Check valve with perforated disc
Check valve with perforated disc
(OP)
Hello,
I am currently working on a water pumping station with an overall capacity of 2200 l/s (nearly 8000 m3/h), the latter is delivering water to a storage tank. The scope of the project includs installing surge tanks to protect the system from water hammer effects. According to the client specification, a check valve ,with a perforated disc, must be installed in the line entering the surge tank. My inquiry is as follows:
The surge tanks protects the piping system along with other equipements by letting the water flows in and out of it. So, it would be pointless to install a check valve in the piping that feeds it, So:
- What special featers does the perforeted disc of a check valve has ?
- How could we set the specification of the holes to be perforated on the disc (size, number and arrangement)
- Should the check valve be installed towards the surge tank or is it in the opposit direction ?
This the first time I encouter such design, so all informations, recommendations and ideas will be very helpful
Thank you
I am currently working on a water pumping station with an overall capacity of 2200 l/s (nearly 8000 m3/h), the latter is delivering water to a storage tank. The scope of the project includs installing surge tanks to protect the system from water hammer effects. According to the client specification, a check valve ,with a perforated disc, must be installed in the line entering the surge tank. My inquiry is as follows:
The surge tanks protects the piping system along with other equipements by letting the water flows in and out of it. So, it would be pointless to install a check valve in the piping that feeds it, So:
- What special featers does the perforeted disc of a check valve has ?
- How could we set the specification of the holes to be perforated on the disc (size, number and arrangement)
- Should the check valve be installed towards the surge tank or is it in the opposit direction ?
This the first time I encouter such design, so all informations, recommendations and ideas will be very helpful
Thank you





RE: Check valve with perforated disc
Perforated check valves are used when you want a simple system which allows flow in one direction with minimal pressure drop but reduced flow in the reverse direction with a lot of pressure drop.
Sizing of the hole is basically an orifice calculation - you know pressure one side, pressure the other and the hole size dictates the flow.
I can only think that where you have a pressurised surge tank / accumulator you need unrestricted flow into the tank to relieve the surge flow, but you don't want unrestricted flow back out creating another surge, but you do need to slowly release the volume / pressure in the surge vessel. This only really applies to pressurised vessels. the key word is slowly release the surge volume.
All depends whether your surge is at the reception end ( usually a positive surge pressure) or at the pump end ( usually a negative surge). You tell me I don't know.
Doing this with a check valve is not great engineering as check valves fail regularly but I guess it depends how often you get or anticipate surge events occurring. If its every time you start / stop then you need something more robust, if its an accidental case once every 10 years then it's a different case.
Draw or sketch your system so we can understand where the tanks are, what types of tanks and where this check valve "must be" installed.
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
RE: Check valve with perforated disc
RE: Check valve with perforated disc
As it is indicated on the sketch, surge tanks are at the discharge line of the pumps.
I hope this helps clarfying the situation.
RE: Check valve with perforated disc
http://www.swawwa.org/ace14presentations/Surge_Sup...
" By partially limiting or blocking the action of the check valve, either through by-passing the valve with a smaller diameter parallel line or by perforating the valve itself with a relief-valve-like opening, a portion of the high pressure fluid can be passed back to the relatively lower pressure side, thus bringing the two sides into closer hydraulic communication, and limiting the upsurge on the downstream side."
https://digital.library.adelaide.edu.au/dspace/bit...
It is not typical practice use perforated check valves where I practice. It would be preferred to design the system to eliminate the water hammer using techniques such as soft start controls, quick closing check valves, etc.
RE: Check valve with perforated disc
http://www2.emersonprocess.com/siteadmincenter/PM%...
http://www.spxflow.com/en/mj-valve/pd-mp-ctlvalve-...
RE: Check valve with perforated disc
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
RE: Check valve with perforated disc
RE: Check valve with perforated disc
For reasons we don't know the client seems to want one. Probably in error, but we don't know.
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
RE: Check valve with perforated disc
RE: Check valve with perforated disc
A damped check valve would work just as well.
Presume this check valve is on a horizontal piping run, else there would be flow turndown issues with a dual plate check valve. Would guess a 3mm hole on one or both plates would be okay.
The Daniel surge relief valves suggested may act as ultimate protection in case there is a risk of plugging on one or both of these perforations.
Guess the only reason for this perforated check valve would be to minimise the hazard from a reverse flow from the pressurised (or elevated) large surge storage tank(s). What is the total volume of these surge tanks, and at what pressure (or elevation relative to pump grade) are they?