Load and transport of bales: efficiency and safety

Whether tied or wrapped, round or square, hay or straw bales must be transported with properly equipped wagons to ensure the efficiency and safety of the operation. Manufacturers have developed solutions that can efficiently carry out the loading and positioning of the bales on the wagon and transport them in optimum conditions

 

Wrapped or tied with twine or netting. The round bales (but also large square bales) are ready and packaged artfully in the middle of the field. Job done? Certainly not! Because they need to be loaded and transported to the farm centre, where they will be stored carefully in dedicated buildings (or areas).

What can be used for loading, transporting and subsequent unloading? A common trailer or a simple flatbed wagon? Not quite, because modern technology has long made available specific machines, bale loaders, apparently simple equipment incorporating original and ingenious mechanisms to make the work fast and safe. The handling of bales seems a small matter, but we must not forget that we need to move very large objects (up to 1.8 m in diameter for round bales) and several hundred kg of mass (up to 1300 kg and above for big wrapped bales). These are operations which, especially in the unloading and storage phase, cause serious accidents every year in Italy, unfortunately sometimes even fatal.

 

The general structure

Obviously, bale loaders are based on the architecture of the classic agricultural trailer. This is demonstrated by the fact that many trailer manufacturers also produce bale loaders. Therefore, the basic elements of the machine are the bed, the axles with the wheels (possibly with front fifth wheel coupling) and the shaft for coupling to the tractor’s tow hook. In addition, bale loaders are equipped with sturdy front and rear tubular structures, and sometimes also on the long sides and top, for better positioning and proper containment of the bales. In some cases, one or more of these grilles are moved by means of hydraulic cylinders, to enable easy loading using a tractor with a front loader equipped with forks or pincers as end tools, while still ensuring maximum safety during transport.

 

The wagon

What essentially differentiates bale loaders are the types of wagon, which essentially resemble those of the common trailers. Single-axle or multi-axle wagons are available, with different placements relative to the bed, so as to unload or not part of the load on the steering shaft’s hitch, and therefore on the tractor’s tow hook.

This condition has advantages and disadvantages: one of the most important is undoubtedly an increase in traction capacity, due to the increased weight on the drive wheels. At the same time, however, attention should be paid to any excessive lightening of the front axle of the tractor, i.e. the steering axle, because this would cause a loss of precision in steering the vehicle. In such situations, the height of the tow hook should be kept as low as possible. The overall load capacity logically follows the classic categories of trailers: there are bale loaders from single axle up to three axles, from 6 to 20 tonnes (in practice, although for a long time now we shouldn’t say it, 60 to 200 of the enduring quintals...) .

It is important, however, to point out two important variants in the main elements of the bale loaders. The first variant concerns the presence of the front fifth wheel coupling, for traditional two-axle models. This is a device that allows the steering of the entire front axle, benefiting the machine’s handling, especially in confined spaces. On the other hand, compared to fixed steering shaft wagons, the manoeuvring (especially turning) in reverse is not very easy, and a certain degree of familiarity with the tractor-wagon assembly is needed. The second variant is the frequent adoption of adjacent axles and twin tyres, and in the latter case, sometimes with wide section and low inflation pressure. This technical choice has several advantages: it enables mounting wheels with a small diameter, therefore keeping the bed low and ultimately also the maximum load height, so that the centre of gravity is as close as possible to the ground (hence a greater stability) and to easily travel on roads even under low bridges. Additionally, twin wheels allows for wagons with the load capacities necessary for transporting a large number of round bales, to the benefit of the operation’s efficiency. Lastly, the adoption of wide and low-pressure tyres ensures a reduced compaction of the agricultural soil, an aspect that is increasingly valued in terms of sustainability, even in haymaking.

 

Placement of the bales

At first, it would appear that placing the bales on the wagon is a secondary factor, but that is not the case. In fact, this implies different procedures and devices for loading (and unloading), but above all it is a matter of transport efficiency, and especially of safety, particularly for round bales. If, on the one hand, laying the round bales on the flat side is more stable, on the other hand, arranging them on their outer circumference seems easier to manage, also because usually (unless working on steep slopes) the bales are left in this position in the field by the roto-baler. However, loading round bales horizontally involves the presence of sturdy front and rear containment structures in order to properly secure the load, especially the bales placed on top.

 

Loading

Undoubtedly, the leap of quality in the productivity of bale loaders was achieved with the field loading automation. This effectively eliminates the costs related to using the tractor equipped with a front loader (with related operator) for lifting and placing the bales on the wagon.

All the developed mechanisms include the capture on the ground, lifting (with possible rotation), placement on the bed and finally handling for the final positioning. There are many practical implementations, which are always devices powered by hydraulic cylinders, obviously managed directly from the driver’s seat, sometimes even with the help of remote control units.

The capture solutions are particularly interesting, using slides, pincers, levers and half-cages, which in some cases constitute the end element of more complex mechanisms, capable of rotating and displacing the bale at the same time. It is important to emphasize the sturdiness of the whole, as it must handle material weighing several hundred kilogrammes.

An interesting solution in this respect is the one by F.lli Annovi of Corlo di Formigine (MO), which uses a pair of sturdy forks to load two round bales at a time, placing them on the wagon with the flat side resting on the bed.

In general, there are two distinct bale capture solutions. In the first, the bale is loaded in line with the wagon on the short side, so that it must necessarily have a detachable steering shaft since it advances on a trajectory parallel to that followed by the tractor towing it. Alternatively, the wagon is in line with the tractor, so the loading is performed by a mechanism that takes the bale sideways and then displaces it (sometimes turning it) onto the bed.

 

Road travel

After being loaded, the bales are transported to the farm centre, so the wagon must be able to travel on public roads as well. This entails that the trailer have the mandatory equipment required in such cases, i.e. a hitch of adequate size for the load capacity, a braking system, visual signalling, etc.

In addition, some manufacturers install other devices to make it easier to handle the equipment, especially on bulkier and heavier models. Steering axles are the solution used to reduce the turning radius, while in other cases there are suspensions (often leaf spring). Among the many other accessories available, a particularly interesting one is an original system for securing the round bales on the wagon developed by Emme Enne of Nocera Umbra (PG). In the place of simple ropes or specific containment structures, it uses a shaped sheet metal structure that presses the bale vertically against the bed by means of a pair of hydraulic cylinders, thereby blocking any unwanted displacement. Meanwhile, Crosetto of Marene (CN) offers the option of a mechanical odometer in the hub of one of the wagon wheels in order to keep track of the distance and know when it is time to carry out the various ordinary maintenance operations.