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Row over air-dump scheme for tippers
Page 8
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• SAF's recommendation that operators using a tipping trailer equipped with its air-suspended running gear should dump the air from the suspension before raising the body has been slammed as "quite draconian".
John Ruffles, an HGV and trailer engineering consultant based in Bury St Edmunds, says: "Dumping air is not a satisfactory solution when discharging a load. When air dump takes place loads of up to 30,000kg can be imposed on the rearmost axle and suspension, which can result in damage to the axle and rear end of the chassis frame."
Ruffles adds that dumping air results in the discharge point 'being considerably lowered, which can cause problems with the load and part of the load being held back in the raised body."
His comments follow the publication of the "operating recommendation" issued by SAF's UK distributor IMS of Loughborough (CM 24-20 October) and the recent artic tipper stability tests conducted by aggregates giant Lafarge. "They'll have a terrific job relying on a driver to do it," Ruffles warns. "They won't want to get out of the cab to do it so consequently it won't be done."
However, the SAF recommendation has been welcomed by Andrew Smith, director of Newton Commercials, the UK importer for Stas Trailers.
Smith says he has also written to other axle manufacturers including HOP and Discos Systems Solutions requesting similar guidance on how to treat the air suspension on a trailer when tipping.