Would turning a pump on and off repeatedly damage it?

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rwooduk
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Hi, I need a liquid pump that can deliver BOTH smooth flow and pulsed flow, I've looked at:

Normal liquid pumps
Metering pumps
peristaltic pumps
Liquid respiration pumps
Centrifugal blood pumps

The latter two provide pulsed flow, but I'm struggling to find a pump that can deliver both continuous (0 - ~800mL/min) AND pulsed flow.

So what if I somehow attach a continuous flow pump to a square wave power output? Or have a timer or something that turns it on for say 10 seconds then cuts the power for 2 seconds and then turns the power back on again?

I could use a basic liquid pump, but it's likely we will be working with something like this:

https://www.coleparmer.co.uk/i/mn/7316033

My question is, would flicking power on and off damage the electronics of the pump? And the plug will just plug straight into the mains, how would I get a square wave to power the pump?

Thanks for any advice on this.
 
on Phys.org
Nidum said:
Solenoid valves .

I did not know the name, thanks!
 
Yep, to accomplish what you want to do start with a pump that can deliver smooth delivery and use a control system of valves to achieve the pulsed flow. A centrifugal would work well but it does have a high shear rate. Multiple positive displacement elements can produce a pretty smooth flow without too much shear. Look at rotating lobe pumps, for example.
 
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rwooduk said:
My question is, would flicking power on and off damage the electronics of the pump? And the plug will just plug straight into the mains, how would I get a square wave to power the pump?
Usually, when electronics are turned on and off, the current spikes so there is a momentary stress on the electronics. If one, 'flickers' the power, I would imagine there is some thermal or mechanical fatigue. Mechanical fatigue of pump bearings and shaft are also a concern.
 
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