|
Characteristics of an Air Bag
Compacting and positioning the lading
Compacting and positioning takes place during air bag inflation. The air bag
surface pushes uniformly out
against the load. As the air pressure increases, it
overcomes frictional forces,
eliminating small voids remaining in the load. No matter how tightly a load is
positioned, either by fork truck or by hand, a build up of small voids remaining in
the load. These voids are eliminated by air bag compacting/positioning.
Cushioning the lading
The
second characteristic of air bag bracing is the cushioning that occurs during
impact. For example, when a
railcar is humped, the compacted lading in the front half acts as one unit
rather than individual units which can slam into one
another. The rear half of the
load is cushioned by squeezing the air bag,
increasing its internal air
pressure, until equalization of forces occurs. The
cushioning effect diminishes
after shock of impact.
Repositioning the lading
When
the forward motion of the lading ceases, repositioning of the lading
begins. After the lading moves
forward, squeezing the air bag, the internal pressure is greatest. The
increased air pressure is reduced by pushing the lading
back to its original position
when the forces stop. Both the cushioning and
repositioning of the load will
take place in a fraction of a second.
Enlarging the void size after inflation
Another characteristic of air bag bracing is its ability to fill an increased
void as the lading settles. Even with
rigid products, which have been tightly loaded, settling takes place. In-transit
vibration causes the lading to loosen. With other
types of bracing, constant
pressure cannot be exerted on the load. Air bags
have the ability to expand, thus
maintaining somewhat reduced but continuous
pressure.
Dunnage Product Line |