9
Tanco Autowrap 1300 EH
Operator’s manual
3.0 GENERAL INFORMATION ON BALE WRAPPING.
3.1 THE PRINCIPLE.
The advantages of round bale silage are many, and include fewer feed units, a flexible harvesting
system, large capacity and the possibility of selling feed units.
In principle, the same fermentation processes occur whether the fodder is placed in a silo or
pressed into bales and packed in plastic, i.e. lactic acid fermentation in anaerobic conditions. The
oxygen in the bale must be exhausted before fermentation begins.
The grass should be dried to approximately 30-40% solid content. The solid content can be
determined by twisting the grass by hand. If drops of liquid are forced out of the grass, the solid
content is less than 25%. Low solid content, (wet grass), can lead to increased butyric acid
fermentation if preservatives are not added to the grass. If the solid content is too high, (over 50%),
normal fermentation will not take place and there will be enough oxygen in the bale to produce
mould fungus.
3.2 THE BALER.
It is vital that the baler produces compact, well-formed bales, as misshapen bales can be difficult to
wrap. Wrapping will also often take longer, thereby increasing the amount of plastic used.
3.3 DIFFICULT BALES.
When a misshapen bale is wrapped, it will have a tendency to move outwards or inwards on the
roller. If the bale begins to move outwards, the machine must be lifted slightly at the rear edge to
get the bale to rest against the support roller on the main frame. It can therefore be useful to use a
hydraulic top link to make this adjustment easier. (See chapter 4.2).
If the support roller almost disappears into the bale the machine should be pressed down slightly at
the rear edge in order to remove the bale from the machine. The plastic can be damaged when
friction against the roller increases. Best results are achieved when the bale rolls easily against the
support roller all the time.
If the bale to be wrapped is conical you must ensure that the sharp end is pointed at the tractor. It
will then be easier to get the bale to lie correctly during packing. It is easy for such a bale to "turn"
forward in the direction in which it is pointing, and therefore lie against the support rollers. If the bale
is lying on a slope it must be picked up from the lower side. A hydraulic top link will again be
advantageous.
3.4 TYPES OF PLASTIC.
A good type of plastic with good adhesive properties, and which is recommended for bale wrapping,
must be used. The thickness of the plastic foil should be at least 25 µ. (25/1,000 mm). In order that
the plastic tightens sufficiently around the bale, it is stretched before being wrapped, so it is
somewhat thinner when it is put on the bale. With short-term storage, (up to eight weeks), it is
recommended that bales have a minimum of four layers of plastic at the thinnest points, with at
least 52-53% overlap.
For long-term storage, or when the grass is wet when it is wrapped, the bale should have 90-100 µ
plastic, (6 layers), and the same amount of overlap. If thinner plastic is used, more layers should be
applied. If it is very hot the plastic will be stretched further, and more layers should be applied. It is
better to have slightly too much than too little plastic on the bale.
