No Waste With Waste-paper Transport
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by P. A. C. Brockington, A.M.I.Mech.E.
THE regular collection of waste paper is an all-important factor in the economy of a manufacturer, because a build-up of waste can literally "choke the works" or necessitate a high expenditure on incineration or other means of disposal. To paper mills, graded waste represents a basic raw material and supplies must be guaranteed. Although loads of waste paper have a relatively low value, efficient transport facilities are, therefore, all-important to the provider and consumer.
The 35-vehicle fleet of J. Ainsworth and Co. (Bolton), Ltd., Beehive Works, Folds Road, Bolton, waste-paper merchant, is used for the collection of waste in an area extending from Aberdeen. to . the main population centres of Devonshire. and deliveries of graded paper cover substantially the same area. Waste is sorted at the Ainsworth factory into 39 grades.
On average each vehicle covers about 50,000 miles in the year, whilst one vehicle has completed a total of more than 850,000 miles and several have covered over 500,000 miles. According to Mr. R. C. Ainsworth, guiding principles in the operation of the fleet are based on regular servicing. efficient maintenance (as distinct from preventive maintenance) and vehicle cleanliness, which applies to the engine and chassis, as well as the bodywork.
Fleet Make Up
A total of 17 Albion Chieftains of 61-7-ton capacity are included in the fleet, and also an Albion Reiver maximumload six-wheeler and a Claymore 5-tonner of the same make. The remainder of the fleet mainly comprises E.R.F. 44G 8-tonners, exceptions being two E.R.F. six-wheelers',. a Leyland Comet, two Bedford 4-tonners and a Bedford TK 10-ton tractor. A Bedford Workobus is employed for the transport of personnel and small loads of material.
Waste is collected in bales, bags, tares, paddy cases, sacks and bundles, or located on pallets, and is loaded manually or mechanically according to the suppliers' facilities. Drivers have therefore to be well versed in loading techniques, and they need a long period of training before they are fully competent to tackle the more difficult jobs. The one-vehicle-one-driver rule is applied throughout the fleet, apart from the six-wheelers. Heater and demister equipment is installed in all cabs, which are also fitted with an interior mirror. Flashing indicators are controlled by a time-return switch.
Unloading and loading in the workshops are performed by Coventry Climax fork-lift trucks, fitted with squeeze clamps, or by manhandling direct on to a belt conveyor. Fork trucks are also used by the majority of paper mills for handling the waste, which can be loaded at the rate of 13-14 tons in 15 min. by this means. Extended operation of vehicles equipped with all-plastics, all-aluminium and composite plastics-aluminium-timber cabs has shown that the composite type competes with the aluminium cab for first place in terms of long life and ease of repair. In the event of localized damage, plastics cabs can readily be repaired with the kits provided by the makers, but more serious damage is more likely to reduce the structure to scrap value than with other types.
Several of the E.R.F. 44G 8-tonners are equipped with Jennings composite cabs, which are based on timber frames and have plastics roofs with bonded-in longitudinal reinforcing members of the same material. Fitted with dual headlights, the quarter-panehsections are of compli cated shape and the use of glass-fibre for these parts is fully approved because their multi-curved form combines strength with resistance to local impact. Apart from the roof the remaining panels of the cab structure and doors are of aluminium. The results of major accidents have shown that badly damaged cabs of this type and of all-aluminium construction can generally be repaired by the makers at a reasonable cost, whereas the damage caused by a heavy impact in the case of an all-plastics cab cannot be economically repaired because the entire structure tends to distort. Metal or steel mudguards are preferred to plastics wings because they provide a higher resistance to abrasion by mud or stones.
Because of the bulky types of load carried, the vehicles normally operate well below their rated weight-carrying capacity, but the loads have a high centre of gravity and lateral weight transfer on bends increases the stress on the outer side of the vehicle platform. If reducing body weight to a minimum provided an increased payload, all-aluminium bodies would be mainly employed, but as a reasonable weight tolerance is acceptable, existing light-alloy bodies are being progressively replaced by the timber type with aluminium chock rails.
The tiniber bearers of these bodies offer a greater resistance to bending when the body is subjected to cornering stresses (possibly, it is considered, because there is less resistance to compression) and the ease with which knee irons can be attached to the frame members and floor to support the headboard is of particular advantage. A high, robust headboard is required to prevent movement of the load under heavy braking forces, and it is advantageous to fit a board that can be easily straightened.
The six-wheelers are employed on overnight runs to a depot of Glasgow Corporation to collect waste on a contract basis, the vehicles travelling empty on the outward.run. On alternate days the vehicles are employed for local deliveries and collections.
Because of the length of the load on a six-wheeler, two winches are fitted to the rear of the platform bodies to enable the load to be lashed down with 1-in. ropes in a fore-and-aft direction between the headboard and winches, as well as transversely. At Glasgow the bales are loaded by hoist.
An interesting experiment in economy that has proved a notable failure relates to the application of a six-speed gearbox with overdrive top gear to two E.R.F. 44Gs in .conjunction with a 5.62 to 1 final drive. This increases the maximum speed of the vehicle from 42 m.p.h. to 56 m.p.h. and improves the average fuel consumption from 18 m.p.g. to 20 m.p.g., compared with the standard vehicle with a direct-drive gearbox and a 4.82 to 1 rear axle.
Despite the favourable improvement in fuel consumption, the higher speed potential ot the vehicles has, however, been costly with regard to overall running costs. Whereas the vehicles with direct-drive cover 90,000-95,000 miles on a set of tyres, the covers of the overdrive vehicles have to be replaced after 45,000 miles and brake-liner life is also reduced. Front and rear brake liners of the slower vehicles are renewed at mileages of 75.,000 and 110,000 respectively, which compare with a front-brake mileage of 40,000 and a rear-brake mileage of 65,000 of the overdrive vehicles, whilst other disadvantages of a higher speed potential include increased shackle-pin wear. Because the overall cost of using overdrive is a serious economic factor, both vehicles will be fitted with standard transmission units in the near future.
Fuel consumption of the Albion CH.3 7-tonners is 20.2 m.p.g., and it is notable that the chassis are equipped with "six-speed gearboxes and hub-reduction gears. The Gardner 6LX engines of the E.R.F. six-wheelers return a consumption of 14.3 m.p.g., whilst the consumption of the Albion Claymores and Albion 61-tonners average 24 m.p.g. and 17 m.p.g. respectively. Of the remaining vehicles, the Leyland Comet averages 14 m.p.g. and the Albion Reiver about 10.42 m.p.g., the consumption of the Bedford rigid vehicles being about 25 m.p.g.
All vehicles are equipped with I4-ply tyres and no remoulds are used, except in the case of the Michelin Metallic D.20 tyres fitted to the six-wheelers. The lubricating oil of new or reconditioned engines is changed at 500 miles and 1,000 miles. and thereafter at 1.000-mile intervals up to 3,000 miles. Changes are then made every 3,000 miles for the life of the engine. Every commercial vehicle in the fleet is run on an-identical, type of multi-grade nil, and the same lubricant is used for staff cars and so on. Tt is considered that this lubrication policy plays an impor
416 ' tant part in prolonging the life of the engines between overhauls.
Particular tribute is paid to the properties of Marfak grease, which is used for chassis lubrication every fortnight or, if possible, at more frequent intervals. In the words of Mr. Ainsworth, " Marfak obviates the necessity of using a sledge-hammer for removing king pins and shackle pins," and the example is given of stripping the shackle pins of a vehicle after 273,000 miles for micrometer measurements of wear. Of the 12 pins, only two had to be'replaced, and these showed a wear of 0.009-0.012 in.
As indicated earlier in this article, vehicle cleanliness of the highest order is regarded by Mr. Ainsworth as an essential element of efficient fleet operation. There are five steam supply points inside the main garage building, fed by a Clayton steam generator, which is also uSed foi space heating of the garage and works. Vehicles are thoroughly cleaned every week, and particular attention is given to this aspect of maintenance when Mr. Ainsworth personally checks the vehicles when they are all assembled for inspection on Sundays.
Top Priority for Brakes
Brake efficiency is given top priority, regular tests being made with a Tapley meter and on a Weaver brake-testing machine of the dual-plate type, a valuable feature of the latter being that it can be employed for separate tests of nearside and offside brakes. The "pass" efficiency of the brakes of an unladen vehicle is 70 per cent., whilst a laden vehicle is required to show an efficiency of 45-50 per cent Nearing completion, a new servicing bay is designed tc accommodate all types of vehicle from the smallest car te maximum-load eight-wheelers, the bay being run iri conjunction with a jointly owned service station. Space i! provided for three eight-wheelers or six medium-si.a commercial vehicles or eight small cars.
In effect, the bay provides three full-length pits, but ir fact it comprises a floor supported by pillars, with rectan gular openings of the normal pit type, free movement beini provided throughout the underfloor area. An open spaci on one side will be employed as a sunken workshop. .4ei monorail hoist is available for lifting an engine, cab 91 other major component.
. Particular regard is paid to the drivers who return to Ili( depot late in the day, or who end their run in a nearb! centre. It is fully appreciated that making use of publii transport or walking several miles to reach their home: can represent a wearisome extension of the working da] and may dislocate domestic arrangements. and use regularly made of the Workobus to provide personal trans port for drivers