Railway truck

“ With a narrow-gauge type there would, of course, always be the time and expense of transhipment to or from the ordinary railway trucks in the same way as with the road carts, but the time and expense may be lessened by so constructing the little narrow-gauge trucks that the bodies may be readily lifted off the frames and wheels, and be placed like packing-cases in the railway waggons.
It is natural to look to the railways of the first rank for the latest advances in construction, appliances, and equipment, and it is generally there they are found. ”

“ Necessity truly became the mother of invention.
The first, and most far-reaching, invention was that of the swivelling truck, which, placed under the front end of an engine, enables it to run around curves of almost any radius. This enabled us to build much less expensive lines than those of England, for we could now curve around and avoid hills and other obstacles at will. The illustration opposite shows a railroad curving around a mountain and supported by a retaining wall, instead of piercing through the mountain with a tunnel, as would have been necessary but for the swivelling truck. ”

“ The conception of a truck or other vehicle that shall practically carry its own rail-road has been an attractive one to some inventive minds. In sandy regions, and in other places where a railway track is difficult to maintain, [Pg 117] and where, at any rate, there would hardly be sufficient traffic to encourage expenditure in laying an iron road, a very great boon would be a kind of motor which would lay its own rails in front of its wheels and pick them up again as soon as they had passed. ”

“ Therefore, instead of resting on the two sides of the truck, locomotives are made to bear on the centre of it, so that they are carried on it and on the two fulcrums of the equalizing levers, which gives the machine the adjustability due to the three-legged principle. When more than four driving-wheels are used the springs are connected together by equalizing levers, as shown in Figure 29 (p. 124) , which represents a consolidation engine as it appears before the wheels are put under it.
Having a vehicle which is adapted to running on a railroad track, it remains to supply the motive power. ”

“ On our home and continental lines, the modern express locomotive, with a four-wheel bogie truck in front, is a much longer vehicle than its predecessors, and its total weight is distributed over a greater wheel-base; but the actual weight placed upon the driving-wheels, or on the coupled wheels, is now very much in excess of former practice, and must be taken into consideration when working out the details of girders and cross-girders of under-line bridges. ”

“ The Bissell bogie, or safety truck, for locomotive engines, so much prized on American and foreign railroads for the great safety and economy it affords on curved roadways, after [Pg 217] years of probationary trial in England, has at length been adopted by John Fowler, Esq., C.E., F.G.S., upon all the new engines, eighteen in number, now working on the Metropolitan Railway, and by Robert Sinclair, Esq., C.E., upon twenty new eight-wheeled engines on the Great Eastern Railway, which may be seen daily. ”

“ Very complex and difficult is the real problem. A large portion of the traffic of the country is carried in trains which pick up and set down wagons at intermediate stations. In the same truck may be goods of all classes and different quality or bulk for different destinations. One article of great bulk and light weight may be carried in a truck by itself or along with articles of great weight and small bulk. ”

“ The swivelling truck was first suggested by Horatio Allen, for the South Carolina Railway, in 1831; but the first practical use of it was made on the Mohawk and Hudson Railroad, in the same year. It is said to have been invented by John B. Jervis, Chief Engineer of that road.
The next improvement was the invention of the equalizing beams or levers, by which the weight of the engine is always borne by three out of four or more driving-wheels. They act like a three-legged stool, which can always be set level on any irregular spot. ”

“ In this connection I may mention the well known Robinson Radial Car Truck, which is in quite extensive operation on electric railways. This is the only car truck, I believe, ever designed and constructed on correct mechanical principles. It is so constructed that every axle in the car or train becomes exactly radial to any curve around which it passes, all the axles becoming parallel on straight lines only. This prevents wear and tear and grinding and derailment on curves. It also greatly economizes current. ”

“ The English railway companies, who are now able to follow their rolling stock almost with the naked eye, who know exactly how long each truck will take to run the short distances in their island, who can, therefore, provide proper loads both for the up and down journeys, hence making the best use of their stock, and who are always aware in whose hands their trucks are, will suddenly see a great number of them disappear out of their sight and beyond their control on long journeys and unknown routes. ”

“ In railway engineering it is applied to an under-truck, most frequently with four wheels, which is often provided at one end of a locomotive or both ends of a carriage. It is pivoted or swivelled on the main frames, so that it can turn relatively to the body of the vehicle or engine, and thus it enables the wheels readily to follow the curves of the line. ”

“ For accelerating transportation railway trucks provided with flaps are used, which make of the whole train a single platform. At the rear of the train is a plough which can be drawn by a wire rope attached to a drum carried on a special car in the fore part of the train. ”

“ When the car is loaded the machine can either move on to the next car, or pull it under itself into place. With the help of four men it can load from 125,000 to 150,000 feet of timber in a day. By means of the cable it can make up a train, and then by lowering the truck and raising the legs out of the way, it is converted into a locomotive and hauls the train away to the mill or railway station at the rate of three or four miles at hour.
As forests are cut away along the water courses, railways have to be resorted to more and more, Fig. ”

“ To Couple with Standard Railway Equipment
High Hercules Logging Truck
Designed to Couple with Standard Railway Equipment. Two feet, ten inches from Rail to center of Coupler.
MADE IN CAPACITY OF 70,000 LBS. PER SET OF TRUCKS
This cut shows our Class G-2 Truck, No. 125, which is equipped with Hercules Patent Bunk 9 feet long and Knight Patent Chock Block.
Multiple Boring Mill
33-inch Chilled Cast Iron Wheels and Axles with 41⁄2 × 8 inch Journals. ”

“ Designed for well-ballasted track with large-radius curves and gentle gradients, they all too frequently left the rails, and the unsuitability of the essentially rigid British design soon became apparent.
The challenge posed by the American roadbed was met by American mechanics. By the mid-1830’s a distinctive American locomotive had evolved that might best be described by the word “flexible.” The basic features of its running gear were a bar frame and equalizing levers to provide vertical relief and a leading truck to provide lateral relief. ”

“ In order to carry the weight of the firebox, which, with the new driving wheel location, overhangs the rear driver too much to be properly supported, a two-wheel trailer truck was used. This trailer truck, which is fulcrumed a short distance back of the main driver, is so designed that it has lateral motion, and provision is made for ash pan as well as firebox clearance.
By the use of higher steam pressure, larger heating surface and grate area, the use of passenger locomotives of the three-coupled type, with the troubles incident to the use of long parallel rods, was put off for a decade. ”

“ But as the decade advanced, the need grew for heavy freight engines that could be safely run at speed. Without a pilot truck, the leading driving axle of the freight engine was generally overloaded. While the application of a 4-wheel truck reduced this front-end overload and permitted faster running it materially reduced the traction of the drivers by bearing too great a portion of the total weight. ”

“ Visitors disembarking from the London & North-Western express at Portmadoc, and seeing the diminutive engine and trucks drawn up alongside on their own road and completely dwarfed by the towering rolling-stock of the standard-gauge line, cannot repress a smile, for the engines, cars, trucks and wagons are no larger than are used upon the larger-sized model railways devised to-day for the amusement and education of the young.
Yet it is a complete pocket edition of the familiar railway, and its capacity is amazing. The engine provokes interest, for it is no taller than an average-sized person. ”

“ The carriages are mounted on bogies, and have been completely equipped with carriage springs, grease boxes for the axles, spring buffers, draw-bars and screw couplings right and left. The two corridor carriages have the proper extending covered ways.
The goods train is quite as remarkable in its way as every other part of this railway. It is composed of ten trucks and vans, and has besides a guard's brake-van fitted with a screw-down brake of the usual sort. There are two high-side trucks, four medium, and two low ”

“ The cars and wagons are on the same scale, and the first impression of the diminutive iron horse awakens doubts as to whether it is safe to trust oneself to its care. But see that self-same engine busy at work hauling a train of 7 passenger coaches, a guard’s van, 10 goods wagons and 100 or more empty slate trucks, stretching out for a length of 1,200 feet and representing a total load of 110 tons, out of Portmadoc, bound for the quarries, and disdain gives way to complete admiration. ”

“ Track in bad condition will also tend to increase the wheel resistance, and improperly constructed trucks and wheels will entail the use of more power to move the train. Where trucks are so defective that they do not maintain the wheels revolving in parallel planes, the flanges of some of the wheels will rub on the rail, increasing the resistance. Wheels out of round; those having the axle out of center, however slight; wheels of different size on the same axle; and numerous other car-truck disorders,—all contribute their share in making a train pull hard. ”

“ Under such strain the truck wheels are particularly likely to leave the rails when they encounter an obstruction. Once derailed, the truck would then spin around on the deadly center pin, throwing the locomotive over.
In effect, then, the center pin of the conventional truck extended the rigid wheelbase of the engine, and caused the truck to act much as would a single set of leading wheels fitted rigidly to the engine frame far ahead of the front driving wheels. ”

“ To enable the engines better to adapt themselves to the flexures of the road, the front and middle pairs of drivers are held in position by wrought-iron beams, having cylindrical boxes in each end for the journal-bearings, which beams vibrate on spherical pins fixed in the frame of the engine on each side, and resting on the centres of the beams. The object of this arrangement is to form a truck, somewhat flexible, which enables the drivers more readily to traverse the curves of the road. ”

“ A brisk, bright-faced young fellow glided from their midst, cleared an obstructing truck with a clever spring, stood ready to greet the locomotive and express car as they parted company from the passenger coaches, and ran thirty feet along the siding to where the freight-sheds stood. ”

“ Note that the V’s, and thus the point of bearing, are slightly in front of the center line of the truck axle. It was suggested in the patent specification that the V’s might be placed to the front, rear, or directly over the axle, but in most actual applications they were placed directly over the axle. Note also that the locomotive shown on the figure is obviously a standard high-wheel American type which has suffered the rather awkward substitution of a pony truck for its regular 4-wheel arrangement. It is probable that few if any American types were so rebuilt. ”

“ It met the competition of the gasolene locomotive upon the highroad, how? By cutting its all-the-year train service to two trains a day and gradually raising its fare to five cents a mile. People who have to go from one end of its main line to the other, about 110 miles, are still likely to patronize it. The motor-bus is hardly more effective in the long haul than is the motor-truck. And in the really bleak days of winter its snug little passenger-cars, well lighted and warmed, have more appeal than the poorly lighted and heated motor-buses that traverse the State highway. ”

“ Usually there is not only a saving in time when a mechanical device is used but the amount of expensive manual labor is decreased.
Among the practical devices used are removable bodies. The whole body of the truck may be swung by means of a crane from the chassis to a platform where it is loaded or unloaded while the truck with another body is proceeding on its way. Other bodies are so arranged on rollers that they may be readily rolled from the chassis to the platform. Railways are also taking advantage of removable bodies for the shipment of less than car-load lots. ”

“ All makes of trucks are more or less alike in general construction, differing only in minor details, so that the personal whims of the buyer will largely determine the kind he will select. It is advantageous to have as long a distance as possible between the driver’s seat and the bunk over the rear axle, in order to allow more of the load to be carried by the truck, and less by the trailer, giving better traction to the drive wheels, but necessitating extra strong rear springs and axles. ”