Thread: Pneumatics Question

Tweet

I have a coffin lifter mechanism that failed this year last minute. I welded a new mechanism but it takes 50 PSI to lift and most of my props are running 30-40psi. While I could use more regulators, I have seen some prop lifters build with 2 pneumatic cylinders in tandem. Does this effectively double the lifting power? Would it allow me to cut the PSI by some factor? Would that factor be 50%?

Thanks!!

The lifting power of a pneumatic cylinder or combination of cylinders is directly proportional to the area of the piston or in case of multiple cylinders their combined area, so yes more cylinders does equal more power, and two cylinders will give you twice the lifting power of 1

However..... its not guaranteed that both cylinders will lift at the same rate, if the two cylinders are either end of the coffin and there is more weight on the one end then the other end may try and lift faster than the heavy end, the closer the cylinders are the better.

You can limit this effect by using flow regulators on the cylinders to balance the rate of opening.


My recommendations however would be

1) Run the system at 100psi

2) Don't use cheap home made pneumatic cylinders of any description, not even the dor closers that some people are selling as cheap cylinders.

3) Use FLOW regulators where you want to limit the speed that a prop moves at NOT pressure regulators

4) flow regulators are used to regulate the flow of air LEAVING a cylinder not entering.

5) Use PRESSURE regulators to limit the pressure to individual props that need lower pressure, but only if you really want lower pressure, not lower speed.

Thanks for the great information. This forum is invaluable.