Many producers of dry bulk solids, who have traditionally shipped their products in drums, boxes or rigid totes, want to take advantage of the financial benfits of converting to bulk bags. 

However, it is often difficult to convert every customer at once.  That means that for at least some period of time bulk bags and the legacy package(s) must be filled.

The problem is how do you handle having to fill multiple packages with multiple packaging machines? 

Changeover can be a significant challenge particularly if your current packaging machine is not portable.  Production scheduling and the time required to simply change from the existing packaging machine to the bulk bag filler can be barriers that prevent companies from benefiting from bulk bags.

What's the answer?

A multiple-package filling machine.  Purchasing a bulk bag filler that also fills drums or boxes or rigid totes - or ALL of these packages - is feasible and economically very attractive.

Filling multiple packages on one machine requires more up front capital as compared to a machine designed to fill only bulk bags.  However, the operational benefits of using a single machine that automatically changes its configuration to fill up to four different packages are significant.

Just think, no delays for changeovers AND you can satisfy those customers who have not yet converted to bulk bags.  A good deal I think.  Plus, there's the financial benefits that immediately hit your bottom line from converting to bulk bags... but that's another story! 

We often run across bulk bag users who subscribe to the idea that bulk totes MUST be inflated before filling.

Not true!

It's understandable why this common practice exists and why it persists: through-pallet densification FIBC fillers.

A through-pallet bulk bag filler is characterised by the bag resting on a pallet throughout the fill cycle.  As you can imagine, if a bulk bag is attached to the filler and left to drape randomly on the pallet prior to filling, it is possible - perhaps likely - that the bag will become twisted or folded on itself and not fill properly.  Hence, bags are often inflated prior to filling when a through-pallet filler is used.

While inflating a big bag is generally a good idea with this kind of bulk bag handling equipment, it takes time during the filling cycle and adds capital cost.  However, there is an alternative.

If you use a filler that features hang filling - the bag hangs from its loops for about half the time it is being filled - you don't have to inflate your bulk bags.

A key characteristic of this type of filler is that a pallet is NOT in the machine while it is filling bulk bags.  Because the bag is not in constant contact with a pallet and because the bag is hung from its loops, you don't have to worry about poor performance from not using inflation.

With a hang filling bulk bag loader the ONLY time you need to use inflation is if your bags contain loose tubular liners.

Stacking bulk bags CAN be done safely.  There are a few things to carefully consider before attempting to stack FIBCs, but if you do your homework and if testing conducted with your product and bulk bags proves they can be safely stacked, the increase in warehouse efficiency can be a remarkable financial benefit.

Here are the things to consider before attempting to stack bulk bags:

1. Is the nature of your product conducive to stacking?  Some dry bulk solids are easily fluidized and behave like a liquid, others densify like a brick.  Where does your product fit within this spectrum?
2. Are your bulk bags properly designed to facilitate stacking?  Unique bulk bag designs exist with features specifically aimed at aiding stacking stability such as stand up loops, strategically placed gussets, etc.  Do you need these features?
3. Is your filling equipment up to the task?  Does your filling equipment densify your product enough to produce a safe and stable FIBC capable of being stacked?

The best way to determine the answers to the above questions is to work with your big bag and filling equipment vendors.  They should be able to conduct tests that will prove that your product can be stacked safely in bulk bags.

Regarding benefits, double stacking doubles your storage space utilization.  Triple stacking improves warehouse efficiency by another third.  And, quadruple stacking - yes it can be done! - reduces your bulk bag storage footprint by a factor of four compared to not stacking at all.

As you can see stacking bulk bags can provide a huge improvement in warehouse efficiency and profit improvement.  If you're interested contact your bulk bag and equipment suppliers and get stacking!

Bulk bags, FIBCs, bulk totes - call them what you will - are usually sized to contain one ton or metric ton of dry bulk solid material.

However, we've seen bulk bag payloads as small as a few hundred pounds and as big as 5,000 lb and more.  That being said, you may be surprised at how often we are asked the size of 'standard' bulk bags - as if there is only one size.

The fact that bulk solids have different bulk densities - usually expressed in pounds per cubic foot - means that for a bulk bag to contain a specific weight it has to be sized accordingly.  For a given weight, a bulk bag filled with a lower bulk density product will be bigger than one filled with a higher bulk density product.

That means that bulk bags end up being whatever size is required to contain the weight of product you want to package.  I.e. there is no 'standard' size!

Here's the basic procedure to size a bulk bag: 

1. Determine the method by which your bulk bags will be shipped: truck, rail, shipping container, etc.  This will determine the maximum width and depth of the bulk bag (and the pallet size if you're using them - you don't have to!).
2. Once the base dimensions have been determined calculate the bag volume required to hold the payload and then calculate the height using the known cross sectional area of the bag (base x width).

So, remember that there is no such thing as a 'standard' size bulk bag and that yours needs to be sized to your specific requirements.  Any reputable bulk bag vendor will be able to quickly determine the right size bag for your application - and then test it with your actual product to fine tune their calculations.