Tri-axle overload and steel coil securement
A 6x4 tractor with a tri-axle flatbed arrives at a weighbridge near Dammam. The plate shows a gross combination mass of 40,000 kg; the trailer bogie is rated at 24,000 kg and the drive axle at 13,000 kg. The load is three steel coils, 9,000 kg each, loaded with two coils at the rear of the deck and one at the front, resting directly on the steel deck. The rear coils are chocked with timber only at the rear and held with two chains over the top. The weighbridge ticket reads: steer axle 7,100 kg, drive axle 12,400 kg, trailer axles 27,600 kg. The loader says the last truck took the same load and was fine. The driver has a 300 km run and a delivery slot in four hours.
1. Calculate and interpret the weights. Which limits are exceeded, and what do those exceedances mean on the road?
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Total = 7,100 + 12,400 + 27,600 = 47,100 kg against a plated GCM of 40,000 kg: 7,100 kg over, about 18%. The trailer bogie is 27,600 kg against a 24,000 kg rating: 3,600 kg over, 15%. The steer and drive axles are under their plate figures, so the immediate problem is total mass and where it sits, not one individual axle rating.
Consequences: tyres and bogie suspension are over their rated load, brake heat and stopping distance increase, the centre of gravity is higher and roll stability is poorer, and the combination is unroadworthy and illegal. The weighbridge ticket is the evidence, so 'the last truck was fine' is irrelevant - the load must come off or be rearranged and reweighed before it moves. A 300 km run and a four-hour slot do not change the rating plate.
2. What must be done before the vehicle moves, and how should the coils be arranged and secured?
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The load has to come down and be rearranged so total mass is within 40,000 kg and each axle and bogie is within its rating - in practice, reduce or redistribute the coils and reweigh until the ticket is compliant.
Coils should sit in cradles or on timber dunnage, not directly on steel deck, with chocks hard against the coil at the front, rear and both sides. Arrange the eyes crosswise (transverse) so a coil cannot roll along the deck, keep the load inside the headboard, and spread the weight so the bogie is not overloaded.
For securement, a minimum of four chains and load binders per coil, with edge protectors, tensioned evenly, and rechecked after 10-20 km. Chains over a bare round top can loosen as the coil settles or rolls against the chock, which is why proper chocking and direct contact matter more than the number of chains alone.
3. The loader says the previous truck was fine and the driver is asked to sign for the load. What is the driver's responsibility here?
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Signing the load document is the driver accepting that the load and weights are as described, so signing a 47,100 kg ticket makes the driver part of the violation. His duty is to the vehicle's rating plate and the weighbridge result, not to the loader's memory of another truck.
The practical route: refuse to sign, ask for the load to be rearranged, and insist on a second weighbridge ticket showing every axle within rating before departure. Record the first ticket and the conversation with dispatch. If the customer's slot is missed, that is a commercial problem, not a reason to run overloaded. If he signs and is stopped or crashes, the ticket is documentary evidence against him, and insurance may decline the claim.