Loading a 13.6 t Excavator on a Wet Lowbed
You must move your 13,600 kg tracked excavator 60 km on a provincial highway. The trailer is a tri-axle lowbed with a 25,000 kg GVWR, a 6,500 kg tare, and a 3.0 m wide, 8.5 m long deck. The deck was pressure-washed yesterday, but the ramps still carry about 20 mm of wet clay. In the toolbox are four 3/8 in Grade 70 chains with ratchet binders. One binder's handle is bent so it will not snap over centre, and one chain has a gouged link within 300 mm of the hook. The only tie-down points are four factory D-rings at the deck corners. The loading area is level gravel, but a 25 kV distribution line crosses the approach at roughly 8 m above grade. The machine is 3.1 m wide with a 2.9 m track length, and the boom must be lowered with the bucket curled for travel.
1. Work out the minimum securement requirement and decide what you will and will not use from the toolbox.
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Two separate tests apply: number of tie-downs and aggregate working load limit.
- Number. A machine well over 4,536 kg (10,000 lb) needs a minimum of four tiedowns under NSC Standard 10.
- Aggregate WLL. It must be at least 50% of the cargo weight: 13,600 × 0.5 = 6,800 kg. Four 3/8 in Grade 70 chains at roughly 2,990 kg WLL each give 11,960 kg, so the count and the aggregate WLL are satisfied on paper.
- Payload. 25,000 kg GVWR minus 6,500 kg tare = 18,500 kg capacity against 13,600 kg plus bucket and any attachments - acceptable, but the load must sit over the trailer axles.
The hardware itself fails. A gouged link near the hook is in the load-bearing zone and cannot be assessed by eye, so that chain comes out of service. A bent binder handle that will not snap fully over centre can creep open under vibration, so it is replaced, not 'made to work'. Four good chains and four good binders, or the machine does not move.
2. Describe how you actually load it, given the wet clay on the ramps and the overhead line.
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Sequence matters more than speed here.
- Clean the ramps and deck - wet clay is the most common cause of a track sliding off a ramp. Scrape, then grit or dry sand if needed.
- Position the trailer on level ground, wheels chocked, ramps aligned square and at the shallowest practical angle. Ramp angle drives track slip and the machine's tendency to nose over.
- Confirm the powerline approach limit for 25 kV in your jurisdiction before raising anything; keep the boom and stick low and load from the side away from the line. If the approach distance cannot be maintained, the utility is called to de-energize or the loading spot changes.
- Use a spotter who stays visible and outside the machine's swing.
- Climb in low gear, in a straight line, bucket low and curled, no turning or steering correction on the ramps. Turning on a ramp is how machines walk off the side.
- Park centred over the trailer axles, slightly forward for tongue weight, bucket lowered to the deck, house lock pin engaged, blade or bucket contacting the deck.
3. What does your pre-departure inspection cover before the truck leaves, and what paperwork does a 3.1 m wide machine trigger?
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Walk the load, not just the chains.
- Chain geometry. Four chains, each pulling down and slightly forward or back, at a shallow angle, in direct tension with no side load on the binder. Binder handles fully over centre and secured with wire.
- Contact and protection. Chains must not run over sharp edges or through the bucket teeth; edge protectors or a different routing. Nothing loose on the deck.
- Machine configuration. Bucket curled and resting on the deck, boom lowered, house lock pin in, attachment pins checked, no hydraulic creep that would slacken a chain.
- Trailer. D-ring welds and deck for cracks, tyres, lights, brakes, ramp stowed and pinned.
- Re-check after 5–10 km. Chains settle; the first stop is where a loose binder is caught.
Paperwork: at 3.1 m the load exceeds the usual 2.6 m legal width, so it needs an oversize permit, signage and flags or lights as the permit specifies, a route check for restrictions, and the driver's load securement responsibility confirmed.