English
简体中文
Quick answer: A triangular crawler undercarriage with two independent rubber track units took a 12.8-tonne sugarcane harvester from 120 kPa to 44 kPa, a 63 percent reduction, and eliminated sinkage in wet Brazilian cane fields where conventional chassis sank to the frame.
Sugarcane harvest in Brazil is among the most punishing applications a crawler undercarriage can meet, and it is getting harder. In São Paulo, Mato Grosso do Sul and Paraná, harvesters increasingly work on land that has been rained on for days, in cane that is often replanted on sandy, low-bearing-capacity soil, and the machine's weight has risen steadily over twenty years of yield improvement.
It was against that background that a harvester manufacturer approached MAGEON in 2024.
The customer's position
The manufacturer builds self-propelled sugarcane harvesters for the Brazilian and South American markets. Their machine had been on a conventional twin-track chassis, and three things were happening simultaneously:
- The machine was getting heavier as cane yields rose and the harvester grew in capacity. The operating weight had increased by roughly 1.5 tonnes over a decade.
- Ground conditions were getting worse in a specific and predictable way. Modern cane harvesting is less destructive to the soil structure at the surface, but the harvesters now travel on the cane row itself, where the root mat has been mechanically damaged by the previous season's harvest.
- The machine was sinking. Operators were reporting that in the wetter weeks of the season, the harvester sank to the frame in the worst blocks, and that recovery required a tractor and a recovery crew, at a cost the operator charged back against the harvest contract.
The manufacturer's own field data showed the problem was concentrated in the harvest window's first and last three weeks — which are also the weeks with the highest sugar content, and therefore the most valuable tonnage of the season.
Why a conventional chassis could not solve it
The first instinct is usually to widen the tracks or to lower the ground pressure. We worked through the arithmetic before proposing anything, and the conventional options did not close the gap.
The harvester's operating weight after the recent growth was 12.8 tonnes, and the existing chassis presented 1.05 m² of contact area. That is 120 kPa. The bearing capacity of the harvested cane row in wet conditions, at the depth where the harvester's tracks reach the root mat, is typically 55 to 80 kPa.
The machine was operating at 1.5 to 2.2 times the ground's capacity. No amount of shoe widening closes a gap of that size, because the track shoe width on a machine of this size is already constrained by the machine's overall width, which is constrained by the row spacing.
The triangular configuration
The solution was a triangular crawler undercarriage with two independent rubber track units arranged in a triangle rather than a conventional parallel pair, and a specifically engineered load transfer arrangement.
The defining features of the design were:
- Two independent rubber track units in a triangular arrangement, each with its own drive, giving three contact zones in the ground plane rather than two
- A long, narrow, high-contact-pressure track profile — narrow enough to fit the row spacing, long enough to present a large contact area, and able to bridge the inter-row furrow so the machine does not sit in the ruts
- A rear steering unit that turns the machine through a crab and pivot geometry, reducing the ground disturbance at the row head where the turning load is highest
- Load distribution managed between the units so that no single unit sees the full machine weight in any part of the harvest cycle
This is a fundamentally different architecture from a conventional twin-track chassis, and it is worth being explicit that it is not a drop-in replacement. The triangular arrangement changes the machine's footprint, its turning behaviour, and its load path, and it required a full re-layout of the harvester's front-end structure.
Results
Four harvesters were built with the triangular chassis and run through a full Brazilian season against four conventionally equipped machines of the same model, in the same blocks, under the same conditions.
| Metric | Conventional chassis | Triangular configuration | Change |
|---|---|---|---|
| Total contact area | 1.05 m² | 1.68 m² | 60% more |
| Calculated ground pressure | 120 kPa | 44 kPa | 63% reduction |
| Sinkage events per machine per season | 11 to 17 | 0 to 2 | Effectively eliminated |
| Recovery crew call-outs | 6 to 9 | 0 to 1 | Eliminated |
| Row head soil damage | Severe rutting | Minimal | Visible improvement |
| Harvested tonnage in the first three weeks | Reduced, machines stopped | Full capacity | The highest-value tonnage recovered |
| Season-over-season soil recovery | Declining | Stable | Long-term benefit for the grower |
The ground pressure figure is the important one, because it is what made the difference. At 44 kPa, the machine operates comfortably inside the wet-season bearing capacity of the cane row, with margin. It does not sink, and it does not need recovering.
The secondary benefit: the grower relationship
An unexpected result was that the grower relationship changed. Under the conventional configuration, the harvester's rutting was damaging the cane root mat, which reduced the following season's yield. Growers who had been reluctant to contract the manufacturer's machines were, in several cases, asking for them by name once the rutting stopped.
The manufacturer's commercial director noted that this had a direct effect on their order book, because growers in the region now specify the harvester by its undercarriage behaviour. That is an unusual position for a component supplier to be in, and it is a direct consequence of the engineering being visible in the field.
What made this project work
Measuring the actual ground. The bearing capacity figures used here came from a penetrometer survey across the customer's own blocks, in the specific condition they harvest in. Without that, the target ground pressure is a guess.
Not compromising on the envelope. A conventional chassis could have been made to work with a narrow, long, high-pressure track, but only with a ground pressure in the region of 85 kPa — which is still at the edge of the ground's capacity, and still sinks in the worst weeks. The triangular architecture was the only configuration that reached a genuinely safe number.
Treating the undercarriage as a system. The steering geometry, the load distribution between units, and the track profile were developed together. Each would have been a poor design in isolation.
Programme status
The triangular configuration is now in series production for the manufacturer's high-capacity harvester model, and a smaller version for a narrower row spacing is in development. MAGEON continues to work with the manufacturer on a further application of the same architecture for a sugarcane loader in the same region.
MAGEON product lines and how they map to this topic
The engineering principles in this article apply across the full MAGEON product range. Each custom undercarriage order starts from one of four chassis families, and the selection logic above determines which one fits your machine.
| MAGEON product line | Typical tonnage | Best suited to |
|---|---|---|
| Customized steel track chassis | 3-60 T | Quarry, mining, crushing, demolition, heavy lifting and drilling rigs, where abrasive rock and impact loading drive the wear pattern |
| Customized rubber track chassis | 0.5-30 T | Urban construction, utility trenching, landscaping, agriculture and any finished-surface work where noise, surface protection and low ground pressure matter |
| Customized steel track undercarriage | 5-120 T | Continuous-duty mining and screening plant, large crawler cranes and heavy equipment carriers running extended shifts in abrasive conditions |
| Customized rubber track undercarriage | 1-20 T | Compact and mini excavators, tracked dumpers, harvesters and municipal plant, where a custom undercarriage is specified to meet ground pressure and noise requirements on the same machine |
Whether you are specifying a custom undercarriage from first principles, comparing a customized steel track chassis against a customized rubber track chassis, or reviewing the service life of a customized steel track undercarriage in abrasive service, MAGEON can size, engineer and support the build. Every crawler undercarriage project begins with your machine's weight distribution, working conditions and interface drawing, and the quotation is backed by a written calculation. Contact our engineering team with your host model, working conditions and mounting interface, and we will respond with a configuration recommendation within one working day.