Check valve in Pumped SS line
Check valve in Pumped SS line
(OP)
I am designing a small SS lift station with a grinder pump. After the pump, the line needs to go horizontal for 100 ft. before rising up 10 ft. I need to prevent the line from draining back into the sump. Can a check valve be used at the pump discharge? What about the settlement issue on the horizontal section of the pipe?
thanks,
thanks,





RE: Check valve in Pumped SS line
Solids do not settle out if the velocity in the force main is a minimum of 2 ft/sec.
Solids do settle out at lower velocities or when the pump is stopped and a velocity of 3.5 ft/sec or greater is then required to resuspend the deposited solids.
A small to medium size pumping station with pumping intermittently, the desirable force main velocity would be 3.5 to 5 ft/sec.
RE: Check valve in Pumped SS line
What is 'small'?
To bimr: Agree with your answer, and within theese limits a ball check valve should perform OK.
If you have a pump with soft start and stop a swing check valve with full open port and spring loaded type (spring outside valve body) will perform better, no hammering under varying load, but cost more.