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Hi,

I am looking to address varnish issues that are appearing on 2 of my steam turbine units, in our main turbine oil.

I have gotten information about 2 alternatives:
a cellulose based filters and electrostatic based filters, both operating in a fixed, kidney-loop configuration.

I was wondering if anyone one has any experience or information regarding either of the two options.

Thanks
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There are several posts under industrial lubrication and oil analysis links on this website dealing with varnish in steam turbines, about 2/3 down on both links. Discussions involve combining antioxidant package/varnish potential monitoring techniques (to prevent varnish)as well as success of different filtration techniques in removing varnish once it has started to accumulate. ASTM has workgroup to develop a standardized method for varnish potential
amy w,
Both options could be effective. Bare in mind that the amount of varnish particles in oil depends on oil’s solvency characteristic; higher solvency – less varnish particles and vice versa. Also, temperature is a factor; warmer oil – higher solvency. Small presence of water in oil does not affect performance of a low-flow cellulose fiber filters; actually they would absorb it and keep the oil dry. On the other hand, water in oil (better say moisture) decreases the efficiency of electrostatic filters, unless they include a cellulose fiber in its configuration (I have seen such combination). Considering this situations, in my opinion, a low-flow 3-micron cellulose fiber filters are better suited (and are cheaper) in conditions where the oil temp is bellow 75 C. This is due to coagulation of varnish particles phenomena occurring at lower temp. Electrostatics filters are the answer at higher temp, where they are more effective of capturing individual varnish particles.
Amy,

Please look at www.oilkleen.com for some very good information and the solution to varnish related issues.

However, I must disagree with John on the following statement: "Electrostatics filters are the answer at higher temp, where they are more effective of capturing individual varnish particles...." At OILKLEEN we have proven that our systems actually remove more insolube oxidation by-products at lower temperatures. Temperature is a huge factor in removing varnish. At higher temps oxidation becomes soluble and thus will not be removed, and lower temps the free-radical oxidation becomes insoluble and can be removed by an electrostatic oil cleaner.

Example:
Basically varnish is created from oxidation of the oil. Heat and water are bad. There are different ways to measure the levels of oxidation. One is the QSA, or colorimetric patch test. This will measure the insoluble oxidation by-products and basically anything else in the oil that is insoluble. It's a scale from 0-100, and let's say you performed a colorimetric patch test on your oil at 140 degrees F and for easy math your patch yields a 24 as your result. Throw the remaining sample in the freezer for 2 hours and run the same sample in colorimetrics and you might have an 80 now. This test only measures insolubles in the oil, and is very effective in doing so. Whats important is that electrostatic oil cleaners can only remove insoluble foreign material and is why we don't damage the additive packages. EOC systems can remove alot more contamination at cooler temps and thats why we build a system with a chiller.

This example is important because only an electrostatic oil cleaner can clean to the 0.001 micron size, or the size of a molecule. This happens because a molecule will take an electric charge just like a large piece of dirt. It doesn't know the diffrence.

Before you purchase any unit please take a look at some of the case studies on the OILKLEEN systems. We pride ourselves on the performance of our machines and would put our technology up against any other in the world.

Thank you,

Paul Jarvis
OILKLEEN INTERNATIONAL, Inc.
President
480.556.1520
480.650.8711
www.oilkleen.com
quote:
Originally posted by OILKLEEN:
...I must disagree with John on the following statement: "Electrostatics filters are the answer at higher temp, where they are more effective of capturing individual varnish particles...."


What I meant ws, if the oil is constantly at higher temp, then the electrostatic filters are more effective in capturing varnish particles than a cellulose fiber type filters. On the other hand, if the oil is cooled down below 75 degrees C (hopefully not in the freezing range) than the both technologies are comparatively effective (they both easier and effectively deal with agglomerated varnish particle due to cooler conditions). However, cellulose fiber filters are not only cheaper to buy and maintain, but, contrary to the electrostatic technology, they will take out reasonable amount of water out of the oil (condensation water). I may be wrong, but my statement is based on our personal experience with both technologies, being set side by side (hooked on two adjacent governor sumps), ran, and their efficiencies observed and documented with lab test data (both systems cleaned oil down to 13/12/10 (c) and maintained this level, which is satisfactory for hydroturbine application). Both systems were used off-line for filtering of governors’ R&O ISO 68 oil. Cost of units was the primary reason why we decided to buy cellulose fiber filters for our application. Things may be different if targeted cleanliness level is much lower. Again, I only tried IMHO to answer amy’s request
quote:
I was wondering if anyone one has any experience or information regarding either of the two options.
, and with no intent to use “wide brush stokes”. Also, I am not a dealer or rep of any product or company, including the ones discussed.
Thanks John for the honest reporting. I am not sure why everyone avoids using the name CC Jensen or CJC when it comes to describing the only cellulose technology (or electrostatic for that matter) with any actual results showing actual quantities of varnish material removed. The CJC elements have real data revealing that they are able to hold quantities between 8 and 15 pounds per element of varnish particles and they are not mechnically filtered out like dirt. Checkout the our website to see how the varnish is removed! CJC Canada
Ask the competition where does their varnish go and how much they actually remove or does it agglomerate and fall to the bottom of the tank? I also have several customers (now using CC Jensen) that have two brands of electrostatic units for sale - cheap.
To answer Harv's question:

"Ask the competition where does their varnish go and how much they actually remove or does it agglomerate and fall to the bottom of the tank?"...

Inside our tank we have a collection cartridge which has 16 electrostatic fields that the contaminated oil must pass through. Inside each of those fields we have a collection media. As the particles get charged by the 15,000 volts of field strength, those particles bond to the collection media through laws of physics. Since all the varnish and contamination particles actually bond to the media we have ahuge dirt holding capacity. Internal testing has shown we can hold 10-13 pounds of contamination inside our cartridges. If your familiar with powder coating, the contamination actually bonds to the collection media and then comes out when you change the cartridge.

So with our technology there is no agglomeration of particles.

There is alot of myths and bad marketing tactics in the industry now, and all I want to do is at least explain what happens with our technology and why it works so well.
ServoCon ALPHA
167 Expo Road
Fishersville, VA 22939
(T) 800-447-7747 (F) 540-337-4901
Website www.servoconalpha.com

Greetings,

AS the EHC system ages, varnish is deposited on the inner walls of the piping, valves, actuators and system components. The varnish is generally a very hard, tenacious deposit that is accumulated over time. Varnish can occur in oils that appear healthy and clean, with no visible signs for concern through normal oil analysis. It cannot be identified by the typical in-service turbine oil tests. Low total acid number (TAN), a low ISO particle count and a high RPVOT does not guarantee that the lubricant is immune from varnish. The varnish deposits that form on machine surfaces cause numerous operational issues by interfering with the reliable performance of the fluid and the machine’s mechanical movements. They can also contribute to wear and corrosion or simply just cling to surfaces.

Other potential problems include: restriction and sticking in moving mechanical parts such as servo or directional valves, servovalve failure, increased component wear due to varnish’s propensity to attract dirt and solid particle contaminants, loss of heat transfer in heat exchangers due to varnish’s insulation effect, catalytic deterioration of the lubricant, plugging of small oil flow orifices and oil strainers, increase of friction, heat and energy because varnish acts as a heat insulator, reduction in filter efficiency and potential filter plugging, damage to mechanical seals, increased maintenance costs due to cleanup and discard of oil.

FLUSHING, CHANGING FLUID AND ELECTROSTATIC PURIFICATION/ IONIC EXCHANGE FILTERING SYSTEMS WILL NOT REMOVE ALL VARNISHING, nor in any way will it help worn parts, such as cylinder piston rings that lead to internal leakage, another contributing factor to varnishing. The only way to remove the varnish from your system in conjunction with proper filtration, fluid monitoring and some of the above ideas is to remove the hydraulic controls such as the cylinders and servovalves from the turbine and have them disassembled, extensively cleaned, re-sealed, worn parts replaced, and machine honed to remove the baked in varnishing, a process that ServoCon ALPHA has perfected. This is normally done during an outage.

While ServoCon ALPHA is disassembling, inspecting, taking photos of as found parts, extensively cleaning, machine honing baked in varnish, replacing seals and worn parts, you should drain old fluid from turbine, thoroughly clean reservoir tank, flush hydraulic lines and hoses and install new filtered/test fluid. It is important to maintain the proper OEM filter recommendations after the units have been re-installed on steam turbine.

Respectfully,
Brian K. Supinger
Account Specialist
BUYER BEWARE
One of our plants has used an Oilkleen system before. The internals of the machine are plastic. I don't know of any other oil handling equipment that is made of plastic. Is this to lower cost? Regardless, the electrostatic filters warped from the high oil operating temperatures and several hundred gallons of oil were spilled. Other plants have also had spills using this equipment according to user forums.

Before you buy any oil conditioning equipment, make sure that it is manufactured with responsible materials of construction.
Thank you CC USER for the nice plug!

Our older patents did require high temp thermoplastics to insulate the electrostatic chamber.

However, I am proud to announce that OILKLEEN will be launching it's new OILKLEEN GREEN MACHEEN which is a completely new technology at the NORIA Lubrication Excellence show in Louisville, Ky.

The GREEN MACHEEN will use stainless steel tanks and will have the 16 elestrostatic fields perpendicular to the oil flow which we have had so much sucess with. No other company in the world will have 16 electrostatic fields that the oil must pass through and have the durability of stainless steel tanks.

I invite you CC User to come see our launch at the NORIA show and we look forward at OILKLEEN to continue to reasearch and devlop the worlds fastest and most efficeint electrostatic oil cleaner.
quote:
Originally posted by OILKLEEN:
Thank you CC USER for the nice plug!

Our older patents did require high temp thermoplastics to insulate the electrostatic chamber.

However, I am proud to announce that OILKLEEN will be launching it's new OILKLEEN GREEN MACHEEN which is a completely new technology at the NORIA Lubrication Excellence show in Louisville, Ky.

The GREEN MACHEEN will use stainless steel tanks and will have the 16 elestrostatic fields perpendicular to the oil flow which we have had so much sucess with. No other company in the world will have 16 electrostatic fields that the oil must pass through and have the durability of stainless steel tanks.

I invite you CC User to come see our launch at the NORIA show and we look forward at OILKLEEN to continue to reasearch and devlop the worlds fastest and most efficeint electrostatic oil cleaner.

Glad to hear it! What is the flow rate of this new setup, and how’s going to deal with water from oil?
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