Pump requirement for mulitple cylinders

[billydelo]

I am using 4 cylinders to raise 2400 pounds. Each cylinder feels 1/4 of the load. I based my pump requirement calculations off of only one cylinder (I figured out what Hp was required to raise the load of one cylinder 1.2in/sec). My reasoning for doing it this way is: If each cylinder requires the same pressure, one pump can deliver it. The 4 cylinders can be configured with one pump and receive the same pressure. So, if P=F/A and P,F,and A are constant for each cylinder it would seem that one pump can do the job. The Hp equation I used only deals with Pressure, GPM, and a .0007 constant. It doesn't consider multiple cylinders. What is the correct way to figure Hp required.

 

[danhelgerson]

If I am understanding your question correctly, you are on the right track. Figure the hp to move the load, regardless of the number of cylinders. Add about 15% to the hp as an efficiency factor. The pump is simply a device that will transfer the energy from the prime mover to the work being done. It does not know whether there is one or a dozen cylinders. The fluid will be directed to the cylinders and will follow the path of least resistence at whatever pressure is induced by the resistive load. If the the load on each cylinder is equal, the four cylinders will lift in a synchronized mannor, each receiving 1/4 the flow and 1/4 the hp. If the load is unequal, the cylinders will move in sequence from the easiest to the hardest.

 

[RBedi]

Pl also don't forget to consider cylinder's own efficiency(loss of power or pressure due to piston seal etc friction inside the cylinder)

Cheers
Rajan