Baletite is manufactured in two film widths: 1280mm mainly used for maize and sugar beet silage bales 1380mm mainly used for grass silage bales.

Transcription

1 Copyright 20/5/2015 formipac & minster films In recent years balers capable of applying a wide polythene film in place of conventional netwrap have entered the market in significant numbers. The successful launch of these new balers not only offers enhanced throughput and efficiency levels for agricultural contractors but also enhanced silage quality with a notable reduction in silage moulds for the end user. formipac has been at the forefront of global field trials of netwrap replacement film following several years of research and film development. In this article Johan Rubbrecht, R&D Manager, Stretchfilms at formipac and minster films, shares his experience and findings regarding the new generation film known as Baletite. Baletite is manufactured in two film widths: 1280mm mainly used for maize and sugar beet silage bales 1380mm mainly used for grass silage bales. The bale chamber width for 1250mm. all existing grass and maize balers is between 1200mm and Baletite is tensioned before it is applied around the bale circumference. During tensioning, the film necks-in, meaning that the film width narrows before it enters the bale chamber. The degree of neck-inn depends on the stiffness of the film, the stretch %, the ambient temperature and the distance over which the film is stretched. After tensioning (which must be between 5% and 15% stretch for Baletite): Baletite 1280mm necks-in to a film width of approximately 1250mm on entering the bale chamber Baletite 1380mm necks-in to a film width of approximately 1350mm on entering the bale chamber. Baletite 1280mm covers the bale across the width of the bale up to the bale edge, but does not reach over the bale edge as shown in picture 1 opposite. Picture 1.

2 Baletite 1380mm covers the he bale across the width of the bale and over the bale edges as shown in pictures 2 and 3 below. below Picture 2. Picture 3. Covering the bale edges has some important advantages in grass silage bales: bales No shoulders on the bale: bale Covering the bale edges ensures that no shoulders are created which means that the bale will be of a much more cylindrical shape. Cylindrical baless benefit from a much better airtight and watertight seal when wrapped with silage ilage stretchfilm. stretchfilm Easier to wrap with silage stretchfilm on the bale wrapper: During uring wrapping (at ( the wrapper arm rotation rotati stage) the stretchfilm always makes first contact with the bale edges.. When these edges (and in particular those containing stalky and high dry matter content grass) grass have already been protected by layers of Baletite, Baletite the risk of the stretchfilm being punctured or torn by the bale edges during wrapping is significantly reduced. Picture 4. Eliminating puncture points: Because the tension on balewrap is maximised on the bale edges, there are often small points visible in the stretchfilm around the bale edges see picture 4 above. above It can look as though the film is punctured and that th the edges are nott well protected. prote Sometimes the first layer(s) of stretchfilm really are punctured. When bale edges are protected by Baletite, these points are covered by additional film layers thereby making them less visible in addition to reducing the risk of punctures. The absence of these points from the bale edges reassures users that the film is intact and the silage is not at risk of spoilage.

3 ON THE EDGE or FOLDED OVER THE EDGE Sometimes, the Baletite 1380mm film does not fold over the bale edges. Instead it wrinkles together on the bale edge - see picture 5 opposite. Picture 5. When the film enters the bale chamber, it is more than wide enough to fold over the bale edges. Upon entering the chamber chamb the film has to slide between the grass (of the bale) and the sidewall of the bale chamber, chambe but this movement can be restricted by a coarse grass crop and its dry matter content - see ee figure 1 and figure 2 below. Figure 1. Figure 2. When this occurs the Baletite film wrinkles wrinkle on the bale edges. In such uch circumstances Baletite is still covering the bale edges edge and in so doing it provides the same benefits as when it folds over the bale edges i.e.: no shoulders on the bale, easier balewrapping and less risk of balewrap puncture. Ideally Baletite should always be folded over the bale edges for all types of grass crops but when en the nature of the crop prevents this, Baletite continues to provide effective on the edge protection. Making a film more slippery would help to ensure that it folds over the edges however it is important to understand that a film that is too slippery has some significant disadvantages as follows: Upon leaving the bale chamber a slippery film tail will not adhere to the bale, bale will open out and will fall from the bale surface. surface In windy conditions the film can even blow away from the bale. In non-combi-balewrapper wrappers (where the baler and balewrapper are separate) the film will easily loosen or fall from the bale during transportation to the wrapping location.

4 The nip rollers (whichh push the netwrap replacement film into the bale chamber at the start of the baling cycle) can slip over a slippery film. As a consequence the film will not be pushed into the baler and therefore not caught by the rollers inside. Similarly the rollers in the bale chamber (that pull the film around the bale) can slip over a slippery film and as a consequence the required number of layers will not be applied to the bale. This is certainly not recommended and is very risky because an underwrapped bale could burst open subsequently. When the bale leaves the chamber, the bale diameter could increase in size because the slippery film layers have not sealed together correctly meaning one layer could slip one over another. Such less compressed bales do not offer sufficient protection levels for the silage inside. So, making the film slippery creates important disadvantages and is certainly no solution. Making the sides of the bale chamber more slippery - thereby making film entry into the bale chamber as smooth as possible - helps to get the film over the edges better but it does not solve the problem. Experience has taught us thatt with very humid/wet grass the film always folds over the bale edges. This is logical becausee wet grass is already slippery and is therefore lubricating the chamber during the baling process in addition to lubricating the film during the film application process. Conversely with very dry, long, hard and prickly grass, the film is less inclined to fold smoothly over the edges. HOW TO ENSURE THE FILM ALWAYS FOLDS OVER THE BALE EDGES Picture 6. During the 2014 and 2015 season, formipac carried out trials that involved spraying water either side of the film borders. Water was sprayed approximately 60mm from one side of the film just before it entered the bale chamber (see picture 6 opposite). We started to spray when the film was widened and stopped before the film began to narrow. The water was sprayed onto the outer surface of the film (which is the cling side and which is the side that is in direct contact with the bale surface). On the side where the water was sprayed the film was lubricated as well as the grass and those parts of the bale chamber the film came into contact with. This method was tried on hundreds of bales with a successful end result as, even with Picture 7.

5 difficult, dry, hard, prickly grasses grass the Baletite film folded over the bale edge in the majority of cases. See picture 7 above and the accompanying video on this web page. To apply this solution professionally professional the baler requires a small water tank and two water sprayers located at both sides of the film borders. The sprayer should be set to spray water when the film is widened and to stop before the film begins to narrow. The spray system should have a spray time and/or flow setting. Not much water needs to be sprayed because the chamber is lubricated with a spray each time a bale is processed. It is important to note that the dryer the crop the more water spray is required. required However never overdo the amount of water you spray. spray Currently, we are investigating the possibility p that the water can also be sprayed spraye between two bale chamber rollers onto both the edge of the bale and the side wall of the balechamber. This may be a better solution but bu is still being tested. This water spray system is quite an easy solution for ensuring the film folds fold over the grass bale edges in all circumstances and importantly, it has no effect on the silage. silage Further trials will be undertaken in the near future but already there are some contractors considering the installation of a water tank and two water sprayers on their thei combi-balewrappe wrapper. Johan Rubbrecht R&D Manager, Stretchfilms formipac & minster films Should you have any questions in relation to this article or requiree further information please contact us via: Sales Office, Belgium: Sales Office, UK: