thirtle26 Posted April 26, 2016 Share Posted April 26, 2016 I have just been to my local weighbridge with my Burstner Ixeo. The front axle was weighed. The total van was weighed and the rear axle was weighed. The weights were front 1520 kgs, rear 1900 kgs and the total 3520 kgs. adding the front and rear axle weights together gives a combined weight of 3420 kgs. A difference from the total weight of 100 kgs. I would have expected the difference to be less than 100 kgs. Am I missing something? Link to comment Share on other sites More sharing options...
Steve Drew Posted April 26, 2016 Share Posted April 26, 2016 It probably depends on where you stop while weighing the front and back axles, just had mine done and adding the 2 axle weights together is exactly the same as the gross weight. Link to comment Share on other sites More sharing options...
Tracker Posted April 26, 2016 Share Posted April 26, 2016 It's best to position the van so the axle being weighed is as close to the centre of the weighbridge as you can get it without having both axles on. This helps to reduce any leverage effect and so aids mental bliss! Link to comment Share on other sites More sharing options...
Deneb Posted April 26, 2016 Share Posted April 26, 2016 There could be a number of reasons. All weighbridges operate within certain tolerances. They may only register increases every 20kg for instance. Dynamic axle weighing, where the vehicle is driven slowly over a narrow plate, has greater tolerances than a conventional weighbridge. A bridge calibrated to be accurate at 30 - 40 tonne may be less so at relatively lower weights. If it was a static weighbridge, with a large plate that you drive the vehicle on to, where did you place each axle when measuring the axle weights? Were they as far towards the centre of the weighing plate as possible (so that the axle not being weighed was as close to the edge of the plate as possible without being on it) or was the axle being weighed positions so that it was only just on the plate? If the latter, was the run-up to the plate level, inclined up or downwards? When you carried out the gross weighing, did you position your vehicle on the centre of the plate, or just on it at one end? If not a dynamic axle weighbridge, was each weight obtained with the engine switched off and the brakes released? All of these things can have an effect on the weights obtained. I used to carry out enforcement weighing in a previous life. If the tolerance of the bridge was plus or minus 20kg for example, I would want to see the gross weight being within 40kgs of the sum of the axle weights, otherwise it would suggest that either the weighing was carried out incorrectly or the calibration of the bridge was suspect. Tolerances can be as much as plus or minus 100kgs for a single axle weight on some bridges though, with an accepted gross weight tolerance of plus or minus 100kgs multiplied by the number of axles. Not a great deal when weighting a 38 - 40 tonne truck, but the possibility of a much greater discrepancy on a 3.5 tonne van. Link to comment Share on other sites More sharing options...
thirtle26 Posted April 26, 2016 Author Share Posted April 26, 2016 Thanks Deneb I am going to a different weighbridge as the one I went to had a slope upto and going from it. I will also follow your advice about axle placement. I'll let you know what happens. Link to comment Share on other sites More sharing options...
Steve928 Posted April 26, 2016 Share Posted April 26, 2016 The total weight taken with both axles on the platform will be the accurate figure as any small change in level off the edges of the plate will affect the single axle readings. I've had a couple of weighings where the sum of the 2 axles equals the total but I suspect that was down more to the operative 'adjusting' the axle figures to fit the total than anything else.. Link to comment Share on other sites More sharing options...
Deneb Posted April 26, 2016 Share Posted April 26, 2016 thirtle26 - 2016-04-26 4:17 PM Thanks Deneb I am going to a different weighbridge as the one I went to had a slope upto and going from it. I will also follow your advice about axle placement. I'll let you know what happens. If the approach sloped down from the plate and your other axle was a little way from the plate, that will almost certainly be much of the reason, since by being on a slope you are transferring weight downhill, off the axle that is sitting on the plate and loading the other axle. We were taught when weighing a 2-axle vehicle to always place the tyres of the axle not being weighed onto the metal frame surrounding the weighbridge plate, ensuring that no part of the tyres was actually touching the plate. That might be a little extreme for your purposes though, particularly if you don't have an assistant to act as a guide and maybe a line of frustrated truck drivers all queuing up behind you! Link to comment Share on other sites More sharing options...
Brian Kirby Posted April 26, 2016 Share Posted April 26, 2016 Wrong button!! Link to comment Share on other sites More sharing options...
Brian Kirby Posted April 27, 2016 Share Posted April 27, 2016 Take the van to the weighbridge and tell the operator you want the actual laden weight plus both axles. You should then be instructed to drive across the plate so that the front wheels are just off it. That will give the rear axle load (A). Then to reverse back to as close to the centre of the plate as possible. That will give the actual laden weight (B). That should be all, as the machine should then calculate B - A to give C, the front axle weight. There should then be no confusion. It is the same calculation as used for a collection of bulk goods (gravel, builder's sand, etc). Weight the empty truck (A). Then weigh the loaded truck (B). The load © is then B-A, which in that case would be used to calculate the cost. Link to comment Share on other sites More sharing options...
lancepar Posted April 27, 2016 Share Posted April 27, 2016 Brian Kirby - 2016-04-27 9:27 PM Take the van to the weighbridge and tell the operator you want the actual laden weight plus both axles. You should then be instructed to drive across the plate so that the front wheels are just off it. That will give the rear axle load (A). Then to reverse back to as close to the centre of the plate as possible. That will give the actual laden weight (B). That should be all, as the machine should then calculate B - A to give C, the front axle weight. There should then be no confusion. It is the same calculation as used for a collection of bulk goods (gravel, builder's sand, etc). Weight the empty truck (A). Then weigh the loaded truck (B). The load © is then B-A, which in that case would be used to calculate the cost. Ditto Brian, but I think the the weighbridge needs to be sunk in for this to be accurate, a lot of new weighbridges are above ground and have a slope up and a slope down which means the vehicle will not be level. Will the method still be accurate enough in that case? B-) Link to comment Share on other sites More sharing options...
Malo37 Posted April 27, 2016 Share Posted April 27, 2016 Maybe you were hit by a gravitational wave. Link to comment Share on other sites More sharing options...
thirtle26 Posted April 29, 2016 Author Share Posted April 29, 2016 Tried another weighbridge. The rear axle was 1840 kg, the front axle was 1540 kgs and the total was 3450 kgs. Still a difference of 70 kg between the individual axle weights and the total. As the maximum weghts are rear 2000 kg, front 1850 kg and total 3700 kg I am not too worried. Link to comment Share on other sites More sharing options...
Billggski Posted April 29, 2016 Share Posted April 29, 2016 Just be careful when fully loaded for travel, as most of the weight added goes on the rear axle. Link to comment Share on other sites More sharing options...
snowie Posted April 30, 2016 Share Posted April 30, 2016 I had a similar problem the last time I had the van weighed; a ramped weighbridge. The "flush" one I had the van weighed on first time,was no longer available, (chicken farm gone out of business) so no choice. I'm looking for a "flush" one in the Lincoln/Newark areas; any suggestions welcome, regards alan b Link to comment Share on other sites More sharing options...
snowie Posted May 13, 2016 Share Posted May 13, 2016 snowie - 2016-04-30 11:10 AM I had a similar problem the last time I had the van weighed; a ramped weighbridge. The "flush" one I had the van weighed on first time,was no longer available, (chicken farm gone out of business) so no choice. I'm looking for a "flush" one in the Lincoln/Newark areas; any suggestions welcome, regards alan b Well I found one that I'm very happy with, and I got individual wheel loadings, which was very informative. If anyone is looking similarly in this area pm me and I'll pass on the details, rather than broadcast to the nation. regards alan b Link to comment Share on other sites More sharing options...
(275x206)(250x187)(200x150)(175x131)(150x112).thumb.jpg.c24933294f12c892742dc8c0944d6117.jpg)
Recommended Posts
Archived
This topic is now archived and is closed to further replies.