A dragline this size has no wheels at all.
It rests on a round steel tub, and it moves by lifting part of its own weight onto two shoes, shifting, and setting itself back down.
One cycle covers a few feet. Then it does the whole thing again.
Which is fine when the next cut is next door.
It is not fine when the coal sits on the far side of the lease with a working rail line in between.
So somebody put the machine on tires.
Stepping moves weight, rolling only carries it
Walking is not driving. Nothing on a dragline turns against the ground.
The machine lifts, leans, sets down and repeats, and every stage of that sequence is a full load transfer through hydraulics and steel.
So the speed limit is not power. It is cycle time.
Add up enough cycles and the machine covers roughly six tenths of a mile in twelve hours, working without a break.
A wheel inverts that. The load transfers once, at the start, and after that the weight simply rides.
Everything the engine does goes into forward motion rather than into picking itself up.
That is the whole trade, and it moves the hard question off the machine and onto the ground underneath it.
The machine and the hole it works in
This one is an older American built dragline with a boom 325 feet long, the kind that throws a bucket out over a pit and drags it back full of overburden.
Working weight runs about 6.8 million pounds, near enough 3,400 tons.
It sits on a coal lease in central Queensland, in the Bowen Basin, where pits run for miles and the dirt on top has to come off before anything below is worth touching.
The coal it was needed for lay in the southern pits.
Between the machine and that coal ran an export rail corridor carrying loaded trains from several mines out to the coast.
Nobody was going to close that for a month.
Eight towers, 560 tires and a fixed shutdown
Hydraulic jacking towers went in underneath and raised the entire machine about 8.2 feet clear of the floor.
Older practice in Australia used climbing jacks, lifted in stages on stacks of timber packed by hand. The towers used here take steel cassettes at the base instead, so a crew feeds the lift rather than building it.
The load then came down onto five groups of transporter modules, 28 axle lines apiece, riding on 560 tires.
Spread that thin, ground pressure stayed under roughly 1,840 pounds per square foot, and steel mats went down wherever the floor was soft.
The run covered 16.7 miles in ten days, averaging close to five miles a day on transporters rated to three miles an hour.
The rail crossing was the fixed point. A temporary ramp had to be built, used and removed inside a 72 hour shutdown taken in August of 2025.
The branch manager on the job gave the reason without decoration: competing work in the area meant the next available window would not have come around for another three months.
What the record covers and what it leaves out
The claim here is about pace, not size.
A fully assembled dragline had already been rolled across Queensland once before, in 2013, and that trip ran close to 62 miles between two mines, more than three times this distance.
What is new is ten days and five miles a day, at this weight, with a live rail corridor sitting in the middle of the route.
There is also no referee. Heavy transport records get announced by the contractors that set them, and nobody independent audits the distance or the clock.
The method has hard edges too. It wants a floor that will take the pressure, a route that can be graded, and a structure willing to be picked up whole, which rules out plenty of machines, including the one cut into 27 separate loads and hauled by road across Texas, or the single lifts that go to the largest crawler cranes.
The limit moved off the machine
A dragline that is not digging is not a slow asset. It is a stopped one.
These machines strip the overburden that every truck and shovel behind them depends on, so a month of walking is a month the pit does not advance.
That is the arithmetic that pays for 560 tires and a fleet of jacks.
What has changed is where the binding constraint sits. It is no longer the gait of the machine, as the contractor’s account of the move sets out.
It is ground conditions and a rail timetable, and both of those are somebody’s schedule rather than a law of physics, as trade coverage of the job recorded.
Schedules can be argued with.
The jacking towers turned out to be the cheap part.
