Photo By: JJ Cassetta
How much will your bags lift? How do you calculate? How many bags are you WILLING to STACK?? What do you have to complement your air bags? How does this ditch complicate things? How high can your box crib be, using air bags?
What are your capabilities with air bags?
Northwest Florida has had an extremely busy year with air bag operations. From cars under trucks & buses, to trucks upside down in ditches. Numerous calls with civilians trapped under vehicles. Make it a drill on how fast you can get your bags ready and lift something around the firehouse.
Well here is my thought on this topic. A general knowledge on placement, working limits, operating procedures and uses is a MUST for all members. Just because you are not assigned to the company that is responsible for the equipment does not mean you won’t be using it.
It takes a team to have a successful incident. Maybe the advanced techniques are just for that company. But on the other hand if you can train the entire department on every application of the tool then do it.
We don’t have them anymore ….but they are a great asset no doubt.
Lift capabilities of air bags are as follows, Maximum working capacity is proportinal to the maximum contact surface area of the bag ( always smaller than the bags dementions) times the maximum working pressure of the bag ( depending on brand). Always remember as the bag lifts and pillows surface area is decreased therefore lift capacity is decreased. Example, 10″ by 10″ bag with a working pressure of 118psi ( 10×10=100 times working pressure 118 is 11800lbs at one inch lift). As you inflate the bag pillows and the contact surface is now 5″ x 5″ wich is now what capacity? 2950lbs very significant loss in lift capacity. So think about that when stacking bags. Some say no more than two. I agree if you are trying to achieve a high lift. If one only needs 5″ of lift but has a very heavy load to move you may stack more than three but only inflate each 1.5″ so you won’t loose lift capacity. As for cribbing heights, two times the width of the base. 6000lbs per contact point total of 24000lbs (4×4 cribbing). As for six by six cribbing same rule of thumb for height but capacity is 15000lbs per contact for a total of 60000lbs total capacity.