Why compaction in the mobile silo is crucial today!
High harvest yields, tight timeframes and increasing demands on forage quality are putting ever greater pressure on compaction in the mobile silo. Whereas in the past work was often carried out with smaller unloading volumes and more time, today large quantities of green fodder must be cleanly fed into the drive-in silo and compacted within a short time.
This is precisely where it becomes clear that silo compaction is more than just driving over it with heavy machinery. For the higher the unloading volumes, the more crucial a well-designed compaction system becomes – otherwise air pockets remain, which later lead to fermentation problems.
It is precisely at this point that the solution does not lie in additional weight, but in the coordinated interaction between the Silage spreader and the Silage roller: only when layer formation and surface pressure are consistently coordinated can a mobile silo safely accommodate large harvest volumes and compact them to remain permanently stable.
Layer thickness as the basis of all compaction
Before discussing roller weight or silage rollers, one fundamental factor must be right: the layer thickness. It determines whether the applied pressure can even penetrate to the required depth later on. Even the best compaction technology cannot overcome physical limits if the silage material is deposited too high or unevenly.
Freshly delivered grass or maize silage should therefore be spread evenly immediately after unloading. The aim is to create an even, as thin as possible layer across the entire silo area. The layer thickness should be around 25 cm prior to compaction. Only in this way can the pressure build up layer by layer during the subsequent compaction, consistently forcing air out of the forage.
This highlights the importance of the right technique. A silage spreader ensures a wide, even distribution of the material, whilst a silage dozer blade pushes the material forward in a controlled manner and brings it right up to the edges and walls. It is not just the spreading itself that is crucial, but the evenness of the entire surface. The formation of piles or varying layer heights inevitably leads to uneven compaction – with consequences that become apparent later in the drive-in silo.
A professional silage process therefore does not begin with rolling, but with the structured build-up of each individual layer.
Direct comparison: Silage roller vs. roller weight
A direct comparison clearly highlights the crucial difference between roller weight and silage rollers: when compacting with a tractor, the pressure is transmitted to the silage exclusively via the tyres. The tyres act as a kind of buffer – they transfer the pressure to the silage only via their contact patch. As a result, the pressure is distributed over a comparatively large contact area, meaning that only a limited portion actually reaches the silage in a concentrated form.
A silage roller operates on a different principle. Here, the ballast acts directly on the silage via solid iron rings. The pressure is thus applied more concentratedly into the silage layer and is not distributed across a flexible tyre surface. For drive-in silos, this means more intensive and even compaction, allowing the pressure to penetrate the individual layers of the silage more effectively.
The difference therefore lies less in the additional weight and more in the way the pressure is applied to the silage. Whilst tyres tend to distribute the load, the Silage roller ensures targeted and effective pressure application across the entire working width.
Area-wide compaction with the silage roller
Front and rear weights are regarded in many farms as a straightforward solution for increasing compaction in the drive-in silo. Technically, however, the effect remains limited to the tractor tyres: compaction occurs primarily where the tyre makes contact, whilst gaps and deeper layers are only affected indirectly. To achieve the most uniform silage density possible, overlapping tracks, repeated passes and a very disciplined driving strategy are required. A modern silage roller does not operate with point-load wheel pressure, but with controlled area-wide pressure. The weight is applied to the silage material across the entire working width – evenly, consistently and independently of individual tracks. It is precisely this difference that determines whether a silage field is compacted only superficially or built up structurally throughout. Here it becomes clear that only the coordinated interaction between the silage spreader and the Silage roller enables a truly consistent compaction system.
When compacting the silage with a silage roller, a homogeneous pressure mat is created. Air pockets are reduced not only beneath individual tyres but across the entire surface. The silage is compacted layer by layer, resulting in a stable silage body. The compaction intensity can be adjusted using water-filled roller bodies or additional weights.
Making optimum use of space in the drive-in silo
In practice, high harvest yields often meet with limited storage space. When large quantities of silage are delivered in a short time, the quality of compaction determines how efficiently the available volume in the drive-in silo can be utilised.
The combination of even distribution and extensive silo rolling with the silage roller packs the material more densely. This means: more dry matter per m³ and more space in the drive-in silo.
Feedback from the field shows that a well-coordinated silage team allows significantly more loader wagons to be accommodated in the same silo.
With rising yields and limited building space, the question of available space for silage storage is becoming increasingly relevant. A high-performance silage roller helps to make optimum use of the existing space.
– Florian Huber-Stiegler, farmer from Styria
If, for example, 42 loads can suddenly be stored cleanly and stably instead of 34, that makes a noticeable difference – both in terms of feed reserves and profitability.
Three positive effects of using a Silage roller
Efficiency: passes, time and diesel
Every minute counts, especially during harvest time. If you work with a simple concrete or roller weight, the effective compaction performance is lower. Consequently, significantly more passes are required to achieve sufficient silo density. Every additional pass means higher diesel consumption, more machine hours and greater wear and tear – in other words, increased use of resources.
If, on the other hand, a silage roller compacts the silo evenly and effectively, the number of passes required is noticeably reduced. This saves not only diesel, but also time and mechanical strain on the tractor.
This makes work in the drive-in silo run more smoothly and efficiently. The drive-in silo compactor adapts to the speed of the forage harvester and transport – particularly important when large quantities are being brought in within a short time.
Safety at the silo wall: targeted compaction of edge areas
Edge compaction in a drive-in silo is particularly problematic when working with simple concrete or roller weights. To compact the edge zones sufficiently, the tractor must be manoeuvred very close to the silo edge. This often results in wear on the tractor tyres due to direct contact with the silo wall – a manoeuvre that is both technically demanding and safety-critical. The situation becomes particularly critical when the silage pile already protrudes beyond the silo walls. Driving too close can cause the machine to end up in an unstable position.
A silage roller with 500 mm side shift, on the other hand, allows compaction to be carried out precisely right up to the wall without the tractor itself having to be manoeuvred dangerously close to the silo edge. In combination with an integrated edge compactor, edge areas are actively and precisely compacted. This not only improves the quality of compaction at the edge but also enhances workplace safety – particularly with tall silo stacks or when the material is piled up beyond the wall.
Feed quality: fermentation stability, post-heating, losses
Anyone wishing to compact a silo is ultimately pursuing an important goal: maximum feed quality. Any remaining air pockets are a potential disruptive factor in the fermentation process. Comprehensive compaction using the silage roller reduces the risk of unwanted post-heating and creates stable conditions for clean lactic acid fermentation.
The result is evident at the cut: less post-fermentation heating, fewer fermentation faults and a uniform structure across the entire height of the silo stack. For the farm, this means more usable energy in the forage, more consistent performance in the barn and lower losses throughout the feed chain all year round.
Compaction thought through to the very end
Due to its design, a simple concrete or roller weight reaches its limits when compacting a mobile silo. The transferable pressure is limited by the tyres, edge areas are only accessible to a limited extent, and as unloading volumes increase, the number of passes required rises significantly. The desired compaction effect can therefore often not be achieved to the extent required for permanently stable silage.
This is precisely where a silage roller comes in. Thanks to the significantly higher surface pressure via the iron rings, the even pressure distribution and the targeted edge compaction, a homogeneous, dense silage body is created across the entire surface. In combination with a clean layer structure achieved using a Silage spreader or a silage dozer blade, the silo is systematically compacted.
The result: better use of space in the drive-in silo, lower losses and a more efficient process during harvest. It is not just the additional weight that is crucial, but rather the actual compaction effect within the silo.
More about MAMMUT’s compaction technology
Maximum roller weight up to 3,660 kg
Hydraulically adjustable frame
