Author Topic: making a centrifuge  (Read 11945 times)

M61hops

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making a centrifuge
« on: January 22, 2014, 10:05:23 PM »
Hi everybody!  I'm wanting to make a centrifuge for cleaning used oil and I was thinking of using an old cast iron brake drum from a car.  Can anybody tell me how to figure how much G force I'd have spinning a 12 inch brake drum at 3,480 RPM and if the average brake drum can safely be spun that fast?  I'd think a brake drum would take that since they have to withstand the force of the brake shoes pushing on them.  I'd rather not spend the money for an aluminum bowl.  I was going to mount the bowl on the shaft of a 2 pole 60 cycle motor and use an old pressure cooker for the housing.  I thought I could make a top cap for the drum out of either steel or aluminum plate.  I've got the pressure cooker and a couple of brake drums to choose from.  I already have a 1/2 HP motor but I'm not yet sure it's designed to operate in a vertical position.  Does that seem like enough horsepower?  If I need to get another motor I could go bigger.  Or how about belt drive for speed options?  What do you folks think?  Thanks for any ideas!             Leland
I pray everyday giving thanks that I have one of the "fun" mental disorders!

millman56

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Re: making a centrifuge
« Reply #1 on: January 22, 2014, 10:58:30 PM »
 Leland,   the  g force for that speed is over 2000 g .  Thats 2000 X the weight of the drum and oil contained within trying to accelerate into space at 20.2395 kilometres per second per second,   just make sure you run it up remotely and  contained in a blast shelter ;D 

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buickanddeere

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Re: making a centrifuge
« Reply #2 on: January 22, 2014, 11:45:33 PM »
  Old working dairy cream separators are cheaper than a home build centrifugal bomb.

millman56

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Re: making a centrifuge
« Reply #3 on: January 23, 2014, 12:12:12 AM »
Several  truck manufacturers fitted oil  powered  centrifuges,  if you aquired one all you would need would be a suitable hyd pump,a suitable container, a way of heating the oil  and a some connecting pipework.

Mark.

Rom

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Re: making a centrifuge
« Reply #4 on: January 23, 2014, 04:33:49 PM »
I use a centrifuge from simplecentrifuge.com. They sell the bowl by itself if you are interested in building your own. Would get a more efficient design for separation of the gunk from the good material this way. Mind you the bowl is 650$

I ended up buying the complete rig a few years ago to save me the hassle of finding the materials out here, and it is the best thing I bought besides my lister me thinks.

Rom

M61hops

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Re: making a centrifuge
« Reply #5 on: January 25, 2014, 01:24:15 PM »
Thanks for the feedback guys.  I haven't been able to find any published info on how fast a brake drum can be safely spun.  2,000G's sounds like a nice round number for cleaning used motor oil though  ;D !  Does anybody know of a valid rule of thumb as to what the minimum G's would be to spin water and the common crap out of WMO?  Buying a new turn key unit is not going to happen unless I hit the Lotto but if I make one out of parts I can scrounge it needs to work well enough to make it worth doing.  Hey Rom what is the diameter of the bowl and how fast does it spin?  What do you run through it and does it do a good job removing water?  I'm hoping I can build something that works well and keep the cost down to a few hundred $ at most.  Thanks again guys!                Leland
I pray everyday giving thanks that I have one of the "fun" mental disorders!

dieselgman

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Re: making a centrifuge
« Reply #6 on: January 25, 2014, 05:08:09 PM »
If I was going to do this on a DIY basis, I would start with buying a used industrial unit from the ship-breakers in India. You should be able to get one within a budget of a few hundred dollars. I have seen numbers like $500 for a substantial size unit in working condition.

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buickanddeere

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Re: making a centrifuge
« Reply #7 on: January 25, 2014, 06:06:05 PM »
Thanks for the feedback guys.  I haven't been able to find any published info on how fast a brake drum can be safely spun.  2,000G's sounds like a nice round number for cleaning used motor oil though  ;D !  Does anybody know of a valid rule of thumb as to what the minimum G's would be to spin water and the common crap out of WMO?  Buying a new turn key unit is not going to happen unless I hit the Lotto but if I make one out of parts I can scrounge it needs to work well enough to make it worth doing.  Hey Rom what is the diameter of the bowl and how fast does it spin?  What do you run through it and does it do a good job removing water?  I'm hoping I can build something that works well and keep the cost down to a few hundred $ at most.  Thanks again guys!                Leland

I guess you never took my advice to heart and looked for a $50 cream separator at a farm sale or in the classified ads.

listard-jp2

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Re: making a centrifuge
« Reply #8 on: January 25, 2014, 08:27:11 PM »
You might like to take a look at this offering from India:

http://www.indiamart.com/centrifugefilters/centrifugal-oil-cleaners.html

n2toh

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Re: making a centrifuge
« Reply #9 on: February 02, 2014, 08:30:18 AM »
Why not have a look at the products from this company? they have several different models including motor and oil driven centrifuge.

http://www.pabiodieselsupply.com/
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M61hops

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Re: making a centrifuge
« Reply #10 on: February 07, 2014, 03:16:42 PM »
Hi again everybody!  Turns out there was a good thread about centrifuges over on the micro co-gen site!  I'll be keeping my eye out for a torque converter that has the right shape and/or thinking of some way to find out how to safely explode a brake drum.  It's not likely I'd run across a cream separator or factory built centrifuge around where I live and there is not even much scrap metal in my small town.  If anybody knows of a good deal on something in northern California please let me know.  For me it's a one way drive of about 50 miles to a you pull junk yard and 100 miles to a scrap metal yard so the re-purposing of car parts has a certain appeal to me.  When I get something set up I'll post photos but right now I'm still in the scrounge parts stage!      Leland
I pray everyday giving thanks that I have one of the "fun" mental disorders!