- #1
John Archer
- 23
- 13
- TL;DR Summary
- Controlling (liquid) flow and pressure going to a packing that is meant to slowly leak cooling water.
System in question. Centrifugal pump (seal packing is water cooled)
Fluid is water. Main system pressure is 55Psi.
I need the water pressure to be around 25Psi.
I also need the flow rate to be very low (think, maybe 1oz per minute). Basically, I need slightly more than say 30 drops per minute.
The pressure in the system that the pump runs is between 6-10Psi. I need to keep about 1 Bar (14-15Psi) of pressure above that of the system pressure to prevent the fluid the pump is running from getting into the seal packing.
The problem is that I can't have too much cooling water going to the packing as it can thin out the fluid the pump is pumping. an oz. per minute would be an absolute maximum.
So the process allows a very small amount of fluid flow/loss, but I need to keep the pressure up to keep the packing clean. The flow control is mainly to prevent dilution if the packing starts to wear out.
I am using a regulator to get the pressure to 35Psi, and a flow control to limit flow. I have added a 2nd pressure gauge after the flow control, and it reads a lower number (as it must) than the regulator's gauge.
I am wondering if I should put the flow control in front of the regulator instead of downstream.
One more variable to consider; the packing is adjusted by compressing it. the more compression, the more resistance (the closer to 2 gauges will read to each other), but also this generates more heat, needing more flow.
I can also adjust the distance from the pump, flow control, and regulator. At the moment,the regulator is connected to the flow control, then about 18" of hose going to the pump (1/8" ID, that can be changed to a larger or smaller diameter).
Short version, I need to get 25 Psi of water to go to a packing, to cool the packing, too much flow can ruin the product. Where would you put a regulator and/or a flow control?
Thanks
Fluid is water. Main system pressure is 55Psi.
I need the water pressure to be around 25Psi.
I also need the flow rate to be very low (think, maybe 1oz per minute). Basically, I need slightly more than say 30 drops per minute.
The pressure in the system that the pump runs is between 6-10Psi. I need to keep about 1 Bar (14-15Psi) of pressure above that of the system pressure to prevent the fluid the pump is running from getting into the seal packing.
The problem is that I can't have too much cooling water going to the packing as it can thin out the fluid the pump is pumping. an oz. per minute would be an absolute maximum.
So the process allows a very small amount of fluid flow/loss, but I need to keep the pressure up to keep the packing clean. The flow control is mainly to prevent dilution if the packing starts to wear out.
I am using a regulator to get the pressure to 35Psi, and a flow control to limit flow. I have added a 2nd pressure gauge after the flow control, and it reads a lower number (as it must) than the regulator's gauge.
I am wondering if I should put the flow control in front of the regulator instead of downstream.
One more variable to consider; the packing is adjusted by compressing it. the more compression, the more resistance (the closer to 2 gauges will read to each other), but also this generates more heat, needing more flow.
I can also adjust the distance from the pump, flow control, and regulator. At the moment,the regulator is connected to the flow control, then about 18" of hose going to the pump (1/8" ID, that can be changed to a larger or smaller diameter).
Short version, I need to get 25 Psi of water to go to a packing, to cool the packing, too much flow can ruin the product. Where would you put a regulator and/or a flow control?
Thanks