CARRYING OPI
Page 76
Page 77
If you've noticed an error in this article please click here to report it so we can fix it.
• Close co-operation between vehicle operators and equipment manufacturers is probably more in evidence in the car and truck delivery sector of road transport than in any other. Some recent innovations in design of the highly specialised semi-trailers and trailers used for carrying trucks and cars have led to significant improvements in operational efficiency. However, the objective of the engineers at the delivery companies and their suppliers has been not simply to step up the carrying capacity of their trailers, but also to enable them more easily to accept a wide mix of vehicle types and to make them even safer.
Abbey Hill Vehicle Services of Yeovil, Somerset, claims to be this country's largest vehicle delivery company. It has recently taken delivery of its first batch of three-deck, tri-axle semi-trailer transporters, each of whicl can carry up to 12 cars. Formerly Abbey Hill's maximum capacity was 10 cars on articulated vehicles, 11 on drawbars. The new transporters were developed jointly by Abbey Hill's own engineers and those of the supplier, Hoynor of Braintree, Essex.
A key factor in the increased capacit of the Hoynor semi-trailer (typical max urn loads are nine Vauxhall Cavaliers, x Range Rovers, five 200 and 300 -ierpa vans, or 11 Ford Fiestas) is its iassis and suspension configuration. Dr many years Hoynor has employed a nimeter frame over most of the ngth of its transporter semi-trailer, it now the conventional chassis frame is been eliminated, even in the area the bogies suspension.
The truck-carrying version of the
semi-trailer is believed to be tique in its ability to carry three 6x 4 active units. Vehicles of this size are wide as the trailer carrying them, so hydraulic mechanism is required to le shift the rear pillars during loading. multaneous motion of the top and botm of each pillar is achieved by the e of a specially-selected four-way diier valve in the hydraulic circuit. Rubery Owen-Rockwell Neway air spension has been specified for the mi-trailer to give the lowest ride ight commensurate with the supple ringing required to protect the load, A winch is built into the superstruc:-e of the commercial vehicle version the transporter to overcome the Dblem of wheelspin during drive-on ding. Anti-skid surfaces are used on surfaces where drivers walk.
Another move to improve operational safety is the abandonment of lead screws in favour of an hydraulic rani and chain system, similar to a fork-lift truck mast mechanism, for raising and lowering the platforms. The ram pillars stand 4.17m high on the coupled semitrailer and incorporate fabricated racks with which a pneumatically-operated pawl engages. Hoynor says that the decks cannot fall, even in the event of mechanical failure.
Abbey Hill's policy is to use mainly lveco tractive units, but the latest prime mover for its three deck drawbar transporter is a Leyland Roadtrain 17,28, modified by Leyland's own special vehicle engineering division.
The 5.4m wheelbase Roadtrain is fitted with low profile tyres which help to keep its chassis frame height as low as 940 mm.
Charles Roberts Engineering has been in the business for about 120 years and is now well-established as a leading tanker manufacturer. However, the company's move into vehicle transporter manufacturing is a recent one, made through a licensing agreement with Kassbohrer of Germany.
At a recent display at Hartford Motors, near Abingdon, Oxfordshire, Charles Roberts joined forces with Kassbohrer, Leyland Trucks and Drum Engineering to demonstrate its latest drawbar and semi-trailer transporters and the high speed loading and unloading techniques that can be used with them. BRM (Butterfield Roberts and Murfitt) Kassbohrer transporters use Kassbohrer's own air suspension. To • raise and lower upper decks, hydraulic, spindle screw and pneumatically operated locks arp