Flow rate vs pressure
Flow rate vs pressure
(OP)
Hi all, i have very simple question regarding the flow of air in the common plastic pipes.
I work in a a machine shope where compressed air is being used for operating several devices like plasma cutting, cnc machines, pneumatic drills etc. We have a compressor installed having a rated value of pressure and flow rate. I want to ask that if air being used by more than one devices at the same time then what happens to values of pressure and flow rate? will the pressure and flow rate be divided? also are the pressure and flow rate inversely proportional to each other?
Thanx all in advance
I work in a a machine shope where compressed air is being used for operating several devices like plasma cutting, cnc machines, pneumatic drills etc. We have a compressor installed having a rated value of pressure and flow rate. I want to ask that if air being used by more than one devices at the same time then what happens to values of pressure and flow rate? will the pressure and flow rate be divided? also are the pressure and flow rate inversely proportional to each other?
Thanx all in advance





RE: Flow rate vs pressure
As end-uses consume air, they draw the pressure of your air system down. When the pressure reaches the "load" set point on your compressor, the compressor turns on and supplies air to the system until the pressure increases to the "unload" set point on your compressor. Here the compressor unloads (or turns off) until the pressure drops back to the "load" set point again.
In other words, the compressor (if fixed speed/volume) is either full load or off. The demand only changes how often and how long the compressor is at full load for.
Does this answer your question?
RE: Flow rate vs pressure
You need to think of this as a mass issue. If the mass or air being input into the system (pipes, accumulator etc) is greater than that being consumed then pressure will go up. If less then pressure will go down. By how much depends on the margin and how much that is compared to the total mass in the system.
Depending on how your system is set up and the size of the piping you could find that operating some machines at the same time has a bad effect on others, but if you could increase the pipe size, then this effect might just go away.
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
RE: Flow rate vs pressure
The OP didn't make any specific mention of pressure problems, so I'm not sure if it's relevant. Regardless, it's a very good thing to point out.
RE: Flow rate vs pressure
Main pipe line is from A to D, at point B we have a valve from where we are taking air for our cnc machine, at point C we have taken air from main pipe line for our plasma cutter. What will be the pressure and flow rates in pipe B and C? Compressor discharge is that 8 bar, what pressure and flow rate we will get in B and C?
RE: Flow rate vs pressure
The short answer is, in 99% of cases, it doesn’t matter what the exact pressure and flow rate is at all branches in your line. It’s simply not required to solve most of the problems you might be facing.
RE: Flow rate vs pressure
RE: Flow rate vs pressure
The change in flow and pressure is the consequence of the system behaviour and compressor response.
I dont understand the original post - sorry.
"If you want to acquire a knowledge or skill, read a book and practice the skill".