PEDARRIN2
Mechanical
- Oct 1, 2003
- 1,287
I am trying to design a domestic water softeing system (salt regenerated) where the client wants to mix hard water back in with the softened water to achieve "less soft water". To achieve the requirements, the flow ratio is 25% hard water with 75% softened water. This has to happen in variable flows, from ~1 gpm up to about 50 gpm.
I found a valve that I think will work ( but I am trying to figure out how to set the flow restrictors at point A and point B. I haven't designed with fixed orifice fittings in a plumbing system so was thinking of using a partially open globe valve for both locations.
I am assuming I need to have the same gauge pressures in both lines upstream of point C to insure the correct flow ratio and I am assuming that is why the control valve has sensing lines for both flows and will control the flow in the high pressure pipe compared with the flow in the low pressure pipe.
But I am uncertain of how to set up the throttling valves (or orifice and throttling valve) to achieve this over the flow ranges. Both an orifice and a throttling valve will have different pressure drop characteristics based on the flow rate, so one setting or orifice size will not (??) work for all flow rates, unless the control valve takes care of this.
Any assistance would be appreciated.
I found a valve that I think will work ( but I am trying to figure out how to set the flow restrictors at point A and point B. I haven't designed with fixed orifice fittings in a plumbing system so was thinking of using a partially open globe valve for both locations.
I am assuming I need to have the same gauge pressures in both lines upstream of point C to insure the correct flow ratio and I am assuming that is why the control valve has sensing lines for both flows and will control the flow in the high pressure pipe compared with the flow in the low pressure pipe.
But I am uncertain of how to set up the throttling valves (or orifice and throttling valve) to achieve this over the flow ranges. Both an orifice and a throttling valve will have different pressure drop characteristics based on the flow rate, so one setting or orifice size will not (??) work for all flow rates, unless the control valve takes care of this.
Any assistance would be appreciated.