Hi, I’m Gary Mollohan, marketing manager for Airfloat. In this video, we’ll be looking
at how air bearing technology can be used alongside mobile cranes to move a large, extremely
heavy object. In this case, a seventy-thousand-pound backup roll used in steel production had to
be moved out of warehouse and onto a flatbed trailer. The decision was made to use Airfloat
air skids to float the backup roll outside the warehouse and then a pair of mobile construction
cranes to lift the roll onto the flatbed. But let’s back up a moment and look at a
few things in greater detail. First, you’ll notice that the backup roll is resting on
an improvised cradle made of tubular steel. That, as you might guess, is necessary to
prevent the backup roll from rolling off the air skids. The cradle, in turn, is sitting
on multiple steel air skids. The air lines are all attached to a single controller, allowing
the air for all skids to be turned on and off and regulated simultaneously. The skids
are all twenty-inch steel air skids, each of which has a rated capacity of eight thousand,
two hundred and fifty pounds. There are nine skids in the setup, giving the system a total
capacity of more than seventy-four-thousand pounds. Total air consumption is one hundred
and sixty-two c.f.m. at sixty p.s.i. Slightly complicating this move was the less than ideal
transition from the smooth, trowel-finished shop floor to the rough, porous parking lot
concrete. You’ll notice there were some wide cracks and seems, which can channel the
air away from air bearings and cause a loss of lift. There was also a slight difference
in surface height, so a temporary platform was created to smooth this transition. First
sand was spread out and leveled, using stacks of washers and thin strips of metal as leveling
guides. Then a piece of half-inch steel plate was laid on top of the sand, followed by a
thin sheet of galvanized metal. Tape was applied to further smooth the transition and prevent
slippage. Then it was time for the first part of the move. The air was turned on, lifting
the seventy-thousand-pound backup roll a few millimeters off the ground. Then it was easily
pushed across the shop floor and onto the temporary platform. You’ll notice that Airfloat
air skids are self-braking. When the air is turned off the air bearings deflate, gently
lowering the load to the ground. The rest of the move was a fairly typical rigging application.
A pair of Link-Belt telescopic boom cranes were used, each with a one hundred-ton capacity.
Nylon lifting straps were looped around each end, and the roll was carefully lifted off
the ground. This may sound a bit self-serving, but this was the most hazardous part of the
entire operation, in our opinion. The roll was about ten to twelve feet off the ground
at various times, the cranes had to move in concert with one another to keep the roll
level, and multiple spotters were required. Again, let’s compare that to the first phase
of the move. The roll is inches off the ground, as opposed to feet. And it’s moved by human
power alone, as opposed to mechanical means. About the worst thing that could happen would
be for the air to suddenly cut off. But as we previously saw, that would just bring the
backup to a gentle stop. And there you have it – a great example of how to incorporate
air bearing technology into your next move. Check this website often for more application
ideas and other useful information. Goodbye.
