Tridem anyone? I must check out my memory stick more often as this little gem has been sitting on it for at least a week. No doubt that Towering Titan of Truck Tittle-Tattle will be wondering why I haven't blogged it. Anyroadup Biglorryblog can confidently announce Volvo Trucks is offering customers a newly-expanded range of air-suspended bogie variants and front axles offering better manoeuvrability and greater comfort for rear-end heavy tippers, mixers, tankers, crane applications and roll-off skip-loaders---and it includes this tridem set up above. Ahhh... I hear you say 'Is it a tridem... Or a tri-drive?"
Answer: It's a tridem and here it is from the front with a rather attractive blond lady driver in the cab (but I digress, in a clearly politically-incorrect sort of way). In fact it's no ordinary tridem. "This is a Volvo 8x4 Tridem - a factory-fitted three-axle bogie with air suspension and a steered tag axle" and the people from Gothenburg go on to tell me: "With three axles and a short rear overhang, the result is good stability and excellent grip even in difficult road conditions. A steered tag axle, in combination with a short wheelbase, also means the truck is particularly easy to manoeuvre." Now click through here for more...
"The trend is towards increasingly heavy loads, at the same time as demands on efficiency and comfort are increasing," Martin Palming, product manager for chassis development at Volvo Trucks tells me. "And by expanding the chassis range for the Volvo FH and Volvo FM, we are meeting our customers' requirements and giving them greater scope for a solution that is optimised for productive operations. With a wheelbase of 3.9 metres and a steered tag axle, the turning radius for a truck with a 32 tonne gross weight is no more than just 7.8 metres," explains Martin.
Whenever necessary, the tag axle can be raised to reduce friction with the road surface which naturally also reduces tyre wear and fuel consumption. Meanwhile, the Volvo Tridem 8x4 is ideal for mixers, tankers, bulk carriers, container transport and skip-loaders with bogie loads of up to 32 tonnes and gross weights of up to 42.5 tonnes. So it should have more than enough capacity for a UK eight-legger...
BLB - Just like to point out that the design front axle capacity is 9tonne and the rear bogie is 24tonne and not 32tonne as per your description. The overall GVW for a 4 axle vehicle is of course 32tonne. The chassis layout is more suitable for rear end heavy loads as you have described, mixer, tanker, skip, roll on off and recovery are all applications that spring to mind.
While having excellent manouvrability -In terms of weight distribution with only 9t at the front and 24t at the rear it does not necessarily favour tipper bodies, so care needs to be taken when specifying this body type.
Being air suspended any tipper application will require a full length subframe.
could you please explain why full length subframe is needed when on air, and would it be stable when tipping?