pump speck for nigative to positive pressure
pump speck for nigative to positive pressure
(OP)
Gents,
i am trying to select a pump which can operate from nigative suction pressure to positive suction pressure. I know the range is wide but it is our process requirnments? a part from self priming pump, is ther any alternativs?
upm
i am trying to select a pump which can operate from nigative suction pressure to positive suction pressure. I know the range is wide but it is our process requirnments? a part from self priming pump, is ther any alternativs?
upm





RE: pump speck for nigative to positive pressure
Other options
1. Use two pumps
2. Use positive displacement pumps
Regards,
RE: pump speck for nigative to positive pressure
RE: pump speck for nigative to positive pressure
thanks alot for the hints,the process folks have specified the parameters as:
flow (t/h) : 3 to 17
suction pressure: vacuum(-0.3barg) to positive (0.5 barg)
LP steam condensate (dinsity is about 1000 kg/m3)
discharge press. 3.5 to 4.5 barg
i know the range is too wide nut i need to select the optimum. Currently we are dumping the water and i have installed a temporary single stage air operated diaphragm pump and it works fine. however, the diaphragms are getting raptured every often once pumpming vacuum
upm
RE: pump speck for nigative to positive pressure
http://www.armstrong-intl.com/products/condpumps/cp.php3
http://www.spiraxsarco.com/assets/uploads/PDFs/sb/P136_01.PDF
Why is it that suction pressure (or is it condensate pressure) is varying from -0.3 bar g to 0.5 bar g? Am I missing something?
Regards,
RE: pump speck for nigative to positive pressure
If your flow and pressures can all vary independently, then you'll need to design the pump to handle from -0.3 barg suction to 4.5 barg discharge at 17 t/hr flow (plus any design allowances you might need). The control system and recirculation system would have to then be designed for the other possible high suction pressure, low discharge pressure, low flow operating conditions.
As Quark suggested, you might also want to look at a self powered condensate pump. I've put one of these in and it worked just as it was supposed to. It's bound to be a lot cheaper than a pump system, especially for these flows. You need to have a source of pressure to push the condensate out during the discharge cycle higher than the 4.5 barg condensate pressure.
Is the range of suction pressures due to the load or cleaniness of an upstream heat exchanger?
RE: pump speck for nigative to positive pressure
you are exactly correct,h/e is upstream the new pump and based on the load the suction pressure varies.
what type pf pumps dod you install? brand name and address
upm
RE: pump speck for nigative to positive pressure
Someone else here is bound to have a more up to date recommendation. Several manufacturers make these, I'd talk to them, get some references and talk to the users about their experience in services similar to yours.
Armstrong also makes self powered pumping traps. There are bound to be lots more companies.
RE: pump speck for nigative to positive pressure
upm
RE: pump speck for nigative to positive pressure
RE: pump speck for nigative to positive pressure
One of the things I love about this site is the users' expert command of spelling and English - eg, "nigative" pressure and diaphrams that are "raptured".
Smile of the day :)