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Oil Feedstock => Oil coarse filtering, settling, drying and storage => Topic started by: photoman290 on February 15, 2013, 03:48:20 PM

Title: gear pump for centrifuge.
Post by: photoman290 on February 15, 2013, 03:48:20 PM
after digging around  i have found a gear pump on an old oil burner, the gun type. the pump says 8-15 bar,and on the plate on the burner it says "oil consumption 6 square mm /sec" is this likely to be any good to run a centrifuge? the burner is 60 kw so i assume that  means it uses quite  a lot of oil. motor  runs at 2750 rpm. anyone  got i any ideas. be very handy if is any good as it is compact and low power. 90 watts.
Title: Re: gear pump for centrifuge.
Post by: Jamesrl on February 15, 2013, 03:57:26 PM
You'll need approx 7 - 8 ltr/min flow rate at 7bar.
Title: Re: gear pump for centrifuge.
Post by: photoman290 on February 15, 2013, 04:00:43 PM
hi jim how do i convert 6 square mm /sec into litres a minute? i know mm to cc is multiply by 0.1 but that hasn't got me very far.
Title: Re: gear pump for centrifuge.
Post by: julianf on February 15, 2013, 04:36:38 PM
   
1 millilitre = 0.001 litres
1 cubic centimetre = 0.001 litres
1mm³ = 0.000001 litres

6mm³ = 0.000006 litres (second, in your case)


0.000006 x 60 (seconds) = 0.00036 lpm



Title: Re: gear pump for centrifuge.
Post by: julianf on February 15, 2013, 04:38:29 PM
7.5 / 0.00036 = 20833

which seems rather high, so i guess i might have made an error!
Title: Re: gear pump for centrifuge.
Post by: julianf on February 15, 2013, 04:43:49 PM
0.000006 x 60 (seconds) = 0.00036 lpm


Are you sure you have read the markings off the pump correctly?

0.00036 lpm = 0.0216 lph

which does not add up, as there is no way you can run a 60kw boiler on that sort of consumption!
Title: Re: gear pump for centrifuge.
Post by: photoman290 on February 15, 2013, 06:11:45 PM
just calulated it from first principles. 60 kw rating so assuming,maybe wrongly 60kw/h works out at 204000 btu. ione US gallon of kero produces 140000 BTU so 204000 BTU is about 6 litres an hour? still seems low. the plate says
riello  type 444 t 50.
 the number i quoted before may be the viscosity. it says before the number max viscosity @20 degrees C  6 square mm/sec( 1.5degrees E)

there is a picture of a jet with 2.3/ 5kg/h
then under that 28/60kw
that is everything on the plate.

so i assume from that it will use between 2.3 and 5kg an hour.? i make that about 6 litres an hour. not enough to run a centrifuge then. to answer my own question.
 
Title: Re: gear pump for centrifuge.
Post by: julesandtash on February 15, 2013, 07:32:33 PM
5Kg per hour sounds about right - my 35KW burner has a 0.85 US Gallons/hr nozzle (which is around 3.2 litres per hr)

Assuming a density of 0.8Kg/litre for kerosene that equates to 2.56Kg per hr.

However, square mm/sec appears to be a unit of kinematic viscosity as per here
http://www.unitconversion.org/viscosity-kinematic/square-millimeter-per-second-conversion.html
Title: Re: gear pump for centrifuge.
Post by: nathanrobo on February 15, 2013, 10:40:22 PM
Could you run it more slowly?
Title: Re: gear pump for centrifuge.
Post by: 1958steveflying on February 15, 2013, 10:44:20 PM
Could you run it more slowly?

you must of missed it mate....

so i assume from that it will use between 2.3 and 5kg an hour.? i make that about 6 litres an hour. not enough to run a centrifuge then. to answer my own question.
Title: Re: gear pump for centrifuge.
Post by: nathanrobo on February 15, 2013, 10:55:56 PM
Could you run it more slowly?

you must of missed it mate....

so i assume from that it will use between 2.3 and 5kg an hour.? i make that about 6 litres an hour. not enough to run a centrifuge then. to answer my own question.

Me not reading the complete post properly. 

Assuming a smaller fuge 200cc or 250cc bowl, the flow requirement will be about 4.2 - 4.6 LPM (depending on jets).  I work on the basis that you want a pump that's a bit more flow than the fuge (viscosity will affect pressure and flow - really low viscosity - for example bio, can result in a bit of slippage between gears, resulting in slightly lower pressure and flow).  I use a 3cc per rev pump mated to a 2645 rpm.  This means a bit on bypass with the smallest four sized fuges and just about enough to drive a 500cc.  For bigger fuges I go up to a 5cc per rev. 

Hope that's some use. 
Title: Re: gear pump for centrifuge.
Post by: photoman290 on February 15, 2013, 11:35:28 PM
hi nathan, got that bit ok. just wasn't sure of the  rating of the pump i found. i need something a lot bigger. back to the power steering pump idea then.
Title: Re: gear pump for centrifuge.
Post by: nathanrobo on February 16, 2013, 11:41:15 AM
Motor wise a smaller fuge can be driven by 0.37kw or 1/2 hp.  Less than this tends to struggle with the load at above 6 bar.  Not sure how that goes with other pumps.  But all being equal it should be similar.