Closed impeller / open impeller

[julianf]

My interest has been sparked from the comments on simonallen's thread -


My first pumps were those Leo ones (the tam look-a-likes that were cheap on ebay that time).
They were open impeller.  Only once did i ever have to unblock one, and that was my own fault (sucking in lumpy methoxide)


My second pumps were multistage grundfoss ones.  They were good pumps (even the paint was bio-proof, and no capacitor housing issues!) however, they were closed impeller, and would get blocked by bits that would go through my pre-filtering without bother.  And then they were a pain to clean out.

My third pumps, when i get around to it, are the 110lpm jgs600 ones.  I need to check if theyre open or closed impeller (anyone know for sure?) but, from my previous experience, im hoping open...


Anyone else have comments?  From my experience, it would seem that open impeller is the way to go for biodiesel processors every time.

[Tony]

I don't think you can get quite so much thrust from an open impeller, I think the high pressure multistagers (which I love) are all closed impeller.  But they (Calpeda MXHM203 - I've got four of these) are also designed to be easily dismantled for cleaning if necessary.  It is bit of an extra burden but I wouldn't swap them for anything else.

[Jamesrl]

The jgs 110 pumps have closed impellers.

The leos have periferal turbine impellers and work on a diferent principle.

[nigelb]

What is meant by open and closed impellors?

[Jamesrl]

What is meant by open and closed impellors?

An open impeller has only one disc with spiral blades facing the inlet, like a turbo.

Closed has two discs with the blades between an a hole at the centre of the disc facing the inlet.

[nigelb]

So my Lowara would be closed impellor. Thanks for that Pops.

[julesandtash]

JGS110s are closed impeller

My Calpeda CM22E is open impeller and still moves 110lpm. I know it is open impeller as I took it apart and had a look. The spec for them states that they will pump fluids with solids up to 4mm and performance on my plant is as good as the JGS110 one I borrowed from NigelB

Here is a link to them https://www.colglo.co.uk/product.php?product=CALPCM22E

I hasten to add I did not pay £261+vat for mine - I got it for £35 brand new from eBay thanks to the pumpophiles thread.

[nigelb]

I hasten to add I did not pay £261+vat for mine - I got it for £35 brand new from eBay thanks to the pumpophiles thread.

It was the pumpophiles that put me onto my Lowara...bless them for they know what good they do for the community.

[Julian]

"bless them"?

... you don't know how hard life is as a pumpophile.

I've just had to buy my fourth Mono!

[Jamesrl]

"bless them"?

... you don't know how hard life is as a pumpophile.

I've just had to buy my fourth Mono!

You mean 3d printing is NOT the Antidote?

Have you thought about breeding the little darlings?