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Ensuring a Canny Buy
Page 171
Page 172
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THE continued expansion of the motor industry, with increasing sales both at home and abroad, has been the major industrial success story of recent years. In achieving this success the range of vehicles offered to the public has correspondingly continued to widen as the total number of units produced has increased, This trend has applied to commercial vehicles as well as to cars, whilst, in addition, variations in body style have resulted in an even wider range of commercial vehicles.
In the comprehensive tables. of "British Vehicles For The World ". published annually in The Commercial Motor early in tvlay. around 1,500 basic commercial vehicle chassis are tabulated. Superimposed on this large total there could be virtually limitless variations in the specification of an individual vehicle resulting from a particular user's choice of, say, engine. gearbox or tyre equipment. Also, as distinct from alternative specification, some purchasers may wish to specify additional equipment, whilst, as already mentioned, there is practically no limit to the types of body which individual operators may require and which a virile industry can supply.
Wide Range Available With such a wide range available it would be unfortunate for the supplier and the subsequent operator if the wrong choice was made as a result of confusion arising from the very wideness of the choice available. However irrational may he the attitude when such a bad " buy " was made, in the opinion of the operator the unsuitability of the vehicle for the job would reflect adversely on the manufacturer eoncernc..!. Meanwhile, the unfortunate operator will be faced with the dilemma of running a vehicle which is uneconomic for the particular job on hand, or cutting his losses by an otherwise premature exchange of vehicles.
By definition a commercial vehicle is purchased to do a particular job of work, which will largely determine the type required. In contrast to the p.s.v. operator, whose problems of variation are concerned with numbers rather than types, the goods vehicle operator has often so many variations of traffic to contend with that at best any solution to his problem must largely be one of compromise. As in all cases. however. *here can be exceptions, and an obvious and increasing example concerns the conveyance of specific liquids in bulk.
But despite this growing interest in an increasing range of traffics being conveyed in bulk, a substantial proportion of all goods traffic moved is still conveyed on platform vehicles which, though relatively simple in construction, offer the major advantages in competitive road transport operation of flexibility and economy.
Comparable with the division of road transport organization into traffic and engineering departments, the selection of a suitable vehicle can be considered under a similar division of items. The traffic or goods to be carried by the proposed vehicle must obviously be the prime factor in selection, but there can be several contributory items to this main factor.
Probably the first such item to be determined will relate to the average weight (or number of consignments in the case of smalls or parcel traffic) to be carried. Driver's wages represent a high proportion of the total cost of operating a commercial vehicle. Moreover, this proportion increases relatively as the size of the vehicle decreases. On this score alone, and assuming funds are available, it is more economic in terms of cost per ton or consignments to operate larger vehicles, but here again other factors have to he considered.
Where regular flows of traffic already exist, such as retail deliveries from a local depot, the time factor—including allowance for modern traffic congestion—may well be the limiting factor on the number of consignments a driver can reasonably be expected to collect and/or deliver in a working day. In that event, whatever the theoretical economic advantages ot running a larger vehicle may be, it would be a fruitless exercise under modern traffic conditions.
Relative to the size of the load, the weight or number of consignments may not be the only determining factor. There are a number of traffics—for example, day-old chicks or certain types of food—where the operator's main problem is one of cubic capacity. In some instances the additional clear platform space afforded by the articulated vehicle is sufficient reason for its choice on this score alone.
Closely allied with the load factor is the average distance over which the vehicle is likely to operate. To some extent this may he conditioned by sales policy and the level of competitiveness existing in particular trades and industries. Where over many years customers, by the very standard of service traditionally provided, have been conditioned to accept, say, a twice-weekly delivery any change in such a standard would he difficult to introduce. Despite transport economics, in isolation. proving otherwise it might be commercially advantageous overall to continue to provide such a service. In that event selection of the best vehicle for the job would have been determined largely by factors outside the sphere of purely transport operation.
The accommodation of special types of traffic is largely met by appropriate types of bodywork although, on occasions, lowloading chassis may also be hecessary for the basis for such bodywork.
Wages and Design Because the driver's wages form such a high proportion of the total cost of operating a commercial vehicle it is obviously a worthwhile proposition to explore every possibility of increasing a driver's efficiency by improved vehicle design.
Although not directly included in the statutory requirements, wages paid to C-licence drivers tend to be similar to those of Aand B-licence drivers. Moreover, because many C-licence drivers are engaged on retail deliveries, it is necessary for them to get in and out of their cabs many times during a working day. Consequently, a relatively modest improvement in cab and vehicle access could prove a worthwhile proposition and fully justify any additional outlay thereby made necessary.
Despite considerable modernization of industry in post-war years, there are still a large number of old premises to which hauliers have to deliver which have limited access by way of width or headroom, or both. Particularly does this apply in agriculture and allied basic food processing, where by their very essential nature many of the companies so engaged are long established and for whom any policy of modernization must be a long-term project. Here again, and regardless of any additional capacity or dimension made possible by future Construction and Use Regulations, the physical limitations of the premises to which the operator has to collect and deliver must determine the size of vehicle.
Height Problems The respective heights of loading banks and platforms of goods vehicles are obviously of concern to an operator when selecting a new vehicle. But even in the simplest case, when a C-licence operator is delivering a standard product between two points directly under his control, it is seldom possible to arrange for the height to be precisely the same (and so facilitate to the maximum loading and unloading), because of the variation in platform height'as a vehicle is being unloaded, and also subsequent variations between new and older vehicles. In practice, therefore, it is often necessary to devise some form of connecting platform between the loading bank and the vehicle in cases where goods are being loaded on to the vehicle by trolley.
That being so, even in near ideal circumstances the problems of the general haulier arc obviously much greater when endeavouring to match the platform height of his vehicles with the many loading banks at which he will have to collect and deliver goods. As with many other of his problems the solution will he only partial—namely, a compromise which in practice is found to be around 3 ft. 8 in. for the average platform height of a general purpose vehicle.
More specialized conditions to be taken into consideration when selecting a new vehicle are the height of bridges and any other overhead restrictions in the operator's locality and, where appropriate, maximum loading limits for such bridges. Whilst the continued development of the modern commercial vehicle has removed the hazard of exceptional gradients on
main roads as one of the operator's more serious problems, nevertheless the right selection of whatever alternatives are available to form the most suitable combination of engine, gear ratio, actual ratios and tyre specification will ensure the most economical performance within the prevailing circumstances. Whilst correct selection of gear ratios will give as wide a range of vehicle performance as possible, special operating conditions may require additional consideration. Despite the advantages which can readily be quantified as a result of loading on both the outward and return journeys, there will continue to be types of operations evolving a fair proportion of light or empty running. Here again this is in contrast to the comparable problems of a p.s.v. operator, when the extremes between a fully loaded and an empty bus are slight compared with the corresponding conditions that could apply with a goods vehicle. In such circumstances the much wider range of performance offered by the two-speed axle could prove a worth-while additional initial outlay.
Just as a transport service as a whole can be considered as a link in the chain of manufacture and sales, so the selection of a vehicle is inter-related with transport policy as a whole. In this context the problem as to whether a rigid or articulated vehicle should be chosen is dependent on a wider range of circumstances than would normally apply in the choice between one type of rigid vehicle and another. Incidentally, the term "articulated vehicle" implies that it is intended to exploit the principle of articulation, i.e., with semi-trailers, as distinct from looking upon an articulated vehicle as just another complete entity. The economics of using articulation to the full was discussed in this series on September 6, when it was shown that by the use of two semi-trailers (i.e., one spare trailer) and one tractor unit, a saving of 8-61 per cent could be effected as compared with one tractor and one semi-trailer only. With two spare trailers the saving rose to 18.54 per cent. Other factors to be considered when selecting a commercial vehicle will be discussed next week.