Effective wrap with new system
Effective wrap with new system
SAVING time, labour and machinery, wrapping inside the bale chamber might seem like the easiest and quickest way of applying film.
But developing a system which works effectively has created a conundrum for baler makers.
The challenge has been to find ways of applying film evenly under tension with little risk of breakage.
After three years development, New Holland claims to have perfected a system designed to work with its 544/548 fixed and 648/658 variable chamber round balers.
The device applies a 1.2m wide film and can be fitted to fixed chamber machines without any modifications, with variable chamber balers requiring a conversion kit costing £500.
The system has two main rollers with a duckbill plate system to place film positively around the circumference of the bale.
Improvements to the system to ensure a positive feed include a separation device to keep film layers apart and a one-way roller bearing to prevent film tearing after being cut.
Another factor deemed important to prevent film breakage and achieve a watertight bind is use of high quality film that has the correct amount of adhesive, says New Holland.
Surrey contractor Tony Leach has been using the system on his two 648 machines for the past couple of seasons, having baled and wrapped over 5000 bales.
Based near Oxted, he started using a prototype system in the late 1980s to meet increasing demand from his customers wanting to preserve the quality of straw bales stored outside.
His customers consider barn storage space to be precious which has prompted the need for bales outside to be better protected.
"The film applicator system we operated a decade ago was unreliable. One in 10 bales was not properly wrapped due to film becoming loose and falling off," says Mr Leach. "This was because the film had no adhesive and had to be bound on with twine after the wrapping process."
Finding film with the right amount of adhesive is important to ensure bales are bound tightly, he adds.
Too sticky and the film will wrap round the rollers, while not enough adhesive will cause the film to become loose and fall off.
In the quest for a happy medium, Mr Leach claims to have found a suitable make of film with enough adhesive to bind and wrap bales securely.
In operation, the film applicator works in a similar way to a conventional twine or netwrap system, with the bale covered in wrap after the formation process.
Mr Leach says wrapping time is the same as a twine or net wrap system, helping to maintain baling work rates, which are 200 a day for straw and 300 a day for haylage.
To help achieve 70% dry matter, haylage bales are covered with 2.75 turns of film, with straw bales requiring an extra turn to protect against abrasive crop.
Mr Leach says straw bales have to be 100% dry before wrapping to eliminate the risk of condensation causing mould during storage.
Using the current application rates, Mr Leach aims to cover about 100 bales with a 1200m roll of film, which costs £80.
Wrapping costs equate to 80p a bale, compared with 40p a bale for net wrap application.
"To offset higher wrapping costs, we add an extra 10% surcharge per bale compared with net-wrapped bales," he says. "The main advantage for our customers is having a means to protect bales against the British weather, resulting in significantly reduced crop damage."
From a commercial point of view, Mr Leach says high quality haylage or barley straw wrapped with two or three layers of film could be sold at a premium price.
An advantage, he says, is the ability to leave wrapped bales longer in the field before collection in bad weather and when there is a shortage of men and machinery.
For collection, wrapped straw bales can be picked up with a conventional bale spike and stacked horizontally in pyramid formation, although Mr Leach believes bales would be better protected if stacked in a tin can fashion.
After haylage bales are wrapped around their circumference, they are wrapped entirely with a dedicated trailed wrapper in the field.
This allows the trailed machine to apply four rather than six layers of film, cutting wrapping costs, and for the bale to receive an even amount of film around its sides and circumference. *
IN-CHAMBER WRAPPING
Benefits
• Weatherproof bales.
• Higher quality crop.
• Leave in field longer.
Banes
• Costly film.
• Crop moisture critical.
• Risk of miswraps.