Thought combines couldn't get any bigger or heavier? Then think again, because the prototype Tribine combine on display at this week's Ag Connect Expo Show in Kansas City claims to be able to carry an astounding 27t in its grain tank.
It's not like any harvester you've ever seen before, either. Designed by Indiana farmer Ben Dillon over the past 15 years, it marries a more-or-less regular combine with a giant 27t chaser bin. That's more than double the 10.8t payload of the biggest combine tank on the UK market.
According to Kansas' High Plains Journal, the front half of the Tribine (including the cab) is essentially an Agco Gleaner S77 rotary combine with the grain tank removed and replaced with a 370hp engine. Clean grain passes from the front threshing module to the rear tank module via a 30cm diameter auger.
Chopped straw and chaff blasts out in the space between the two modules, helped by a powerful set of hydraulic fans.
Three hydraulic pumps power the Tribine's all-wheel drive, all-wheel steering and unloading auger. Because the machine is articulated and can turn 30deg to either side, (as well as being able to crab steer) the rear section can get somewhat closer to a trailer than is normal.
Overall length is 10.6m, less than some regular combines, says Tribine Industries, the firm working on the project.
Transport width is said to be 4.4m. OK for the USA, but somewhat on the wide side for UK roads.
Getting the corn into trailers or trucks certainly shouldn't take too long. A 56cm (22in) diameter, 7m (23ft) long two-section discharge auger, set at just less than 45deg right at the back of the machine, can empty at a rate of 13.5t/minute, allowing the whole 27t tank to be emptied in just over two minutes.
Reliably dry harvesting conditions in the USA mean unloading is normally straight into a truck parked on a road or farm track.
Extensive use of aluminium panels has kept overall weight down, but the whole unit when full weighs 45t, about the same as a big combine.
A set of huge 1.2m wide, 1.8m tall tyres is said to give less compaction than a standard combine's, let alone a 200hp tractor pulling a 27t chaser bin.
More testing will be done this summer, says Mr Dillon, and he is looking for a production partner.
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