Masterflex Peristalic Pump Issues

Hi maizeegirl4,

Any temp difference between fill point and measuring point? Could be density difference causing the discrepancy.

Just a thought,

Mike

Any thoughts on options for what people are using instead?

You can get diaphragm pumps, you can accurately measure the dose per stroke..some of the more expensive ones have adjustable stroke.

Seko, Prominent, Grunfos...loads of people do 'em. More expensive than a peristaltic..but much longer lasting/less maintenance.(Noisier too )

Just do a search for diaphragm metering pump, or some of the above names.

Del

Depending on product viscosity and consistency, you could use a small gear pump or progressive cavity pump. Both are good as dosing pumps.

I think you are just asking for too much accuracy from a peristaltic.

There are so many variables, even a bit of tension on the tube can change the delivery (if the tubes extand out of the pump head and are not anchored).
Does each pump have it's own power supply and is the supply over-rated by a good margin so it doesn't sag.

Is the motor/gearbox geared down nicely eg plenty of revs on the motor for low revs on the output shaft.

What is the wall/bore size of the tube and what material?

You may be able to improve things a bit.

Del

Del

Any information about what people are using or doing instead for product fills?

Just to make sure ... you pump is connected to a controller correct? If so the pump motor(rpm) is has a feed back from an opto coupler on the shaft near the end that has the brushes. make sure the slotted ring the coupler is counting, the holes are not plugged . We had some solution get in to ours and the speed went crazy. The RPMs will show good but the pump will speed up and slow down. And be enough to throw it off a bit.

I agre with the previos reply about inside diameter of the hose. Furthermore, I woulod reccomend using a Tygon hose. The longevity is decreased but because it is a softer compound, more accurate results are possible. Just my cents.

This subject pump gives about 521ml instead of original 531ml, which amount to about 1.8%.

Like Del the cat feels, this is too much of accuracy from a peristaltic type.

Any ideas about what people are using instead?