The Concluding
Page 55
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Conferences at Olympia
A Résumé of the Proceedings at Meetings Held Undor the Aus,Wces of Important Associations During the Closing Days of the Commercial Motor Show
Maintenance Costs and Successful Operation
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A FINE opportunity far engineers in the rail and roadtransport industries to exchange views was afforded at the Railway Companies' Association's Conference held last Thursday at Olympia. The proceedings were opened by Sir Josiah Stamp, G.B.E., chairman of the London, Midland and .Scottish Railway Co., whose place was, later, taken by Sir Harold Hartley. A most interesting and informative
address by Mr. J. Shearman, M.I.A.E., Road Motor Engineer, London, Midland and Scottish Railway Co., followed, and amongst those who took part in the subsequent discussion were : Mr. L. Pomeroy (Daimler Co., Ltd.), Mr. Coventry (G.W.R.), Colonel Scammell (Scammell Lorries, Ltd.), Mr. H. N. Gressley (L.N.E.R.), Mr. Tom Thornycroft (John I. Thornycroft and Co., Ltd.), Dr. H. F. Haworth (Leyland Motors, Ltd.), Mr. R. Clayton (Karrier Motors, Ltd.), Mr. Guy Jones (L.N.E.R. Co.).
Railway companies' vehicles, Mr. Shearman said, covered no more than between 5,000 and 10,000 miles per year and might easily make 100 stops per day. He quoted percentage figures of operating costs compiled on a 10,000-mile-perannum basis for 2-ton "quantity-produced," 2-ton " highclass " and 4-ton petrol lorries, and 5-ton oil-engined lorries. Standing charges amounted respectively to 9.4, 13.43, 13.9 and 19.18, whilst fuel figures were 14.1, 14.48, 14.4 and 2,44, and the repair percentages 15.5, 14.33, 11.1 and 11.09. At the 1934 rate, licence duties were 8.5, 9.12, 7.9 and 4.24.
He mentioned the absence of the need for a high powerweight ratio for railway work, and the importance of increasing the mileage and of keeping the vehicles tally employed. To help in the accomplishment of the last-named, he mentioned three ways—using interchangeable bodies, tractors and trailers, or quickly detachable articulated fivewheeled units.
On the subject of repairs, he said vehicles should be made as free from complications as possible. The majority of engine troubles he attributed directly or indirectly to cylinder wear. Synchronization of the time at which repairs fell duo was the most economical method of maintenance, but this was, at present, impossible except to a limited degree.
Some parts might be made less durable, others more so. Amongst the latter were cylinders, valves, guides, crankshafts, timing chains and piston rings. Brake drums, he said, lasted more than four times as long as shoe facings, thicker friction material would improve matters if hydraulic operation were employed. Progressive springs reduced chassis shocks when running with a light load. The ideal vehicle should be capable of running 1,000 miles or six weeks without attention.
Features that are Desirable.
Considering a typical " quantity-produced " chassis, he pointed to the many desirable features usually absent—detachable radiator tubes, detachable cylinder blocks and/or liners, permanently fixed starting handles, devices for keeping up engine temperature, means for elimination of tappet adjustment (instruments except an ammeter and mileometer), an automatic "off" switch for coil ignition, but, preferably, the use of magneto ignition in view of the fact that ignition current consumption with the former method may, at low speeds, reach 24 watts.
The L.M.S. specification for new vehicles palled for stopping distances from 20 m.p.h. of 40 ft. on the hand brake, and 30 ft. on the foot brake. It was surprising to find how Often they failed to reach even these reasonable standards.
Tyre sizes and weight distribution were not wholly satisfactory. He quoted an example where less than 3-ewt. of the
2-ton pay-load was carried on the front axle. He thought there were too many types and sections of tyre. He considered a small turning circle of gfeat importance. The maintenance engineer's ideal, he said, was the buildins of a standardized fleet, but it would be difficult to combine
standardization with advance in design. Manufacturers should consider this point, with a view to the installation of new components in old chassis.
He described briefly experiences with engines running on heavy oil, vaporizing oil and compressed gas. Except for their licence duty and higher first cost, he considered the mechanical-horse type of vehicle a "noble response" on the part of the manufacturers to the demand for a substitute for the horse itself in short-distance haulage.
The discussion was then opened by Sir Josiah Stamp., who, in doing so, stressed the need" for the exchange of opinion between manufacturer and operator.
Important Points from the Discussion.
The following points arose in the discussion:— Amongst the worst offenders in slowing down road traffic were the railway companies with their numerous horsed vehicles. Average electrical equipment was inadequate for vehicles in railway use making 100 stops per day and possibly working many hours in the dark. Parking brakes were insufficiently secure when heavy vehicles were left unattended on steep hills or at dock sides. Visibility to the sides and rear was not good enough when backing, etc.
There was need for further developing producer-gas plant, which had already been brought nearly to a practicable proposition. With regard to the remarks made by Mr. Shearman on the life of the vehicle being approximately 10 years, six years was a figure nearer the mark. Railways had big political influence and, accordingly, they should use it to have taxation ameliorated—at least on the class of vehicle of the mechanical-horse type. It was only taxation that kept the horses on the road.
In connection with building special vehicles for special conditions, only a small difference in specification was liable to upset production programmes. The cost of building vehicles to last a given period would be prohibitive. It would be impossible to combine reliability up to, say, 50,000 miles with the expiry of useful life at that distance. The practice of overloading induced by the present system of taxation encouraged the use of a 2-tonner as a 4-tonnerin other words—it produced, in effect, a bad vehicle, viz., a 4-tonner built for 2-ton loads, which would, obviously, be Incapable of giving satisfactory service.
There was no difficulty about installing bigger dynamos and accumulators. Oil lamps might well take the' place of electric equipment on the mechanical-horse type of machine. Greater use might be made of rubber for such parts as lamps and mudguards. Simplification in tyre sizes would be afforded if a given section were suitable for a given load. The lighting set, as it existed, was an expensive apparatus for performing a light duty.
At luncheon, to which the party was entertained by the S.M.M. and T., Lient.-Commander J. W. Thornycroft, who was in the chair, said that if manufacturers could not supply the railways with the vehicles they wanted, the railways might manufacture them themselves—a state of affairs that was quite illogical. In replying, Mr. H. N. Crossley, chief mechanical engineer to the L.N.E.R., informed the company that railway-traffic returns were showing improvement, which meant that there was movement, and movement by rail necessarily involved movement by road.