The heavier the bale, the better (Baling myth 1)
(This is part one of a three-part series on baling myths.)
We sometimes get inquiries about balers capable of making the heaviest bales possible. We advise against this type of thinking. Instead, we advocate the concept of creating bales with “optimal” weight. There is an important difference here. Let me explain.
Baling is done to save money on transport costs because uncompressed material takes up a lot of space and is, therefore, more expensive to transport. Most bales are transported in truck trailers or shipping containers. Most of the time, weight will be the limiting factor of how much you can pack into a trailer or container, not space. This is because even relatively “light” bales weigh a lot.
You also need to consider the “handling factor” when figuring out the optimal bale weight for your operation. Every bale adds time and effort to handle (load, stack, unload etc.) – so you don’t want a lot of very light bales either.
Let’s try some examples:
A standard European truck trailer has the following dimensions:
- Length: 13,6 meters (44ft 7.4in)
- Width: 2,4 meters (7ft 10in)
- Height: 2,7 meters (8ft 10in)
- Volume appx.: 88 m³ (3100 ft3)
- Maximum weight limit: 24 000 kg (52 910 lb)
Using light bales
Let’s say we want to transport cardboard bales with the dimensions (height × width × length) 750 × 1100 × 1200 mm. With the bales being this size, space is not a problem – we can fit two rows of bales in the trailer, each row being three bales high. This way there is room for 66 bales in one truck. Cool!
But there is a problem. Each bale weighs 500 kg on average (a pretty standard weight) and 66 × 500 = 33 000 kg, which is 9 000 kg over the weight limit if we would fill the entire trailer. No good. The truck is now overweight, and we are stacking the bales three high. Even if we only load the 48 bales needed to match the weight limit, we need to stack some bales three high. That’s not optimal. We want to avoid unnecessary handling and stacking.
Using really heavy bales
Let’s try again using heavier bales so we don’t have to transport so many of them. We will let the baler compress them really hard (using a lot of electricity doing so) and get the bale weight up to 1050 kg. We can now fit 22 of these high density bales (23 100 kg) in one trailer, in just one layer, and be below the weight limit. This works. But it will cost a lot of electricity and you need a really powerful (and probably expensive) baler.
Creating optimal recycling bales
How about using “optimal” weight bales instead? In this particular case 44 bales, each weighing about 540 kg, would fit nicely in two rows and two layers. The weight? 23 760 kg, which is 240 kg below the limit. By doing it this way you can use a smaller baler and less electricity and still fill the trailer.
That’s why “optimal” is better than “heaviest”.