Don-Bur has finished building 25 straight-frame box van 15.65m Longer Semi-Trailers (LST’s) for a parcel courier, including an industry-first “wedge” shape with a full-length Lifting Deck. The 4.88m high tri-axle parcel-carriers have a volume increase of 16.7m3 when compared to their standard length counterparts and, as a result of the increased capacity, deliveries can be cut by 1 in every 6.4 legs; directly saving 15.6% in fuel and proportional CO2 emissions.
Operated under VSO (Vehicle Special Order), the 123.7m3 mega-volume trailers will support the main trunking operation.
When docking, the global operator uses conveyor loading arms which extend into the rear of the trailers, where loose load is manually packed from front to back to gain maximum space utilisation. Normally, a step-frame would have been the obvious choice for optimal cubic capacity but the client wanted two maximum length straight platforms for ease of loading on both decks.
The solution was a “wedge” shaped trailer with a tapered straight-frame chassis running from a standard fifth wheel height down to a rear deck height of just 1.18m (on standard 22.5” super single tyres). They also sport a super-thin “mega” neck which generates 2.13m height under the lifting deck platform; ideal for personnel access. To boost volume still further, Don-Bur’s lightweight “Blade” panels were specified which, at just 7.5mm thick, generate an additional 1.1m3 cube.
The 14.45m long Lifting Deck itself is only 55mm thick and is rated at 10 tonnes. In addition, it is the first of its type to come fitted with weight sensors to eliminate overloading on the top deck which will help to reduce the risk over roll-over.
The demanding specification would have been a challenge under any circumstances but these LST’s were also fitted with a Tridec, mechanical positive-steer rear axle which provides better manoeuvrability than standard fixed axles.
The EcoStream aerodynamic curved front roof section provides the final finishing touch, offering up to 18% fuel saving in comparison to flat-roof double decks.
Written by: Richard Owens
Published by: Don-Bur