which is a best method for filtration of hydraulic oils ? why ?
a. Centrifuging
b. Micro filtration cartridges
c. Electrostatic cleaner
d. Whether reclaimation of hydraulic oil is possible at site.

Dear Hiten
We offer On site Hydraulic / Lub. Oil Condition Monitoring with Laser Particle Counter and Cleaning it up to required International Oil Cleanliness level Standards like NAS / ISO, with imported Filtration Filtration Trolley and Laser Particle Counter. Pumping Capacity is 3000 Ltrs. / Hr. and entire Process is Automatic. For Further information Please contact me at zankruti@mtnl.net.in ; hymatservices@yahoo.co.in

V.S.Dave

The best way for filtration of hydraulic oils is microfiltration! But you have to use a real microfiltering system. EUROPAFILTER takes particles down to 0,1 micron and all kinds of water. It's made of woodpulp and take both particles and water in the same operation.
98 % of the particles are below 5 micron and will not be counted when using ISO4406 or NAS1638. Mostly of the filters on the market don't take particles below 3 micron. But even that, no one comes down to ISO4406 class 14/7 or so. EUROPAFILTER goes down to ISO4406 class 8/6 and water to under 50 ppm.

I can filter oil down to ISO4406 class 7/4 using a roll of toilet paper. You just keep on pooring the one liter of oil through a million times and the oil is particle free.

Please stop using these boards as a marketing place.

HITEN: I think you will find some discution about the subject here:
http://forums.noria.com/eve/forums/a/tpc/f/938604995/m/359104782
http://forums.noria.com/eve/forums/a/tpc/f/938604995/m/404108932

Wonderful response Mr. Hughes!

Mr. Hitten,

All of the methods you mention in your post are all valid: a-c. Point d is a completely different topic all together, but certainly possible. Reclaiming fluids on site is a choice of economics and usually reserved for companies who use large quantities of a particular fluid. However answers like this one aren't that easy and topic like reclaiming oil require a thorough investigation.

Traditionally micro filtration is considered the industry standard and more importantly in the minds of the disposable filter element manufacturers THE best way to filter hydraulic oils.

Electrostatic cleaners and Centrifuges also have their place but I would suggest that you first find at all of the particular needs of your process, (not in any particular order), such as the cleanliness requirements of your components. Current schedule outages vs forced outages of these components. Component type and life expectancy, lost manufacturing or operating time.

Just going thro all the replies of the forum we are tending to be " Pennywise and pound foolish" in the sense that we don't really look at the criticality of the application and critical applications should be designed with suitable filteration system but we are trying to find out ways to improving the oil cleanliness by not sourcing quality hydraulic oils.

Centrifuges and cartridge filtration both have their place. As Crag said, economics is the keyword. Centrifuges provide a high level of filtration but are usually on the pricey side. Cartridge filtration can provide excellent results as well when utilized properly. What you need to ask yourself is: how soon am I going to get payback on the system? What am I trying to accomplish? Why? What are your current costs with your present method of operation? Email me if you care to discuss this in further detail.

Hiten,
I know of a service offered by Shell. They have the ability to do on-site vacuum dehydration and filtration. The service is able to test on-site for water levels and ISO cleanliness. Big money saver! Allows for reuse of oil that would be disposed of and replaced.
LD

We are manufacturers located in China.We have technology applicable to used lube oil purification and filtration.

website: nicolas.********

This is a forum for techy help , you really need to get the parameters you deisre as fitleration is huge ocean, one needs to know what you want, what oil you want to filter , what is the contamination level , what application you want to put your fitlered oil to and so on...

Technology in poit B is the safest for hydraulic oils to the best of my understanding if you are a user oil and not an oil expert , as in centrifuge and electrostatic filteration tecniques you might need to chk for changes in additive levels - and thats some analysis.

I think I'll go for micro filtration, which means either this will be offline filtration of by-pass filter with a higher efficiency and beta rating of 200 or more. Why ?

In the process of using centrifuge you need to drain the oil and place it in a centrifuge equipment and then test the oil for a go or no go and transfering it back to your hydraulic equipment. This means that your machine must be down, however and offline filtration or by-pass must be performed when your equipment is running which means that there is no downtime in performing the cleaning.

Electrostatic filtration does not affect soluble additives. It can remove insoluble additives.

We recently tested our newest BCA machine in an injection molding hydraulics application. Even though the ISO numbers were great and the oil was just a few years old, the oil was full of submicron contaminants. we started with a gravimetric of 240mg/100ml. After about 2 weeks of electrostatic filtering the grav. read 6mg/100ml. Electrostatic filtering was clearly superior to the bypass micro-filter they had in the system.

The problem really comes down to costs of the oil and the problems you are seeing in maintenance of the hydraulic system. If you have a small quantity of oil and very little in hydraulic problems, a filter is the right choice. If you have a lot of sumps, and serious hydraulic component problems, electrostatics are worth the expense. For more information about the test results, email me or call.