Water Pressure Control

[Dymalica]

We have a situation where there is about 10 labs that use condenser water. One lab usues about half of the water requirements. We piped in a manifold system with a VFD pump to maintain a 50 psi pressure. Later they told us that every lab needs to have constant pressure (plus or minus 1-2 psi). But when one lab is running and another one starts the manifold pressure dips until the VFD can catch up. This causes instrumentation problems and they can't fully test their equipment. Is there anyway to stabilize the pressure without adding a seperate pumping system for each lab? Would a pressure reducing valve at 50 psi at each lab entrance stabilize the pressure enough?

 

[steamdog]

The pressure reducing valve may be a good idea as it would give you more exact local control, however it does waste energy. I think you have a controls issue, and there must be a way to get the VFD's to react quicker to changes in pressure. If you give us detailed control parameters on this system, maybe some of the control 'geeks' that read this will be able to help.

 

[ChasBean1]

Two things: PRV could work, but have the pump VFD react quicker to changes in pressure BUT ALSO oversize the piping. Piping with velocity over 8-10 fps may need to be upsized... CB