. The Street railway journal . ir of wheels of different diameters on the same axlesare running on a straight section of track the larger wheel willdescribe a circle round the smaller until the flange of the wheel en-counters the rail, when the smaller wheel must be dragged alongin this position. In order to overcome this tendency the tread ismade conical, as is well known. The larger wheel then only de-scribes a circle until the diameter of the smaller wheel has be-come so much greater that it equals the diminishing diameter ofthe larger wheel. In order, however, that this equalization maybec
. The Street railway journal . ir of wheels of different diameters on the same axlesare running on a straight section of track the larger wheel willdescribe a circle round the smaller until the flange of the wheel en-counters the rail, when the smaller wheel must be dragged alongin this position. In order to overcome this tendency the tread ismade conical, as is well known. The larger wheel then only de-scribes a circle until the diameter of the smaller wheel has be-come so much greater that it equals the diminishing diameter ofthe larger wheel. In order, however, that this equalization maybecome possible it is necessary for the flange to have the vieces-sary amount of play in the groove of the rail. If the flange be too thick this condition is at first of little im-portance in the case of new tires, which are evenly turned. Butvariations in the material used and also the wear due to curvesfrequently produce a small difference in the diameters. Whenonce a difference exists it rapidly increases as the smaller wheel,. DiraensioDs in Millimeters FIG. 2.—STANDARD WHEEL SECTION, NUREMBERG in consequence of the smaller leverage, constantly slides a little,and its thick flange does not permit an equalization. The flangeof the small wheel then always travels against the carrying rail,while that of the larger grinds against the guide rail. The wearthen assumes the form shown in Fig. i. At the same time theentire truck frame is twisted, as a rule, at an angle to the track,and the wheels diagonally opposite each other show equal formsof wear, although to a smaller extent. I do not believe that flange wear, as described above, isoften caused by the trucks being out of square, as if itwere the case, the truck would adjust itself to run obliquelyand the wheels, which always have some play in the axle-boxes, would run correctly. I have ascertained by meansof more than sixty measurements that the diameter of the 5. Poor measuring appliances, so that the error is presentfrom the f
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Keywords: ., bookcentury1800, bookdecade1880, bookidstreetrailwa, bookyear1884
