The Locomotive Of Today

The Framing, Wheels, etc. : Hornblocks, etc. 127 sufficient to hold the stay up, lugs upon each side of the jaws also keeping them from opening; but when laminated springs are used, and are not in any way fixed to the hornstay, it is usual to have three or four bolts on each side, with split pins to secure the nuts upon them. Webs are carried from one flange to the other at right angles to strengthen them. The frames have been found by experience to be weakest at the corners of the gap cut out for the guides, especially when fitted with hornblocks with no wedges, so that the ■corners of the castings are well thickened up, and no bolt holes are located on this line of weakness. Instead of being cast in one piece, the hornblocks are •often cast in pairs, one piece being fixed on each side of the gap in the frame, there being no connection between them at the top, except by the frame itself. This method is only used in places where the wheels are simply carrying- wheels, as in single leading and trailing wheels and bogies. They are cheaper to make and machine, but do not support the frames at the corners, and are therefore unsuitable for the coupled wheels. An arrangement is shown at B adaptable for outside leading or trailing bearings with overhung springs, the horn- stay not being suitable for underhung springs, as it simply, consists of a long bolt passing through a hollow distance piece of the proper length to lit between the jaws. It is most important that the faces of the hornblocks on each side of the engine shall be accurately in line, this can be proved by means of a long Steel straight-edge held to the faces after they are filed up or otherwise finished; to ascertain that they are square with the frames, a long square is held upon this straight-edge and tried with the lines stretched parallel with the frames on either side. If they should happen to be out of winding they must be adjusted by removing metal from one or other face as required and refacing them. A plumb line and square held to the face proves its perpen- dicularity. Axleboxes are made of gunmetal throughout, or of cast iron or Steel with gunmetal bearings fitted to take the journal, the shapes being very varied. At C a gunmetal box, suitable for driving or coupled axles, with a hornblock as at A, is illustrated in section and elevation. The sliding faces on each side are of the same width apart as the jaws of the guides, and have flanges upon each side to guide the box sideways. It is turned out at the crown to take the axle journal, and closed in at the bottom by a cast iron or Steel keep or oil cellar. A stout pin is passed through holes in the legs of the axlebox, and upon it are placed two eyebolts which