Scale Ticket Shows One Trailer Overloaded
At a scale on I-295, your 80,000-pound doubles set yields: steer axle 11,400 lb, drive tandem 33,800 lb, lead trailer axle group 16,700 lb, rear trailer axle group 18,100 lb. The steer limit is 12,000 lb, drive tandem 34,000 lb, and each trailer axle group is rated 17,500 lb. Gross limit is 80,000 lb. The only movable cargo is a 1,500-lb pallet of bagged seed in the rear trailer; the lead trailer has 18 inches of open floor space at the nose. The rest of the cargo is 12,000 lb of bagged seed on pallets, and you have four 2-inch web straps with working load limit 5,000 lb each. The scale officer is waiting for your ticket, and the nearest certified scale is 6 miles away.
1. Identify every legal weight problem and calculate how much weight must move and to where. Is moving the whole 1,500-lb pallet acceptable?
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The rear trailer axle group is the problem: 18,100 − 17,500 = 600 lb over. Gross is exactly 80,000, so I cannot add weight; I must redistribute it. The lead trailer has 17,500 − 16,700 = 800 lb of capacity, so moving 600 lb from the rear trailer to the lead trailer would bring the rear to 17,500 and the lead to 17,300. The steer and drive are under their limits by 600 and 200 lb.
Moving the whole 1,500-lb pallet is not acceptable: the lead trailer would go to 18,200 lb, 700 lb over its 17,500 rating. Also, placing it at the nose could add weight to the drive tandem, which has only 200 lb of margin. I would break the pallet down or move only 600 lb, place it over the lead trailer’s axles rather than at the nose, and re-scale.
2. How should you secure the 12,000-pound seed load after redistribution, and does your current tiedown arrangement meet the minimum?
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The 12,000-lb seed load needs aggregate tiedown WLL of at least 50% of the cargo weight, or 6,000 lb. Four 2-inch web straps at 5,000 lb WLL each give 20,000 lb aggregate, which exceeds 6,000 lb. The minimum number of tiedowns for an article over 10,000 lb is four, so four straps meet the count if each is properly attached to the trailer and the cargo. After moving 600 lb, I would re-check that every pallet is restrained, straps are tight and not cut by edges, and the load cannot slide forward into the dolly or backward into the doors.
3. What would you do if re-scaling shows the drive tandem at 34,200 lb after you move the load?
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If the drive tandem re-scales at 34,200 lb, it is 200 lb over. I would not leave the scale. That means the 600 lb I moved forward added too much to the tractor, likely because I placed it at the nose of the lead trailer. I would move that load rearward within the lead trailer-over its axles-or redistribute within the rear trailer so the rear trailer is not over and the drive is not over. Then re-scale all axle groups. If I cannot get all groups legal at the nearest certified scale, I would offload or rearrange cargo before moving.