A Presentation By Western Oil Filtration, Inc. Oil Varnish A Presentation By Western Oil Filtration, Inc.

What is Varnish? Varnish is a thin insoluble film deposit Hard, oil insoluble deposits on wetted surfaces Forms on fluid-wetted surfaces inside a turbine or other lube system Initially a gold/tan color Building to a darker gum-like layer Eventually develops into a hard lacquer like material Sludge (often found in oil tanks) Sub micron particles (<1um) Film formed due to insolubility in oil Machinerylubrication.com/read/29033

The Varnish Cycle Next Slide has video http://info.hyprofiltration.com/blog/bid/351084/Turbine-Lube-Oil-Varnish-and-Removal-Strategies-Part-3-of-4

Insoluble to Soluble Varnish Potential Video Click the Play Button to Watch Video ** Note how as temperature rises as shown with thermometer, varnish dissolves into solution changing the oil from cloudy to transparent.

Varnish Deposit

Causes of Varnish Oxidation Thermal Degradation Filter-Related Electrostatic Discharge Micro-Dieseling Chemical Contamination

Causes of Oxidation Acceleration When additives are depleted, the oxidation process is greatly accelerated. Water Aeration Wear metal particles such as iron and copper act as catalysts to speed up this process. Chemical contamination and mixing oils.

Oxidation – Inhibitor Additives Two Common Categories of Additives Hindered Phenols More suited for lower temperatures Aromatic Amines Perform better at higher temperatures A varnish test will require a new sample of oil to compare new additives vs. the current additive state of the oil. Machinerylubrication.com/read/29033 ----- Meeting Notes (8/28/14 12:51) ----- A Varnish tes will require a new sample of oil so be able to compare new additives vs. current state of equipment oil.

Sources Of Heat Leading To Varnish Production Insufficient cooling or high oil temperatures: Rule of thumb – With every additional 10 degrees C (18 degrees F) the rate of oxidation doubles (Arrhenius Rate Rule). Micro-dieseling – compression or collapse of small bubbles in the oil, causing heat. Filter-related or other electrostatic discharge.

Electrostatic Discharge

Electrostatic Discharge Is accelerated by high pressures and flows Caused by spark discharges with surface temps of above 10,000 degrees C Common with High Efficiency Synthetic Media and high oil flow. ----- Meeting Notes (8/28/14 12:51) ----- Finish and move order of slide

Electrostatic Discharge Video Turn up sound on your computer. Click photo to begin video.

Varnish Testing Primary Tests (Examples from Insight Services) Most valued test is MPC or Membrane Patch Colorimetry Particle count and Ultra Centrifuge help establish quantity of small varnish semi-solids ----- Meeting Notes (8/28/14 12:51) ----- have sample to pass around for threfernece

Varnish Testing Additional Useful Tests Ruler test compares active additives in the sample with active additive in virgin oil. FTIR is a test of the base stock degradation, oxidation and additive depletion in the oil, through trending. Acid increases with varnish production. Water is one of the most destructive contaminants.

The MPC Test Operating Principle Significance Once the sample is received by the lab, it is held for a specified time at a controlled temperature. Once the required time is reached a portion of the oil is mixed with a non-polar solvent and is passed through a .45 micron Millipore patch. Varnish material tends to be polar in nature, and not very soluble in the oil/solvent mixture. The insoluble material will be captured on the Millipore patch. Varnish tends to color the patch and by measuring the hue and intensity of the colored material deposited on the patch a general characterization can be made about the level of varnish in the system. Significance By monitoring the level of insolubles present in the lube oil, informed decisions can be made regarding the implementation of varnish mitigation technology and costly downtime avoided. Continued testing once varnish mitigation has been implemented can be used to help evaluate the effectiveness of the technology in use.

The MPC Test Example by Insight Services.

Optical Particle Count / Pore Blockage Particle Count Difference Can be an indication of insoluble degradation products present in the oil sample. Operating Principle Particulate contamination is tested using two methods, optical and pore blockage. Optical particle count passes the oil through a beam of light. Anything in the oil which interrupts the beam is counted as a particle. This method will count soft (varnish) particles. Pore blockage particle count passes the oil through a calibrated mesh screen which captures only hard particulates. A significant difference in the two results may be due to the presence of water, soft contaminants or insolubles. Significance By monitoring the level of insolubles present in the lube oil informed decisions can be made regarding the implementation of varnish mitigation technology and costly downtime due to varnish related issues can be avoided.

Optical Particle Count / Pore Blockage Particle Count Difference By measuring all particles and then removing only the hard particles with these two tests, a value of soft material or varnish material may be estimated.

The Ultra Centrifuge Test Measures the level of insoluble degradation products present in the oil sample. Operating Principle A portion of the oil is spun in an ultra centrifuge at 17,000 rpm for a specified time. Varnish molecules tend to be large, and have a higher molecular weight than oil molecules. These large molecules are forced to the bottom of the centrifuge tube where they form a solid deposit.  The amount of material deposited is compared to an established rating scale. The larger the deposit, the more likely the system is to experience varnish related issues. Significance By monitoring the level of insolubles present in the lube oil, informed decisions can be made regarding the implementation of varnish mitigation technology. This can help avoid costly downtime due to varnish related issues. Continued testing once varnish mitigation has been implemented can be used to help evaluate the effectiveness of the technology in use.

The Ultra Centrifuge Test Example by Insight Services

What Have You Seen??

Varnish Removal

Varnish Removal 2 Steps 1 - Depth Media 2 - Resin Beads Kidney Loop with Equipment in Operation at Temperature. Removes dissolved varnish potential from oil. Turbine Offline – Filter oil at 70o F removing condensed varnish potential from oil. (Quick Start)

Varnish Removal

Scavenging / Adsorption Varnish Removal Scavenging / Adsorption Soluble Varnish kept at low concentration Normal Operating Temp (High concentration varnish potential) Varnish removal (Low concentration varnish potential) Using varnish removal equipment, most oil will dissolve varnish deposits when low soluble varnish concentrations (varnish potential) are maintained.

Scavenging / Adsorption Varnish Removal Scavenging / Adsorption (High concentration varnish potential) (Low concentration varnish potential) Varnish potential is removed as it attaches to resin beads within the varnish removal system. Existing oil is used to remove varnish from the entire system while in operation. Once completed, oil can often remain in use depending on additive and other conditions.

www.westernoilfiltration.com or www.wofi.biz P.O. Box 1027 West Jordan, UT 84084 Sales & Service: (385) 204-6601 Office: (385) 215-9106 www.westernoilfiltration.com or www.wofi.biz