Pressure Drop Questions

[RJB32482]

OK I have a few questions about a problem in our glycol chilling units.

A brief description:
Glycol is pumped and fed to two different precooling units (exchanger and compressor) in a continuous loop. The one side passes through 2 expansion tanks and the other just one (1 common exp tank for each). We are getting back flow into one expansion tank and its overflowing (both are pretty much atm pressure).

Would pressure drop through the pipe cause this to occur (suction pressure of the pump is 400 psi so if pressure in pipe goes less than 400psi backflow can occur). Discharge is 1000 psi

In general is that the main thing pressure drop gives you in all applications. How does pressure drop come into play with design and troubleshooting?

Thanks

 

[quark]

Your question is not very clear and I feel difficulty in visualizing the system. If the expansion tanks are at atmospheric pressure then how do you get 400psi at pump suction?

 

[jcfoley]

I agree with quark. However, it seems to me that you have two precooling units in parallel. If this is so, then the pressure drop for both legs will be the same. The flow will "adjust" itself for the required pressure drop. Do you have balancing valves installed? I do not see how you can backflow but the system is not clear from your discription.

 

[Latexman]

Is the line to one tank partially plugged (or valve partially closed), thereby causing the other tank to overflow?

Good luck,
Latexman