Flow reducer question

[Devin5]

Hi,

I am trying to reduce the flow of water off a main line into a storage tank. currently we are using a half closed ball valve to restrict the flow entering the tank to 6 L/s. With the ball valve fully open, the service water pump is unable to feed both the tank and other processes in the plant, which requires 1 L/s. The inline pressure is 60 psi (415kpa) which is near the location of the pump.From the pump, the water is then sent through 6 inch pvc until it reaches the location where it fills a storage tank (a few meters away). At this location the piping reduces to 3" diameter and is sent through the half closed ball valve and into a tank a few (3) meters away. Another line branches off the 6" line (6m before the ball valve) into a 3" line and is sent through a booster pump. What would be the best way to reduce the flow into the tank without the use of a ball valve? Would a pressure reducing valve work or and orfice plate? What size or recomendations for this problem?

Thanks

 

[hydrae]

I would suggest a pressure sustaining valve with full tank override
this will allow the filling of the tank at the maximum rate while maintaining service to the rest of the system
These valves are available in pilot operated diaphragm control globe valves such as Cla Valve

Hydrae

 

[katmar]

The real question is what flow rate is required into the tank. You could install any manner of valve, controller or orifice plate but if insufficient water flows into the tank for process requirements then you have not really got a solution. Is the flow out of the tank intermittent, cyclical or steady? Without this information any proposal is just a shot in the dark.

Katmar Software - AioFlo Pipe Hydraulics

http://katmarsoftware.com

"An undefined problem has an infinite number of solutions"

 

[bimr]

The least expensive approach is the orifice plate. The orifice plate will function in the same manner as your half closed ball valve. The problem with the orifice plate is that there is no adjustment as the flow/demand requirements change. The orifice plate area will be approximately the same area as taken up by the half closed valve. You can use an orifice equation to determine the size of the orifice plate.

Another approach is to install a control valve on the tank, a level transmitter on the tank, and a level controller. With the level controller, you can set the rate that you want to fill the tank.

The third approach is the pressure sustaining valve. The pressure sustaining valve will maintain the backpressure and fill the tank with the excess water while maintaining the backpressure. Cla-Val will determine the size of the valve for you.

http://www.cla-val.com/01/650-pressure-relief-pressure-sustaining-valve-p-77-l-en.html