The Locomotive Of Today

The Framing, Wheels, etc. : Bar Frames. 123 attached by angle irons, so that the firebox itself becomes the frame for the remaining length of the engine. This is done in order to get in as wide a firebox as possible. Fig. 25 gives an arrangement of bar framing as employed in America, it is shown for an engine with a leading bogie, four-coupled driving wheels, and outside cylinders with the steam chests on top, and the valves actuated by rockers. A is a side elevation, at the front end the leading bumper is fixed, and to this the pilot, or cowcatcher is securely fastened; two lugs are formed upon the upper sides of the bar frames for the reception of the cylinder castings, which are carried across from side to side and form a frame stay there; the guide yoke, or slide bar bracket also reaches across and carries the slide bars on the outside of the frames and a plate between, which forms a support for the boiler. Another stay and boiler support is placed just behind this, in front of the driving axle. Close to the trailing axle is a fourth cross-stay, and the trailing" end is closed in by a casting which connects the end portions of the frames together, and takes the tender draw gear and buffing attachments. The frames are each in two portions, the front carrying the cylinders, rockers, and reversing shaft brackets and the main portion carrying the axle box guides, or as they are called the “ pedestals ” ; these are formed of the same bars, but spread out a little wider than the other parts to form a better wearing face for the axle boxes; gibs or liners, usually made vertical, are fixed to the face nearest the cylinders, the other face being inclined and fitted with a wedge for adjust- ment; the bottom of the gap is closed and held from spreading by means of a clamp or hornstay. Two arms project forward from the driving pedestal, and between them the front frame is placed and held by wedges and bolts, a foot upon it also being butted up to the pedestal and fixed there. In many engines, especially those having more than two pairs of coupled wheels, the main frames are built up and bolted together, instead of being welded as in the example, so that in case of failure or collision the damaged portions may be the more easily taken out and replaced than would be possible with whole frames. The front end is especially liable to accident, by head end collisions, and is therefore made so as to be detached without disturbing the main frames. From the driving to the trailing pedestals, the frames are doubled, the upper bar being called the top rail and the lower one the bottom rail; they are stayed together vertically by blocks placed between them and fastened to each ; these form convenient means for the attachment of the brake hangers, etc.,