to detect defects, before waiting for them to develop into breakages that cause trouble and delay to trains, will give especially good results if applied to boxes and wedges. If the wedges are taken down and examined at regular intervals, the ridges that appear so readily on the face, when oil-grooves are cut on the sides of the driving-box, can be smoothed off before they cause distortion of the surface. This is also a good time for a thorough cleaning of the pedestals and box, and the oil-holes can be examined and opened out properly. Work of this kind often prevents boxes getting hot on the road, with all the entailed delay and expense, which frequently include changing engines if the train must be pushed on. One turn of a hot box will often wear a brass more than the daily running for two years.
TEMPERATURE OF THE BOX TO BE CONSIDERED.
One condition of the box to be considered, when adjusting wedges, is its temperature at the time the work is done, and what that will be when the engine is in service. Adjusting wedges is often done as a preliminary step to lining and adjusting side rods; and this is done, on many roads, on the shop-day when the locomotive is in for washing out and periodical repairs. At that time, the engine being cold, the boxes will be at their lowest temperature, and, consequently, at their smallest dimensions. Allowance should then be made with the wedges for some expansion of the boxes. Another condition that should be considered, is how the box has been running. A box that has been running hot or warm, generally compels the wedge to be lowered to allow for extra expansion. When this box has been repacked, or otherwise cared for, the wedge is again set up. While doing this, it should be remembered that a box that has been running hot is liable to be distorted, and its journal bearing injured, so that it is likely to run warm for some time, till the brass comes to a smooth bearing. If the wedge will not permit the box to expand, it binds the journal, and is likely to run still hotter, and is liable to stick in the jaws.
SMALL DISORDERS THAT CAUSE ROUGH RIDING.
Many complaints are made about pounds in driving-boxes and wedges, when the trouble really exists elsewhere. Boxes with driving-spring saddles whose foot is but the width of the top or spring-band, will oft-times, if the band is not rounded where it rides on the saddle, or is not fitted with a pin or other center bearing, tip on the box with each motion of the spring. Or, if the saddle is moved from its worn seat on the top of the box, it will rock and pound. Again, obstructions in the bearing of the spring equalizer that will prevent the full motion of the springs, and bring them to a sudden stop, will produce a motion resembling that caused by a stuck box. Attention to details that are sometimes considered the crude parts of a locomotive, will often prove highly beneficial to the working of the locomotive; and especially is this the case with the parts that transmit the motion of the springs.