March / April 2016 NLGI Spokesman

NLGI

SPOKESMAN

Serving the Grease Industry Since 1933 – VOL. 80, NO. 1, MARCH/APRIL 2016

In this issue . . .

10 In Memoriam - Ralph Beard 14 The Effect of Composition of a Calcium Sulfonate Complex Grease on the Key Parameters for Electric Motor Bearing Grease 26 Grease Lubrication for Longer Service Life in Angular Contact Ball Bearings 34 Assessment of Bearing Grease Anti-Corrosion Performance Using EMCOR Washout Test Rig

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ACTING PRESIDENT:

TREASURER:

David Como Dow Corning Corp.

P.O. Box 0994 Midland, MI 48686

Joe Kaperick Afton Chemical Corporation 500 Spring St. Richmond, VA 23218-2158

SECRETARY:

EXECUTIVE DIRECTOR:

Kim Smallwood Citgo Petroleum Corp.

1293 Eldridge Pkwy.

Houston, TX 77077

Kimberly Hartley NLGI Inter­national Headquarters 249 SW Noel, Suite 249 Lee’s Summit, MO 64063

PAST-PRES./ADVISORY: Chuck Coe Grease Technology Solutions LLC 7010 Bruin Ct. Manassas, VA 20111

DIRECTORS Barbara Bellanti Battenfeld Grease & Oil Corp. of NY P.O. Box 728 • 1174 Erie Ave. N. Tonawanda, NY 14120-0728 Richard Burkhalter Covenant Engineering Services 140 Corporate Place Branson, MO 65616 Faith Corbo King Industries, Inc. Science Road Norwalk, CT 06852 Gary Dudley Exxon Mobil Corporation 3225 Gallows Road Room 7C1906 Fairfax, VA 22037 Gian L. Fagan Chevron Lubricants 100 Chevron Way Room 71-7338 Richmond, CA 94802-0627 Jim Hunt Tiarco Chemical 1300 Tiarco Drive Dalton, GA 30720 Tyler Jark Lubricating Specialties Co. 8015 Paramount Blvd.

Pico Rivera, CA 90660 Dr. Anoop Kumar Royal Manufacturing Co., LP 516 S, 25th West Ave. Tulsa, Oklahoma 74127 Wayne Mackwood Chemtura 199 Benson Rd. Middlebury, CT 06749

Dennis Parks Texas Refinery Corp.

One Refinery Place Ft. Worth, TX 76101 Tom Schroeder Axel Americas, LLC P.O. Box 12337 Kansas City, MO 64116 Raj Shah Koehler Instrument Co. 85 Corporate Dr. Holtsville, NY 11716-1796 Dr. Huafeng “Bill” Shen Bel-Ray Co. P.O. Box 526 Farmingdale, NJ 07727 Terry Smith Lubrication Engineers, Inc. P.O. Box 16447 Wichita, KS 67216 Thomas W. Steib The Elco Corporation 1000 Belt Line Street Cleveland, OH 44109 Lisa Tocci Lubes ’n’ Greases 6105 Arlington Blvd., Suite G Falls Church, VA 22044 Mike Washington The Lubrizol ­Corpo­ration 29400 ­Lakeland Blvd.

Mail Drop 051E Wickliffe, OH 44092 Ruiming “Ray” Zhang R.T. Vanderbilt Company, Inc. 30 Winfield St. Norwalk, CT 06855

Dwaine (Greg) Morris Shell Lubricants 526 S. Johnson Drive Odessa, MO 64076

TECHNICAL COMMITTEE CHAIR, SESSION PLANNING:

Chad Chichester Dow Corning Corporation 2200 W. Salzburg Rd., C40C00 Midland, MI 48686

Wayne Mackwood Chemtura 199 Benson Rd. Middlebury, CT 06749

David Turner 22110 Stone Cross Court Katy, TX 77450

SERVICE INDUSTRY ASSISTANCE COMMITTEE CHAIR: J im Hunt Tiarco Chemical 1300 Tiarco Drive Dalton, GA 30720

EDITORIAL REVIEW COMMITTEE Joe Kaperick Afton Chemical Corporation 500 Spring St. Richmond, VA 23218-2158

SPOKESMAN

Serving the Grease Industry Since 1933 – VOL. 80, NO. 1, MARCH/APRIL 2016

6 President’s Podium 8 New 2016 NLGI Members 10 In Memoriam - Ralph Beard 14 The Effect of Composition of a Calcium Sulfonate

Complex Grease on the Key Parameters for Electric Motor Bearing Grease Solongo Wilson, Wayne Mackwood

21 Blast from the Past Cartoons 22 NLGI Member Spotlight 24 Ask the Expert 26 Grease Lubrication for Longer Service Life in Angular Contact Ball Bearings Ichimura Ryosuke

34 A ssessment of Bearing Grease Anti-Corrosion Performance Using EMCOR Washout Test Rig

Rahul Meshram, A H Zaidi, Kailash Yadav, Ajay Kumar Harinarain, Dr Naveen Pokhriyal, Dr S K Mazumdar and Dr E Sayanna

CO-CHAIRS:

CHAIR:

NLGI

OFFICERS

46 NLGI Industry News 49 Advertiser’s Index

ON THE COVER Book your hotel room now for the NLGI 83rd Annual Meeting!

Published bi-monthly by NLGI. (ISSN 0027-6782) KIMBERLY HARTLEY, Editor NLGI International Headquarters 249 SW Noel, Suite 249, Lee’s Summit, MO 64063 USA Phone (816) 524-2500, FAX: (816) 524-2504 Web site: http://www.nlgi.org — E-mail: nlgi@nlgi.org One-year subscriptions: U.S.A. $65.00; Canada $80.00; International $109.00; Airmail $147.00. Claims for missing issues must be made within six months for foreign subscribers and three months for domestic. Periodicals postage paid at Kansas City, MO. The NLGI Spokesman is indexed by INIST for the PASCAL database, plus by Engineering Index and Chemical Abstracts Service. Microfilm copies are available through University Microfilms, Ann Arbor, MI. The NLGI assumes no responsibility for the statements and opinions advanced by contributors to its publications. Views expressed in the editorials are those of the editors and do not n­ ecessarily represent the official position of NLGI. Copyright 2015, NLGI. Postmaster: Send address corrections to the above address.

15 N IO IS S V R E E O X R F O S D B N E R E V A M RO GE E I S PP ER W A ND O E N L F

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Passion for Solutions® is a registered trademark in the United States.

HIGH-PERFORMANCE GREASE ADDITIVES FOCUSING ON SOLUTIONS The LANXESS Corporation Rhein Chemie Additives business unit supplies a large number of additives that help improve the performance of greases. Most of these additives also meet stringent eco-toxicological requirements. Backed by extensive testing and years of experience, additives and formulations are expected to be available for every thickener system.

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PRESIDENT’S PODIUM

IMPORTANT NOTE:

The CLGS exam will be given at the 2016 STLE Annual Meeting on Monday, May 16th at 10AM. Please contact nlgi@nlgi.org to enroll in this course.

Terry Smith, Chair In the world of maintenance and lubrication, several lubricant-related technical organizations now certify lubrication expertise. These include the International Council for Machinery Lubrication (ICML), the Society of Tribologists & Lubrication Engineers (STLE), and NLGI International. Each has an established program that documents the major criteria for demonstrating knowledge and skill in lubricants and lubrication practices. But only NLGI’s Certified Lubrication Grease Specialist program identifies those individuals who have true expertise in lubricating grease. The letters CLGS after one’s name signify both fundamental and extended knowledge of grease formulations, grease processing, grease testing and grease applications.

This is important because grease doesn’t behave like other lubricants. It typically is produced in a sophisticated reaction process (not simply blended like other lubricants), and it requires unique understanding to correctly formulate, test, select and apply. While the other programs focus primarily on fluid lubrication but include some lubricating grease fundamentals, the NLGI’s Certified Lubricating Grease Specialist program deals almost exclusively with lubricating grease.

As a member of the NLGI Board of Directors, I know this first-hand. I hold credentials from all three

of the groups, and having the letters “CLGS” on one’s business card sends a message the others don’t: It says the individual possesses a defined level of expertise that is specific to the field of grease, and that NLGI recognizes this achievement.

Certification entitles one to use the copyrighted CLGS designation, and to be listed on the NLGI website as a grease expert. It can be a professional advantage in obtaining employment or going after business opportunities that require grease expertise, and it brings immediate credibility when working with customers. Employers use CLGS certification to screen potential employees, and OEMs and end users can use it to ensure that their suppliers are qualified to make grease recommendations.”

Obtaining CLGS begins with a closely monitored two-hour written examination. An 80 percent or better score is required for successful certification, which extends for a three-year period. To maintain certification, the candidate must renew their certification every three years and submit documentation to NLGI of continuing professional development, such as: • Attend an NLGI annual meeting • Present a paper at an NLGI annual meeting

-6VOLUME 80, NUMBER 1

• Attend an ELGI or NLGI India annual meeting • Publish a grease related paper in an industry publication • Present a grease related paper or training seminar at an industry meeting Or • Retake and pass the CLGS certification exam The CLGS exam will be given during NLGI’s Annual Meeting on June 14h, 2016, at 2:00PM in Hot Springs, VA. NLGI also offers an array of reference guides and education to help individuals achieve this important professional goal. For more information, visit NLGI’s website at https://www.nlgi.org/certifications/professional/certitficationinformation/

Terry Smith, Chair David Turner & Chad Chichester

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(Note: If your company is an NLGI member, you may login to our website’s ‘Members Area’ and obtain direct email addresses for all NLGI members.)

Axxess Chemicals – Supplier

Thames River Chemical – Supplier

Jay Lynn 522 Highway 9 North, Unit 110 Manalapan, NJ 07726 USA 732-851-1010 www.axxesschemicals.com

Axxess Chemicals, founded in 2009, is a valueadded global distributor of Molybdenum Disulfide, Polybutene, Base Oils, Transformer Oils and many other specialty chemicals. Although the grease and lubricant market remains the largest markets we service, Axxess Chemicals also services the needs of the Industrial, Pharmaceutical, Steel, Automotive, PTFE, Cosmetics and Adhesives industries.

Andy McGivern 5230 Harvester Road Burlington, ON L7L 4X4 Canada 905-220-2321 www.trc-corp.com

Thames River Chemical Corp. distributes chemical products in specialized markets across North America. As a member of the Canadian Association of Chemical Distributors we value the protection of health, safety and environment and ethical business practices.

The Unami Group, LLC - Technical

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Bill Tuszynski 27 S Vassar Drive Quakertown, PA 18951 USA 267-374-1631 www.unamigroup.com

Derek Benedyk 500 West Bradley Road, A#219 Fox Point, WI 53217 USA 312-206-4819 www.dtbtwo.com dtb2 LLC is a research and development company, dedicated to providing solutions for; unique lubricant formulations and applications, as well as, technical field service support and analysis of lubrication applications and processes.

The Unami Group, LLC is a consulting organization providing strategic, commercial and technical support to help clients identify and develop profitable business opportunities in the chemical, lubricant, materials and adjacent segments.

-8VOLUME 80, NUMBER 1

REGISTRATION NOW OPEN

NLGI 83rd Annual Meeting

The Omni Homestead • Hot Springs, VA, USA

June 11th -14th 2016 Watch Video

In Memoriam Ralph Beard

From NLGI… Our dear friend and colleague, Ralph Beard, passed away in Montgomery, AL on Thursday, March 3rd, 2016. All who knew him will mourn his loss.

Ralph was an active member of NLGI, STLE, SAE and ASTM. He had been very active in establishing the lubricant industry’s only North American undergraduate minor in the field, the Tribology & Lubrication Sciences Program at Auburn University. He also served on its Industry Board of Advisors. His support and efforts in these endeavors will be sorely missed.

Receiving his B.S. from Auburn University in 1971, Ralph began his over 45 year career in the lubricants industry with Union 76, followed by Keil Chemical and in 1981 he was named Technical Director of The Farm Oil Company. Returning to his native Alabama in 1990, he formed his own company, Triad Lubrication Components. He sold Triad to Palmer Holland in 2010, but continued to serve as V.P. of Lubrication Components. In the last few years he had served as the Global Lubricant Technical & Business Development Manager for Dorf Ketal and then served as Director of Corporate Development for Functional Products.

Goodbye, Ralph, we will always remember your kindness, wit, wisdom and tenacity.

- 10 VOLUME 80, NUMBER 1

I met Ralph years ago at an international conference where I'd been invited as a speaker but as a first time attendee was an outsider and frankly, feeling lost. At lunch, by happenstance I took the seat next to Ralph and by the time coffee came, I had a lifelong friend and colleague.

Ralph was warm, inviting, bitingly funny, humble, generous and a true gentleman; I will miss him enormously. My very deepest condolences to the Beard family on their immeasurable loss.

~ Sarah Krol, NSF International

In September, 2014, Ralph stayed at our house in Branson overnight on his way to Kansas. Auburn was to play Kansas State the next day in football and Ralph was an Auburn fan extraordinaire. While visiting, he noticed a 1/64th diecast model of a Union 76 (Unocal) tank truck I had in my collection. Come to find out, he had worked at the Unocal plant where years before I had done a consulting project. He had worked for Unocal for many years and the small truck brought back a lot of memories for him, many of which he expressed with great admiration.

Long story short, we presented him with the scale model Unocal tank truck as a gift at the 2015 NLGI conference. He said it would have a place of honor on his bookshelf at home. We were pleased to be able to bring a little joy from the past into his life. The truck couldn’t have had a better home. We’ll miss Ralph.

~ Dick Burkhalter

- 11 NLGI SPOKESMAN, MARCH/APRIL 2016

I first got to know Ralph at our Annual Meeting in 2009, Loews Ventana Canyon. It was a rough economic year, attendance was down. I stepped outside in the dark after the Tuesday dinner and I thought I heard Ron White! Turns out it was Ralph in his fur-lined Crocs, in June, in Arizona, and we were fast friends from then on. Of course, I don’t think you could meet Ralph and not be his friend. I will miss him very much, his humor, his passion for this industry and his zest for life. He went much too soon. ~ Kim Hartley, Executive Director, NLGI

I have known Ralph for over a decade and I still remember the first time we met. His southern hospitality and charm, as well as his unique sense of humor immediately drew me to him and ever since then, we became friends. Just thinking of him as I write this, brings a smile to my face.

The first time we met was at NLGI one late evening and we hit it right off. He spent over 2 hrs that evening with me, explaining all that he knew about an important subject : Bourbon ; which ones he liked and why, how to differentiate one bourbon from another, and I am certain I learned something more useful that evening from him, than I had, all that day listening to NLGI papers.

Ever since, and it has been over 10 years, whenever I do drink a bourbon, a smile crosses my face and I think of Ralph. He educated me on an “important subject”, that I knew not much about, like only he could, and I will always value that lesson from him all my life. As someone once said, some folks come into our lives and quickly go. Some stay for a while, and leave footprints on our hearts, and we are never the same. Ralph was one of those , who has left many a footprint in the lives of numerous NLGI members, both young and old. We will all miss you, my friend ~ Raj Shah

In Memory of Ralph From the Beard Family Ralph Beard, 67 years old and a servant of God, passed away suddenly on Wednesday, March 2nd, 2016.

He is survived by his devoted wife of 40 years, Janet Beard (Berglund), his two sons, Brian P. Beard and his partner Wesley Hansen; and Robert G. Beard and his wife Ashley Beard. He was also blessed with three beautiful granddaughters, Lola James Beard (Lee), 7 years old, Melody Bree Norwood, 7 years old, and Olivia Grace Beard, 10 months old. He was pre-deceased by his parents Ralph G. Beard Sr. and Roberta Threadgill Beard. Also mourning his loss are his extended family, friends, business associates and the Auburn University family.

Ralph was born in Birmingham, Alabama on September 4th, 1948. An only child, he considered his friends from the Woodlawn High School class of 1966 as his brothers and sisters for which he maintained strong bonds with until his death. Ralph went onto Auburn University and graduated in 1971 with a degree in Marine Biology. During these years, his passion for Auburn University grew, it became his life's work to support his alma mater, on and off the field. After college he married the love of his life Janet Berglund of Minnetonka, MN. There he raised two sons, coached little league sports and mentored many kids.

Returning to his Southern roots in 1990, he became a season ticket holder for Auburn football games. In that time, he started his own business and became a stalwart in the oil and lubrication industry. A learned man, he was often reading or looking for something else to discover. These traits he passed along to his sons. He never met an enemy and was loved by all.

Funeral Services were held at Holy Spirit Catholic Church at 8570 Vaughn Rd, Montgomery, AL 36117 at 1:00PM on Saturday, March 12th, 2016.

The family requests that in lieu of flowers, please make a donation to the Auburn University Foundation in memory of Ralph Beard. Send contributions stating in memory of Ralph Beard to the attention of David Mattox, Auburn University Samuel Ginn College of Engineering, 1320 Shelby Center, Auburn, AL 36849.

- 13 NLGI SPOKESMAN, MARCH/APRIL 2016

The Effect of Composition of a Calcium Sulfonate Complex Grease

on the Key Parameters for Electric Motor Bearing Grease Solongo Wilson Wayne Mackwood Introduction Calcium Sulfonate Complex (CSC) grease continues to grow in popularity as a premium grease for both end users and manufacturers. The 2014 NLGI Annual Survey has indicated that it accounts for almost 2% of the world grease production [1]. It is ideally suited to applications where heat, water, and high loads are present [4]. Several papers have shown that it can be used in a wide range of applications, from wheel bearings, food processing, nuclear power generation, steel mills, to marine equipment, and even wind turbines [2-13].

With Calcium Sulfonate Complex grease becoming more popular in heavy industries, and finding increasing use throughout a plant, its consideration for use in EMB lubrication is a natural next step.

This paper will present a first look at several aspects of formulating a high performance CSC grease for electric motor bearings. In particular it will examine the effect of base oil type, base oil viscosity, and thickener content on the performance properties of the grease.

Simply put, an electric motor can be defined as a Background machine that converts electrical energy into mechanical An evaluation of several electric motor bearing energy. Electric motors can make up more than half of manufacturers’ grease recommendations show that any plant’s rotating equipment. In mining, electricallythe most commonly suggested grease thickeners are driven draglines and shovels use electric motors for polyurea, lithium, and lithium complex [15]. There is powering all of the rotating equipment on board. These a distinct absence of calcium sulfonate complex grease motors can be lubricated by oil or grease, depending in these recommendations. This study sought to assess on the orientation or application. In the case of greasethe suitability of CSC grease in EMB applications, lubricated motors, the predominant grease of choice is despite concerns about relatively high thickener contents a polyurea-thickened grease, particularly for factorywhen compared to other greases. In fact, the focus of fill bearings [14]. Lithium Complex grease and even the study was the manufacture of a new low-thickener simple Lithium grease may be recommended and used. content product aimed at fulfilling the requirements Regardless of the type of thickener chosen, however, the of an EMB grease. Fig 1 below shows the evolution of primary functions of an EMB grease would be to reduce the calcium sulfonate grease technology from a simple friction, prevent wear, protect bearings against corrosion, thickener to processes with declining thickener contents. and act as a seal to prevent entry of contaminants.

Manufacturers of CSC grease have the option to vary Therefore, key properties to consider when formulating thickener contents from below 20% to over 30% [16would include high temperature life, operation at high 18]. The process described in Patent 5,308,514 (Method speeds, wear protection, and corrosion resistance.

C) results in thickener contents more in line with other Extreme pressure performance is not typically considered thickener types [18]. critical. A high percentage of electric motors operate at 3600 rpm, with a few operating at higher speeds of 5000 up to 20000 rpm.

- 14 VOLUME 80, NUMBER 1

Experimental Ten (10) lab-made samples were generated in order to investigate the effect of method of manufacture, base oil group (I-V), base oil viscosity and effect of polymer. The majority of the samples was made via a new method aimed at reducing overall thickener content. Selected samples were duplicated using the standard method of manufacture in order to make a direct comparison with their lower-thickener counterparts. The samples were generally formulated to a final base oil viscosity of 40cSt – a lower viscosity than typical commercially-available EMB greases (approx. 100cSt) – in order to offset the slightly higher thickener content. Furthermore, a viscosity of 40cSt was more easily achieved for all groups of base oil than formulating to 100cSt. All samples were trimmed to an NLGI Grade 2, additized with a standard aminic anti-oxidant and were all manufactured using a 400 TBN semisynthetic sulfonate.

Testing included dropping point (ASTM D2266), roll stability (D1831), PDSC (D5483) as well as in-house hot plate and oven panel testing. Finally, the rheological behaviour of all samples compared to two commercially available EMB greases was evaluated.

RESULTS AND DISCUSSION Table 1 – Summary of results All CSC samples gave excellent dropping values of 315°C+, good wear scar values <0.6mm and roll stability change under 10%, with the majority lying under 5%. With the exception of one, all CSC samples gave an OIT greater than 100min in PDSC testing.

When all of the above values are compared to those of two commercially available products, there are clear differences observed in dropping points, roll stability, and PDSC. Particularly noteworthy is the poor mechanical stability of the polyurea sample as well as its relatively low OIT of 26.7min when compared to the CSC samples.

- 15 NLGI SPOKESMAN, MARCH/APRIL 2016

The mineral oil lithium complex sample, which was the only grade 3 sample in the series, also gave a relatively low OIT of 29.8min. These results indicate that the anti-oxidant used in these formulations is not suited to provide significant protection against oxidation at temperatures as high as 210°C. The CSC samples were all formulated with an aminic AO which is seen to provide sufficient anti-oxidancy.

Hot-Plate and Oven panel testing These two tests served to characterize the high-temperature performance of the grease samples. In the in-house hotplate test, a pea-sized amount of each sample is subjected to a 440°C hot plate and observed for overall thermal stability. A poor-performing sample liquefies after a few seconds on the hot plate, whereas a thermally stable sample remains in solid form after several minutes on the hot plate. The results show a clear correlation to the dropping values as shown in Table 2 below.

Table 2 – Correlation of hot-plate test performance to dropping point results The oven panel test is a modified version of GM9075-P and involves coating a steel panel with a 30mil (0.8mm) film of grease and subjecting it to elevated temperatures (in this case 170°C) until the sample fails. Failure refers to excessive stiffening of the grease due to formation of oxidation products/resin. The panels were evaluated daily for change in colour, texture and presence of oil bleed.

The results showed a range in the number of days to failure, with the lowest number of days for the Group II samples. These samples had the overall lowest base oil viscosity of the series (ca. 28cSt) resulting in susceptibility to volatility. On the other hand, the best result was obtained from the mineral-LiX sample which was also the only Grade 3 sample present. Clearly, the amount of thickener – or conversely, the amount of oil – plays an important role in this test, since volatility is an important consideration. Further work on this study will include volatility testing (ASTM D972) Also apparent from the results was the significant colour change observed in the non-CSC based samples compared to the CSC samples.

The former turned very dark brown/nearly black, whereas the latter darkened by a few shades compared to the original as seen by the fresh sample placed in the middle of the panels.

- 16 VOLUME 80, NUMBER 1

Rheometry In order to characterize the visco-elastic properties of the samples, controlled-stress rheometry was performed at both low- and high temperatures using an Anton Paar Physica MCR 301 rheometer. In controlled-stress rheometry, a torque is imposed on one of the parallel plates (usually the upper) which sandwich a grease sample of known thickness. The resultant shear rate/ strain is measured allowing an analysis of the flow properties of the sample [22]. The instrument used in this study included software capable of generating such useful values as storage modulus (G’), loss modulus (G”), flow point, yield point etc. While it is true that in a parallel-plate set-up the shear rate varies from the centre of the plate outwards, the other commonly used geometry (cone-plate) also has its limitations.

High rotational speeds can result in high centrifugal forces, resulting in grease being flung out. Since high temperature testing was an important consideration in this study, a parallel-plate geometry using 25mm sandblasted plates was chosen for all testing.

Rheometry Results In order to compare the performance of the samples at various temperatures, the “flow point” value was recorded from all stress sweep runs [19]. The change (Δ) in this shear stress value (τ, measured in Pa) was represented as a factor of the sample’s value at 25°C. Larger delta values indicate a greater deviance (whether stiffer or softer) in the mechanical stability of the sample at lower or higher temperatures. Conversely, a relatively small change across a wide temperature range suggests that the sample is expected to perform well in the bearing at both decreased and elevated temperatures. For example, Fig 4 shows a factor of 19.6 when comparing the shear stress values of the 40cSt Group I sample at 25°C vs. at -25°C. Specifically, a shear stress of 6131Pa had to be applied to the -25°C sample in order to overcome the stiffening; this value is 19.6 times that of the 25°C shear stress value of 312Pa.

On the other hand, at an increased test temperature of 100°C, sample 1A was significantly softer, therefore a shear stress of 133Pa was sufficient to elicit the flow point, as shown in Fig 5, corresponding to a delta value of 2.3.

- 18 VOLUME 80, NUMBER 1

Stress sweep measurements were also carried out at -40°C and 195°C, the maximum temperature allowed by this particular instrument. A summary of all the delta values generated is shown in Table 3.

Table 3 – Summary of shear stress Δ values High-temperature testing revealed that there is little differentiation among the samples. At 100°C, most samples gave a Δ shear stress value between 1 and 4, with the exception of the synthetic ester sample (5) which gave a value of 12.3. Likewise, at 195°C there is little spread among the values, with the 2 non-CSC thickener samples giving the highest values.

Greater differentiation was seen in low-temperature rheological testing. The Group I samples showed the poorest performance at -25°C, particularly sample 1B which contains 1% of a typical VI-improver type polymer. The lowest values were achieved using PAO. At an even lower temperature of -40°C, valid readings were only obtained for the Group III and IV samples.

All others suffered from fracturing1 during the test measurement, leading to invalid readings.

The samples which showed the best performance across the entire temperature range were 4A and 4B, based on the standard and lower-thickener manufacturing

methods, respectively. By decreasing the thickener content in sample 4A from 25% to a value of 20.6% in 4B, improvements were seen across the entire temperature range.

Conclusions Using a method of manufacture which gives relatively low thickener content, a sample of calcium sulfonate complex grease based on PAO showed the best performance of all the samples generated. The sample gave good wear, excellent thermal and oxidative stability as well as good mechanical stability over a wide temperature range (-40°C up to 195°C). Such a sample would be suitable in a variety of electric motor bearing applications, particularly those that exist in harsher climates, e.g. mines in Canada. In order to further evaluate the performance of a proposed EMB calcium sulfonate complex grease, bearing life tests including ASTM D3336 and FE9 need to be performed.

Compatibility of CSC with polyurea would also need to be carefully evaluated.

1 – At low temperatures, “fracturing” refers to the formation of two separate layers in the brittle grease sample in response to the high initial applied shear stress (i.e. high starting torque). There is no flow or interaction between the two layers, resulting in free spinning of the upper spindle.

References 1. 2013 NLGI Annual Survey, NLGI 2014.

2. Muir, R. “High Performance Calcium Sulfonate Complex Lubricating Grease” NLGI Preprint, 1987 Annual Meeting.

3. Kimura, Y., Takemura, J., Araki, J., Kojima, H., “Study of Synthetic Oil Based Calcium Sulfonate Complex Grease”, Preprint, 2005 NLGI Annual Meeting.

4. Mackwood, W., Muir, R. “Calcium Sulfonate Grease… One Decade Later” NLGI Spokesman, Volume 63, No. 5, 1999.

5. Mackwood, W., Muir, R., Brown, K., Austin, E. “Reduction in Power Plant Maintenance using Calcium Sulfonate Complex Grease” Preprint, 2003 ELGI Annual General Meeting.

6. Samman, N., “High Temperature Greases” Preprint, 2006 NLGI Annual Meeting.

7. Schlobohm Sr., J., Faci, H., Cisler, B. “Steel Mill Greases: Evaluation and Analysis”, NLGI Spokesman, Volume 69, No. 8, 2005.

8. Mackwood, W., Muir, R., Dunn, W. “Calcium Sulfonate Complex Grease. The Next Generation Food Grade Grease.” NLGI Spokesman, Volume 17, 2003.

9. Mackwood, W. “The Next Generation Food Machinery Grease 10 Years On”, NLGI India Conference, Ooty, India, February 3-5, 2011.

10. Schlobohm J. Sr., Faci, H. Cisler, B. “Steel Mill Greases: Evaluation and Analysis” NLGI Spokesman, Volume 69, Number 8, pp. 8-13, November 2005.

11. Kumar, V., Nagar, S.C., George, TP., Sayanna, E., Mooken, R.T., Naithani, K.P., Malhotra, R.K. “Specialty High Performance Grease for Multipurpose Applications”, Presented at the NLGI India 2011 Conference, Ooty India, February 3-5, 2011.

12. Singh, T., Banerjee, S.K., Ravi, K. “Grease Compostion for Steel Plant Application”, Presented at the NLGI India 2011 Conference, Ooty India, February 3-5, 2011.

13. Mackwood, W. “Calcium Sulfonate Complex Grease. 25 Years Young.” Proceedings of the 2012 LTEF, Dalian China, 2012.

14. Underwood, “Grease-Lubricated Electric Motors – A New Perspective”, Machinery Lubrication (1/2008) 15. Christensen, P. “Lubrication of Rolling Bearings in Electric Machines”, EASA Tech Note No.19 16. Muir R.J., Blokhuis, W. “High Performance Calcium Borate Modified Overbased Calcium Sulfonate Greases” U.S. Patent 4,560,489 (1985).

17. Olson, W.D., Muir, R.J., Eliades, T. “Sulfonate Grease Improvement” U.S. Patent 5,338,467 (1994) 18. Olson, W.D., Muir, R.J., Eliades, T., Steib, T. “Sulfonate Greases” U.S. Patent 5,308,514 (1994) 19. Lugt, “Grease Lubrication in Rolling Bearings” SKF; Wiley p.111 20. Delgado et al, “Thermorheological Behaviour of a Lithium Lubricating Grease” Tribology Letters, Vol.23, No.1, July 2006 21. Salomonsson et al, “Oil/Thickener Interactions and Rheology of Lubricating Greases”, Tribology Transactions, 50:302-309, 2007 22. Mezger, T. “The Rheology Handbook”, Vincentz-Verlag, Hannover, 2011

- 20 VOLUME 80, NUMBER 1

NLGI Spokesman magazine, August, 1949

A BLAST FROM THE PAST

NLGI Spokesman magazine, August, 1948

Book Your Hotel Room Early!

NLGI Spokesman magazine, August, 1948

NLGI MEMBER

SPOTLIGHT

We hope you’ll enjoy learning more about our long-time member, Dow Corning. Their contribution to our Board of Directors has been outstanding over the years and we’re proud to feature their company in our new NLGI Member Spotlight.

Dow Corning (dowcorning.com) provides performance-enhancing solutions to serve the diverse needs of more than 25,000 customers worldwide. A global leader in silicones, silicon-based technology and innovation, Dow Corning offers more than 7,000 products and services. Dow Corning is a joint venture between The Dow Chemical Company and Corning, Incorporated. More than half of Dow Corning’s annual sales are outside the United States.

Dow Corning’s global operations adhere to the American Chemistry Council’s Responsible Care® initiative, a stringent set of standards designed to advance the safe and secure management of chemical products and processes.

Company: Dow Corning Corporation Member Category: Manufacturer Contact Name: Chad Chichester Country: USA Address: C orporate Center, 2200 W. Salzburg Rd., PO Box 994. Auburn MI 48611 Telephone: (989) 496-8025 Email: Chad.chichester@dowcorning.com Website: www.dowcorning.com

Molykote® is the brand name for over 600 specialty lubricant products from Dow Corning. For more than 65 years, engineers worldwide have relied on Molykote® brand to help solve or prevent lubrication problems and to help save energy by reducing friction and wear.

The Molykote® lubricant product line is unique in that it contains six different primary product groups.

The six primary Molykote® product groups are: • O ils – Synthetic and mineral oils with performance additives and/ or lubricating solids to protect machine surfaces • G reases – Synthetic and mineral oil-based products thickened with various thickening systems • S ilicone Compounds – Siliconebased, noncuring heavyconsistency materials used as sealants, release agents and moisture barriers.

• A nti-Seize Pastes – Lubricating solids dispersed in various - 22 VOLUME 80, NUMBER 1

fluids help prevent galling and damage under high loads. Even if the carrier fluid is removed, the solids maintain a reliable and strong lubricating film on surfaces • A nti-Friction Coatings (AFCs) – Paint-like coatings that dry to a slippery film, filling in surface asperities and providing longterm boundary wear protection in dusty, dirty environments.

• D ispersions – Oils, greases, compounds, or pastes dispersed in solvent for easy application on components, otherwise too difficult to reach with other lubricants

Dow Corning, Scientist Emeritus, Dave Como was recently appointed to the Office of NLGI President.

Dave has represented Dow Corning at NLGI for over 30 years as an NLGI member, course instructor, course chairman, Board member, and member of the Executive Committee. Since 1985 Dave has held a variety of technical service, product development, and leadership positions in Dow Corning’s Lubricants Expertise Group.

“I am truly honored by this appointment and will strive to fill the sizeable shoes left by our outgoing president, Bruce Urban, as well as the legacy left by his predecessors since 1933. The integrity of NLGI is a time-honored tradition in industry that is global in its reach.”

Dow Corning Lubricants Application Engineer Chad Chichester was recently named NLGI Technical Committee co-chair.

In his appointed role, Chichester will apply more than 20 years of experience to help ensure that NLGI remains on the leading edge of new lubrication technology and is well-informed in matters related to manufacturing, research, industrial standards and government regulations.

“Our Dow Corning Molykote® team of experts – including Dave and Chad – is extremely well-integrated into industry networks, frequently delivering presentations and authoring technical articles and papers for organizations and publications. Members of the Molykote® team regularly demonstrate their expertise and innovative spirit for the benefit of customers and for the advancement of their chosen field,” said Industrial Assembly and Maintenance Global Segment Leader Geert De Backer. “Dave’s appointment to NLGI President and Chad’s invitation to serve as NLGI Technical Committee co-chair acknowledges the value of these contributions and gives them the opportunity to help the lubricants community benefit from Dow Corning’s 60-plus years of expertise and leadership.”

“Having previously been active as an instructor and course chair, this new role feels like a very logical next step in my NLGI involvement,” Chichester said. “I’m honored to have been selected to serve in this way, and I look forward to helping increase the knowledge and level of expertise among the NLGI community.”

NLGI is proud to announce the introduction of the ‘NLGI Member Spotlight’, a new feature of the 2016 all-digital Spokesman magazine.

All NLGI members may take advantage of this opportunity to highlight your company’s history, global reach, vision, employees or whatever you’d like our readership to know about your company. You may talk about products & services, however, no competitor trade names may be used, nor mention of product pricing.

There is no limit on words and we welcome many photos

of your headquarters, offices, plant & employee photos. We will accept articles for publication on a first received, first published basis. Contact Marilyn Brohm Marilyn@nlgi.org at NLGI if you would like to submit an article for possible publication in an upcoming issue.

There is absolutely no charge to have your article appear in the NLGI Member Spotlight

Q:

the Expert

Q: Can you provide an explanation regarding the What types of greases are used in the following mills: temperature capability of some standard high temperature steel mills, lumber mills, sugar mills & paper mills? greases and how to interpret and compare the values typically listed for each product? Drop point, Flash point, A: maximum operating temperature. There is some debate Steel mills – The steel industry originally used clay here about how to apply a product and what the different greases, as they were the only high-temperature products product descriptors indicate. of the time. The industry moved to aluminum complex when it was introduced. Some steel mills continue to use A: aluminum complex grease, while others have moved to The maximum operating temperature of lubricating greases is reported differently by different suppliers. First, lithium complex products for general lubrication. Some applications use polyurea greases with synthetic base fluid. we will discuss the terms that you have listed: Dropping Point is basically the temperature at which the thickener in a grease melts, as determined in various test methods. The melting of the thickener results in the grease becoming fluid enough to run out of the dropping point test cup. Greases should not be used at temperatures approaching the dropping point.

Flash Point is a property of the fluid component of a grease. The flash point is the temperature at which the vapors of the fluid momentarily ignite when an ignition source is applied. The flash point is typically well above the operating temperature of the grease.

The maximum operating temperature of a grease is typically determined by how the grease performs in bearing tests at elevated temperature. Such tests include ASTM D3336, ASTM D3527, FAG FE-9, etc.

Lumber mills – This application does not have the extreme conditions found in the steel or paper industries.

The lumber industry has typically used lithium, lithium/ calcium, or lithium complex greases.

Sugar mills – The sugar industry is characterized by heavy-loaded, slow-moving plain bearings. The greases used in the sugar industry have historically been calcium soap or clay thickened, with high (ISO 1000 or higher) base oil viscosity and lubricating solids, such as molybdenum disulfide.

Paper mills – The typical paper machine has both high water (wet end) and high temperature (dry end) applications. In general, lithium complex greases are used, while some specialized applications require products such as polyurea grease with a synthetic base fluid.

Q: It is recommended that you discuss the specific What type of grease is the thickest but still is a lubricant application and temperature range with your grease to take up or make up the gear mesh? supplier so that the supplier understands the requirements and can supply a product with the appropriate A: temperature range capabilities for the operating The use of a grease in place of gear oil in a worm gear conditions. will not make up for excessive slack in the gear set.

- 24 VOLUME 80, NUMBER 1

Although grease has consistency (stiffness), it will still flow under conditions of shear, and will not fill the gap in a poorly matched worm and wheel set. Worms and their mating wheels are typically machined together as a matching set. If the slack between the worm and wheel is such that vibration or shudder is present when the gearbox is operated, the gearbox should be replaced or the worm/wheel pair re-machined to make them match better.

Q:

We are trying to manufacture Lithium based grease with high transparency. Any advise on it?

A:

Transparent, or at least translucent, lithium soap greases tend to be made with light-colored base oils and additives that do not cause them to become opaque. The degree of translucency is related to the amount of thickener in the product. A product with less thickener Most worm gear units are lubricated with a gear oil that will be more translucent, since it is the thickener is specifically formulated for that application. Lubricants that causes the oil to become opaque. Less thickener for worm gears include high viscosity (ISO 460 or 680 (better yield) in the grease is controlled by the base oil viscosity grades) compounded mineral oils, synthetic characteristics (chemical make-up, solvency) as well as non-EP (non extreme pressure) lubricants based on the manufacturing procedure and conditions. A product polyalphaolefin (PAO) fluids in the ISO 220, 320, or 460 that contains a significant portion of naphthenic base viscosity grades, or synthetic non-EP lubricants based oil (relatively low aniline point) will have a better yield on polyalkylene glycol (PAG) fluids in the ISO 150, 220, (contain less thickener) than a product based only on 320, 460, or 680 viscosity grades. Although grease is paraffinic base oils. In particular, if the soap is formed in sometimes used to lubricate worm gears, it is uncommon, naphthenic base oil during saponification, the yield will as the EP additives used in many greases can be aggressive be significantly improved. A word of warning, though toward the bronze wheel. The EP additives in gear oils - if the thickener content is too low, the oil separation, designed for use in spur gears can also be problematic. mechanical stability, and water resistance properties of the Those types of lubricants should be avoided. Also, if the grease can be affected. Grease formulation is a balance, bronze alloy contains aluminum, PAG based worm gear and striving for transparency should not be allowed to lubricants should be avoided. compromise other performance properties.

Grease Lubrication

for Longer Service Life in Angular Contact Ball Bearings Ichimura Ryosuke, Kyodo Yushi Co. Ltd

1. Introduction

Due to the easiness in use, grease is used for lubrication for various fields and applications such as ball bearings, mechanical parts, industrial machines and electromechanical equipment, and aerospace industry.

80% of ball bearings use grease lubrication, for which efforts have been made for long years for developing lubricating grease applicable for rolling bearings. The recent user requirements for downsizing and use at higher revolution speed are severe for such rolling bearings.

A remarkable type of damage that can occur on grease lubricated rolling bearings is seizure due to the sudden increase in torque especially at high temperature and/ or high speed. The time required for seizure to occur is called the grease lubrication life that has been studied by many researchers. Lugt1) mentioned that the oil separated from the grease and staying on the surface of the bearing seal or shield, or near the race plays the most important role for lubrication. Cann et al. 2) mentioned that, as a result of studying the behavior of the grease in a ball bearing operating at high speed and low load, such the clear oil separation couldn’t be recognized, and propped that grease lubrication occurs as a result of softening of the grease near the friction part due to cyclic shearing loading at the contact area. Wikström and Jacobson3) proposed a simple model to evaluate the lubrication life based on the balance between “feed” and “loss” of lubrication oil at the contact area that needs lubrication. However any of these research efforts has not interpreted the mechanism completely, no unified theory being yet to be given.

This study carried out lubrication grease life tests using aromatic diurea grease and aliphatic diurea grease to measure damages leading to the termination of the lubrication life and then observed the movement of the grease in the bearing with a view to demonstrating characteristics required for long life lubrication and developing a long life lubricating grease for angular contact ball bearings.

2. Experiment 2-1. Grease sample

Table 1 shows the composition and properties of the greases used for the test. These two greases comprise a base oil of paraffin mineral oil and a thickener of aromatic diurea compound for the sample A and aliphatic diurea compound for the sample B. Samples A’ and B’ are, as mentioned later, greases containing ZnDTC and MoS2 respectively. All of these grease samples do not contain additives except antioxidant and those specified by the table. All of them have the same consistency resulting from adjustment in the content of thickener.

2-2. Testing machine and conditions

The lubrication oil life test used FE9 test machines designed according to the relevant DIN standard requirements. Figure 1 shows a schematic of the machine. The bearing under test is mounted on one end of the main axis of the testing machine, and a support bearing is mounted on the other end of the axis. The bearings receive only axial loads the magnitude of which corresponds to the compression of the disc spring inserted between the bearings. The outer ring of the bearing is heated by a heater located in the housing in a controlled manner using a thermocouple attached to

- 26 VOLUME 80, NUMBER 1

the ring so that the temperature is maintained constant.

The bearing under test is an angular contact ball bearing 7206B without seal.

Test conditions: axial load = 1500N, rotation speed = 6000rpm, bearing outer ring temperature = 120°C and grease fill = 4g The machine was stopped when the measurement of the machine’s driving power increases quickly to the specified limit. This point was assumed to represent the frictional torque that corresponds to the termination of lubrication life. Note that the value of the driving power limit depends on the value of the normal operating torque that differs machine head by machine head.

3. Result and discussions 3.1 Lubrication life and mechanical damages observed during the life

Figure 2 shows Weibull plots for the lubrication life tests for grease samples A and B. The 50% life, L50 was 130h for the sample A and 580h for the sample B. These two grease samples have the same type of base oil and additives, and same level of consistency. However the difference in the type and amount of thickener contained contributed to a great difference in the lubrication life. To investigate the damages that occurred in the bearing during the test, the bearing under test was cleaned by washing after the test. Figure 3 shows typical observations of various areas. Figure 3(1) and (2) shows that discoloration occurred on the surface of both the inner and outer races though no other changes in appearance that might occur due to quick increase in frictional torque were observed. However on the rim of the window of the cage, seizing marks were observed locally as shown in Fig. 3(3). Therefore, we supposed that under the conditions applied for this test, seizing between the cage and steel balls directly causes the lubrication life to terminate.

3.2 Formation of grease lumps and their change

To investigate the movement of the grease in the bearing during its operation, the machine that had been operating under the above mentioned test conditions was stopped halfway in the test and the grease was observed.

Before the test, the spaces between the steel balls were

filled with grease.

After starting the machine, the grease was churned for about one hour, and then gathered at the three locations to form grease lumps as shown in Fig. 4: (a) at the end of the bearing, (b) inner surface of the outer ring and (c) cage interior. These lumps remained unchanged until the lubrication life terminated. Among them, the location (a) was the largest.

However, though the location (a) remained unchanged with respect to the shape, it was likely that it became “lean” with time so that the volume of the grease reduced. To determine how the grease in the location (a) contributes to the lubrication and how it affects the lubrication life, after operating the grease-filled bearing for two hours, the machine was stopped and the grease location (a) was removed, and then the machine was put in operation again. As a result, as shown in Fig. 5, the life measured 26 h for the sample A and 46 h for the sample B. Note that the life measured was significantly shorter than that measured first with the location (a) remaining not removed. This supports a hypothesis that the location (a) stays at a fixed position as a whole and works as a source of oil to lubricate between the cage and steel balls.

Next, the hypothesis was verified, as follows.

3.3 Verification test using tracers

The behavior of the grease and its individual components in the bearing was investigated by using tracers: Zn from ZnDTC was dissolved into the base oil as a tracer of oil; and Mo (solid) from MoS2 was mixed with the thickener as a tracer of the mixture of grease and thickener. These samples containing such traces are named Samples A’ and B’ respectively, as shown in Table 1. First, the bearing filled with the sample A or B was operated for two hours, and the grease was removed from the bearing. Then a cover pocket (a’) filled with the sample A’ or B’ was attached to the bearing as

- 27 NLGI SPOKESMAN, MARCH/APRIL 2016

shown in Fig. 6 and the bearing was put into operation again. Then a procedure of stopping the operation of the bearing and collecting grease of 20 mg from the cover pocket (a’) and location (b) was repeated as required.

The grease collected was analyzed by X-ray fluorescence spectrometry to measure the concentration of Zn and Mo. Figure 6 shows, as a function of operation time, the concentration of these elements presented relative to the unity of initial value.

The concentration of Zn in the cover pocket decreased with time while it increased in the location (b) formed on the inner surface of the outer ring. By contrast, the concentration of Mo in the cover pocket remained almost unchanged, and no Mo was detected in the location (b). This result clearly indicates that the grease in the cover pocket (a’) – grease lump (a) formed at the bearing end in the test of Section 3.2 – hardly moves though the oil separated from the grease moves into the location (b). As compared with the sample A, the sample B shows a larger rate of increase in Zn concentration as shown in Fig. 6 (right), which means that a larger amount of oil is fed into the space between the cage and steel balls whereby the lubrication life is elongated.

3.4 Process leading to the termination of lubrication life Our investigations for possible causes of the termination of the life found that seizing at the sliding contact area between the cage and steel balls due to insufficient lubrication is a direct cause of the termination of lubrication life. Discussions about the lubrication on major contact areas in a ball bearing – rolling contact areas between the race and balls and sliding contact areas between the cage and balls – are shown below.

Grease in a contact ball bearing is in a churning period where the grease is stirred or in a channeling period where most of the grease is moved to other locations in which it will settle. It is known that the churning period does not last long before entering into the channeling period.

In the churning period, grease does not yet settle down though a relatively large amount of grease is staying

near any of the contact areas so that a thick EHL film is formed on the rolling contact areas of the race, whereby the sliding contact areas are well fluid-lubricated as a whole. Under such favorably lubricated conditions, it is likely that the cage can easily correct the lead or lag in the revolution of the balls. However, in this condition, the frictional torque is normally larger since the grease is stirred in the bearing.

As shown in Fig. 7(1), in the churning period, the grease between the race and balls is displaced by the moving balls. The displaced grease and the grease that has adhered on the cage will be moved to certain locations that are determined mainly by the centrifugal force applied. This is the transition to the channeling period. For an angular contact ball bearing, the grease will settle down by forming lumps on the cage, inner surface of the outer ring, and on the cover of the bearing.

In the channeling period, the grease lumps formed hardly move: they, as a form of grease, do not move in the bearing. They work as supply sources of oil to the contact areas. Oil supplied from the grease is conveyed by the rolling motion of the balls to the contact areas that need lubrication. The condition of lubrication at a contact area is determined by the combination of the “feed” characteristics that govern the movement of oil in the grease and supply of oil to the contact areas and the “loss” characteristics that govern the exhaustion of oil due to oxidation and/or evaporation from the contact areas.

Seizing on the sliding frictional surface between the cage and balls, a direct cause of terminating the lubrication life, leads to a shortage of oil supply, which results in the failure of balance between feed and loss of oil at the contact areas that need lubrication. Also, the shortage of oil supply at the rolling contact areas between the inner/outer rings and balls causes the friction to become larger due to insufficient lubrication, which in turn leads to a larger load acting on the sliding contact areas between the cage and balls when it is necessary to correct lead or lag in the revolution of the balls. This can be an indirect cause of seizure at the contact area.

- 28 VOLUME 80, NUMBER 1

4. Conclusion

An angular contact ball bearing filled with urea grease underwent a lubrication life test. As a result, we found: (1) Under the same conditions as applied for this test, the termination of the grease lubrication life is caused by seizing on the sliding frictional surface between the cage and steel balls.

(2) he grease in the bearing, after the churning period that occurs initially after starting the operation of the bearing, will gather at (a) the bearing end, (b) inner surface of the outer ring and (c) cage interior. The grease lumps formed do not move.

(3) The grease lumps work as supply sources of oil to the contact areas. Oil supplied from the grease is fed to the contact areas between the cage and steel balls that need lubrication. In the event that the oil feed is in short supply, the lubrication life is terminated.

(4) We succeeded in tracing the movement of grease and oil in the bearing under this test condition using tracer elements.

(5) To elongate the lubrication life, it is effective to control and optimize the movement of oil supplied from the grease in the bearing.

References

1) P. M. Lugt: Grease Lubrication in Rolling Bearing, Wiley, 2012, 157.

2) P. M. Cann, J. P. Doner, M. N. Webster, V. Wilstrom: Grease Degradation in Rolling Element Bearrings, STLE preprint 01-AM-3, (2001)1-6.

3) V. Wikström, B. Jacobson: Loss of lubricant from oil-lubricated near-starved spherical roller bearings, Proc Instn Mech Engrs, Vol211, Part J,(1997)51-66.

- 29 NLGI SPOKESMAN, MARCH/APRIL 2016

- 30 VOLUME 80, NUMBER 1

- 31 NLGI SPOKESMAN, MARCH/APRIL 2016

28th ELGI AGM 16th – 19th April 2016 Hilton Molino Stucky Venice

Sustainability in the grease industry

• Green Lubrication • Goals to Conserve Natural Resources • Renewable Feedstock • Natural Science Chemistry • Environmental Management • Green Legislation • Minimal Impact Technology • Extended Performance Meet colleagues in the lubricants industry from 28 different countries in 2016 in Venice, an exciting historical city, where a series of islands formed by many canals played an important role in world history.

- 32 -

VOLUME 80, NUMBER 1 ELGI, Hemonylaan 26, 1074 BJ Amsterdam, Netherlands Telephone: +31 20 67 16 162 Email: carol@elgi.demon.nl Online: www.elgi.org

71st STLE Annual Meeting & Exhibition May 15-19, 2016 Bally’s Las Vegas Hotel Las Vegas, Nevada (USA) Technical and professional development you can’t get anywhere else!

When it comes to advancing your career and upgrading your technical knowledge, STLE’s Annual Meeting & Exhibition is a singular event in the lubricants industry.

1,600 of your peers in the lubricants community are expected to participate in STLE’s 71st Annual Meeting & Exhibition. Please join us in Las Vegas for a unique experience that blends the best of industry education, technical training, professional certification and new technologies.

PROGRAM HIGHLIGHTS • • • • • • • • • • •

500 Technical Presentations 12 Industry-Specific Education Courses 90-Exhibitor Trade Show Commercial Marketing Forum Networking New Products Professional Certification Peer Recognition Emerging Technologies Student Posters Business Planning

Visit www.stle.org for regular program updates and to register.

Follow us on

#STLE2016

- 33 NLGI SPOKESMAN, MARCH/APRIL 2016 Society of Tribologists and Lubrication Engineers, 840 Busse Highway, Park Ridge, IL 60068, info@stle.org, www.stle.org, 847-825-5536

Assessment of Bearing Grease Anti-Corrosion Performance Using EMCOR Washout Test Rig Rahul Meshram, A H Zaidi, Kailash Yadav, Ajay Kumar Harinarain, Dr Naveen Pokhriyal, Dr S K Mazumdar and Dr E Sayanna Indian Oil Corporation Ltd, R&D Centre, Sector 13, Faridabad (Haryana), India.

1.0 Abstract: Greases are designed to protect bearings from corrosion during operation. Bearing greases are supposed to withstand conditions of cooling water spray and washout.

The SKF EMCOR test is an age-old, standard test method used for the evaluation of dynamic anti-rust performance in bearings. However, this evaluates the corrosion performance of greases with bearings remaining dipped in stagnant water. This may not be a true representation of the severe conditions in plants where the cooling water constantly flows through the bearing housing and may lead to the grease being washed out and not being available for corrosion prevention.

To account for this aspect, the modified EMCOR test rig with a water washout attachment was used to evaluate greases simulating conditions in the laboratory closer to those present in a steel plant environment. The antirust performance of several greases was evaluated in the EMCOR test rig with and without water washout. A correlation was attempted based on these studies, and a better understanding of the factors affecting grease corrosion performance was developed during these studies.

2.0 INTRODUCTION: Greases offer significant benefits over oils in bearing lubrication. They provide inherent sealing properties

thus keeping contaminations away from the surfaces to be lubricated. They also act to resist the washing effect of water in bearings and machine components. Grease can be used in open bearing components and even in vertical orientations by virtue of its retentive properties. In bearings, the reservoir of grease (either moved to the side or kept on the side) takes care of replenishment when the thin film existing earlier degrades or dries due to oxidation, thus protecting components at all times. It is estimated that greases lubricate over 90% of all bearings (source?), thus it is the preferred choice for lubrication of bearings.

Bearing lubrication presents several challenges to the grease formulators. They have to do a balancing act of working with minimal quantity lubrication coupled with long bearing life (the same as that of the bearing itself).

Additionally, they have the above challenges of working to keep the contaminants out and being able to work with ingress of water. The performance demands on the grease include working at higher speeds, loads, and temperatures and for extended relubrication intervals.

This imposes severe demands on the grease used in such bearings. In this context, it becomes a complex task to predict the lubricating life or the relubrication interval to prevent lubrication or bearing failure with

- 34 VOLUME 80, NUMBER 1

uncontrollable factors like contamination with water.

Greases of different chemistry behave differently on contact with water so their performance also varies differently.

with the ingress of varying quantities of water. Water with free electrolytes due to presence of various salts dissolved in it may lead to problems of galvanic potential leading to corrosion.

In this context, to be able to formulate the right grease for the right application, taking into consideration these requirements, the right testing methodology has to be worked out. Several standard tests are available for this purpose to guide the formulators to develop the right product. Standard tests are available, but these suffer from limitations of not being able to correlate with the conditions encountered in service. In such a case, it is necessary to modify the test conditions on the standard equipment or develop new equipment altogether that simulates the conditions in a better way.

A white paper by Axel Christiernsson [6] reviews and gives insights into which greases are water resistant and do well under wet conditions when lubricating a bearing.

This paper also gives an overview of the popular test methods used in industry for evaluating water ingress in greases in

3.0 LITERATURE REVIEW: Corrosion prevention is an important part of lubricant development. Any oil or grease used in service conditions ideal for corrosion of metallic parts has to be able to prevent corrosion of the surfaces to prevent premature failure of the same.

As per McKibben [ 1 ] relating to the relation of Humidity Cabinet life of lubricants to their service life, corrosion is significantly dependent upon Humidity (H) and temperature (t). Corrosion proceeds at negligible rates at lower temperatures and humidity. So it is very necessary to look more closely at corrosion problems where the temperatures are high and ingress of moisture and free flowing water occurs.

C=((H/23.4)-1.28) x 2(t/18) It has been estimated in studies by bearing manufacturers like SKF and Timken [2,3] that even a small amount of water (less than 1%) in the grease shortens the life of rolling element bearings. Lugt[4,5] has described that some greases perform well with water present, while some do not. Water ingress can occur due to a number of reasons - some due to use of water as a coolant for bearings in steel plants, in some cases, due to condensation of moisture in the bearings, due to temperature changes, and, sometimes, due to machine malfunctions which cause water to reach inside the bearings. It is necessary to know how the grease structure that is primarly responsible for its performance changes

a bearing. A recent publication by Leckner [7] of the same organization has documented the available industry methods to assess the ability of various lubricating greases with different thickener systems to perform when contaminated with water. This paper also tries to validate the laboratory results with actual field data about the performance.

The failure modes due to the ingress of water in the bearing have been documented by Fitch [8]. These include the hydrogen-induced fractures due to hydrogen embrittlement and blistering. This occurs when water comes in contact with free metal in the microscopic fatigue cracks in balls and rollers. Corrosion and rusting renders surfaces unusable due to rapid formation of etched and pitted surfaces. High temperatures and water ingress consume the antioxidants rapidly reducing the protection required causing corrosion, sludge, varnish etc. Other additives like AW, EP, rust inhibitors, etc. get depleted in the lubricants in the presence of water. Film strength of lubricants like greases and oils in bearings gets impaired due to presence of water. Bearings work in EHD and boundary lubrication so the surface protection imparted by film strength gets impaired causing premature failure.

In their paper, Folger et al [9] list the top causes of bearing damage, and have indicated that as little as 1% of water in grease or oil can significantly shorten the bearing life. They indicate that moisture or water ingress in bearings leads to etching or corrosion in bearings.

Even bearing surfaces left idle for long periods are susceptible to corrosion in bearings, so greases should protect surfaces at all times during operation as well as storage.

- 35 NLGI SPOKESMAN, MARCH/APRIL 2016

Authier et al [10] has presented a study on use of calcium sulphonate grease as a water resistance grease which is able to successfully overcome problems due to water ingress in bearings even at high temperatures.

This grease works well with water due to its inherent properties which are able to offer great performance in the laboratory tests as well as during field trials.

The paper offers a comparison with other chemistries of greases and notes that under conditions of high temperatures and water ingress into bearings, calcium sulphonate greases offer the best solution.

4.0 REVIEW OF TEST METHODS IN PRACTICE: To be able to evaluate the water ingress effect on performance as well as corrosion resistance of greases, it is required to run tests on greases using the metallic components in contact with water. These tests give a directional indication of the ability of a grease to prevent corrosion, however, it would correlate with field performance only if a dynamic test using the actual component being lubricated were run on the grease. It would also be useful to maintain the test conditions as close as possible to the actual field conditions in terms of load, speed and temperatures, as well as the contact with the water or the process fluid as in actual service.

Various tests have been used and standardized by ASTM, IP, DIN and ISO over the years to assess the performance of greases in the presence of water. Some of these are listed below: (a) DIN 51807 water resistance test is used to assess the grease’s physical resistance in the presence of water.

In this test, a thin layer of grease is applied to a glass plate. It is then dipped in hot water, kept in a test tube and allowed to stand for three hours. A visual inspection after this static test assesses the change in the grease after the test, with “0” indicating no or little change and “3” meaning that the grease has significantly dissolved or dispersed in water. (b) In the ISO 11009 water washout test, the ability of the grease to withstand water under washout conditions is evaluated. This dynamic test uses a SKF 6204 C3 bearing filled with 4 grams of the grease rotated at 600 rpm for an hour during which a jet of distilled water at the rate of 5 ml/sec

is sprayed on the bearing shield. The temperature of the water is maintained at 37.8oC or 79.4 oC (100°F or 175°F) depending upon specification requirements for the grease. It is also possible to use various fluids, salt water, sea water or process fluids depending upon the requirements. After the test, the bearing is dried and amount of grease in the bearing is calculated. Values of washout below 10% are usually considered acceptable performance limits. (c) A STM D4049 water spray off is a test used to evaluate the retentive ability of the grease to stay in place on an open plate when subjected to a high pressure shower of water. In this test, a stainless steel plate is coated with a 0.8 mm thick film of grease. It is weighed and stationed at a specific angle ranging from 55o to 65o in the apparatus. The water is heated to 38 oC and sprayed at the plate at a pressure of 276 kPa(40 psi) over the sample for 5 minutes. The plate is then dried and weighed to estimate the remaining amount of the grease. A grease should ideally achieve a value below 25%. (d) Another test that evaluates the performance of a grease in the presence of water is the mechanical stability in the presence of water. The change in the penetration is assessed and is considered to be due to the absorption of water in the grease. Grease is contaminated and thoroughly mixed with 10% of water and is subjected to 100,000 strokes prolonged cone penetration as per ASTM D217 and the roll stability as per ASTM D1831. The change in the penetration of the greases after these tests with 10% water is assessed and reported. (e) The EMCOR test is a widely-used test for the assessment of the corrosion prevention property of the grease in a bearing. The test is done in an actual bearing filled with grease and kept immersed in water (distilled, synthetic sea water, tap water, or process water as per requirements). The test conditions are simulative of the ability of the grease to stay in place withstanding the shearing due to the action of the bearing rotation, while preventing corrosion on the surface. The test was developed with the bearing running immersed in static water

- 36 VOLUME 80, NUMBER 1

for a period of a week as per IP220, ASTM 6138, ISO 11007, or DIN 51802.

However it was realized that this test does not correlate with conditions of flowing water existing in many applications where the grease tends to be washed out. So a water washout option was developed and it is a part of the new ISO 11007 standard. Bearings after the test are rated for the corrosion on the inner side of the outer race of the test bearings and rated from 0 to 5. “0” stands for no corrosion while “5” indicates very severe corrosion.

The rating procedure remains the same for both the standard EMCOR test and the washout option on the EMCOR machine.

5.0 PRESENT STUDY: The present study was carried out since it was realized that using the standard EMCOR test method using bearings immersed in water was no guarantee that the grease will perform well in service in bearings with a constant ingress of water. Some field analyses revealed that a “0” rating in this test did not mean that the grease will meet the requirements of plant performance especially in steel plant roll neck bearings in hot strip mills where a constant flow of cooling water passes through the jacket of the bearings. This causes the grease to get emulsified as well as washed away due to the constant action of the water.

So it was decided to evaluate several greases with known passing EMCOR performance and evaluate the same greases with the modified EMCOR test procedure.

This would enable insight into whether there was any correlation between the two. Also a good assessment of the grease performance was possible, to separate out the good performers from the ones that could not stand the washout test. The water washout test data was also included for all these greases.

6.0 DESCRIPTION OF EMCOR TEST RIG An EMCOR rig is used for the the dynamic anti-rust test studies on various greases. This rig is popularly used to characterize the corrosion resistance properties imparted by the greases especially in conditions where water ingress occurs in bearings or there is condensation of moisture which ultimately gets deposited on the bearing parts. There is a requirement for the grease to prevent rusting of the bearing surfaces to maximize its

bearing life. This test has been popularly used for over 40 years to measure the ability of a grease to protect a bearing from corrosion even in the presence of water.

The test assesses the ability of the grease to prevent rust on the bearing, specifically the inner surfaces of the outer race of the bearing.

6.1 SKF Grease Test Rig EMCOR: As shown in

Figure 1, it consists of a ground plate (3) on which eight polyamide housings (5) are mounted. A shaft protected with a nylon coating (4) carries the test bearings (7) and is driven by an electric motor (2).

The test bearings are specially-treated 1306K/236725 double row self-aligning ball bearings. The bearings are washed carefully, filled with the appropriate quantity of test grease and fitted on the shaft with the help of a nylon sleeve and nut. The seals are fitted and the specified quantity of water is introduced into the housings. The bearings are placed in the housings and the housings are closed and sealed. The test is run in the following sequence after charging of the water (10 ml on either sides of the bearing). The rotational speed of the shaft is kept at 80 rpm and no load is applied.

Day1: 8 h run,16 h stop Day2: 8 h run,16 h stop Day 3: 8 h run, then stop for 108 hours(over four days) after which the the bearings are dismounted, taken apart, washed, evaluated and rated. The rating is done on the inner surface of the outer race (ring) of the test bearing as shown in Figure 3 and Figure 4. An example of various ratings of the test bearings is shown in Figure 5.

The degree of rust is an indication of the corrosioninhibiting property of a grease. This test method is standardised to the international ISO 11007, ASTM D6138, German DIN 51802, Great Britain BS 2000 pt 220 (IP 220), Sweden SIS 155130 and France NFT 60-135.

The new international standard (published in 1996) contains contemporary, modified and internationally approved procedures to further increase test precision.

The test can be run to test greases as well as oils, and variations can be made with regard to the test medium.

Instead of distilled water, brine(synthetic sea water simulation), tap water or process water can be used

- 37 NLGI SPOKESMAN, MARCH/APRIL 2016

Alternatively, the machine can be slightly tilted to test the corrosion-inhibiting properties of a lubricant when water flows through the housings and so washes out the corrosion inhibitors – the so-called SKF EMCOR washout test (optional). This test as per the SKF standard method is for the determination of water washout rust prevention provided by a lubricating grease. This corrosion test is a useful guide to the protection provided by lubricating grease in the event of a bearing becoming constantly contaminated by water ingress. The use of flowing water in place of the standard laboratory test appears to lead to the failure of greases with watersoluble corrosion inhibitors. [Comment: the use of the word “static” is probably confusing since the EMCOR test is commonly referred to as a “dynamic” test due to the rotation of the bearings during the test. This as opposed to the ASTM D1743 and D5969 corrosion tests which are considered “static” since the bearings don’t rotate during the test.]

6.2 SKF Grease Test Rig EMCOR with the wash-out test: The test rig used is the same device as the standard EMCOR (as described before) with some options as shown in Figure 2 such as the peristaltic pump (1) feeding and outlet pipes (3) and (4) and overflowing container (2). The mechanics is inclined so that an angle from the horizontal of 1,5° is formed and placed in a overflow container (2) to collect test fluid if necessary.

The peristaltic pump (1) pumps test fluid through the feeding pipes (3) into the plummer blocks. Via the outlet pipes (4), the fluid flows out of the plummer blocks. The test machine with the washout option should follow additional guidelines to enable the running of the test.

1. Peristaltic pump : It should be calibrated to ensure flow rate of 2.08 ml per minute ( 1 litre for 8 hour period,or 3 litres during the entire running phase of test)in each channel.

2. Fit adaptors to the bearing housings and ensure drain is free from contamination.

3. Fill the peristaltic pump lines with test fluid and prepare sufficient reservoir of supply test fluid and drainage for the test.

4. The test procedure remains the same except that

each test bearing filled with grease will be exposed 3 litres of test fluid over running time of the entire test procedure during the running of the motor, as opposed to just 20 ml test fluid with the staandard test. The rotational speed of the shaft is kept at 80 rpm and no load is applied. The rating procedure remains the same.

7.0 OBSERVATIONS AND ANALYSIS OF TEST RESULTS: Seven different greases were selected for EMCOR studies without and with water washout. Distilled water was used for the present studies. The selection of these commercial products was done varying various factors like base oil viscosity, type, soap chemistry and presence of corrosion inhibitors. Most of the greases were selected so that the standard EMCOR (IP220) test yielded a passing result, and one of the greases was selected with a marginal fail result to assess if its water washout result varies due to the effect of the washout. The post-test analysis of water was carried out to get information about the mechanism of corrosion protection during the test.

EMCOR test with water washout is reported to be more severe test due to presence of larger quantity and fresh charge of water. It is expected in the case of a test with water washout, the following will affect the performance significantly as compared to a standard IP 220 EMCOR test.

(1) In case of a standard EMCOR test, it is expected that a corrosion-inhibiting film that forms during the initial phase of test remains intact preventing the water and the presence of metallic ions that may cause galvanic corrosion from having any detrimental effect on the surface. The strong film that forms during the initial phase of the test may be enough to protect the surfaces.

(2) In case of a water washout test, since a significant amount of fresh water flows continuously through the bearing, due to the mechanical shearing as well as the leaching of the additives and washing out of the oil film, it is expected that corrosion inhibition additive or the oil film that forms may have to be constantly replenished for the grease to give a good performance in this test.

Keeping this in consideration, the greases were

- 38 VOLUME 80, NUMBER 1

evaluated on the Standard IP 220 EMCOR Test and Modified EMCOR test with water washout. The table with the results of the EMCOR test, the grease composition and the post-test analysis data is given below.

[How were the pH measurements taken? Was a sample of water left in the EMCOR rig at end of test measured? Was the water collected from the whole test and the pH measured at the end?]

- 39 NLGI SPOKESMAN, MARCH/APRIL 2016

7.1: ANALYSIS OF TEST RESULTS Lithium complex greases (No. 1 & 7) -These greases do not contain any corrosion inhibitor. The EMCOR values for both lithium complex greases were found to be (0,0) without water washout. It seems that the film formation due to heavy base oil can protect surfaces in the EMCOR Standard IP 220 test. However, significant corrosion was found in EMCOR test with water washout test (i.e rating of (5,5)), which suggests that the film does not remain intact with the constant ingress of water causing corrosion. [Comment: if the results were from duplicate runs, this should be reflected in the table above. For example, the table shows a rating of “5”, whereas in the description here the author refers to a rating of “5,5”.]

Lithium base greases ( No. 2, 3, & 6) - Grease No. 2 & 6 with similar consistency of NLGI Grade 3 exhibited similar behavior in EMCOR test conducted without (0,0) or with water washout (0,3), indicating that this higher consistency plays a role. Grease No. 2 had Corrosion inhibitor, whereas Grease No. 6 had none. Among lithium base greases, only grease No. 3 was an NLGI grade 2 and the EMCOR results for this grease remained the same with or without water washout i.e (2,2), which was not satisfactory.

Polyurea (Grease 4) and [calcium?] sulphonate complex greases(Grease 5) – Both of these greases are known to have excellent anti-corrosion properties, which is verified by their identical EMCOR ratings (0,0) with or without water washout. Their mechanisms of corrosion protection are on account of their intrinsic chemistry. In the case of polyurea (Grease 4), the absence of metal ions is reported to be responsible for corrosion protection, which inhibits the galvanic potential formation leading to corrosion. In the case of calcium sulphonate grease, the basic chemistry is responsible for corrosion protection.

[Comment: Can the author provide any more detail on why this is so?] This grease is manufactured using water which enables its structure to be developed. The grease is reported to have excellent corrosion protection as well as retention of mechanical stability when evaluated in the presence of water.

To explain the above findings, the following parameters should be considered – a) Consistency of the grease – the higher the consistency of the grease, the better will be the film formation on the surface. From the experiment, it appears that better results in static EMCOR test can be expected for harder greases. Typical case of Lithium base greases No. 2, 3, & 6. [Is it not also possible that the higher consistency means less water is incorporated in the grease, or it repels the water better? Is there any evidence that there is better film formation?] b) Base oil viscosity – Greases prepared with heavier base oil viscosity may result in better film formation on the surface, ensuring better performance for EMCOR test both in the static and with water wash out. [Comment: Both of the greases with the highest base oil viscosity also were the two greases that the author says have excellent anti-corrosion properties.

Couldn’t this be the reason for the better results instead of the higher viscosity?] c) T ype of the soap and presence of the anti-corrosion additive at the site of application – Most of the soaps are polar in nature. Therefore, they compete for metal surface with polar additives. Secondly, some soaps are known to perform better in the presence of water [10] , for example sulphonate and polyurea greases. Increase in pH of water after the EMCOR test for sulphonate grease is an indicator of strong interaction of water with sulphonate grease.

However, it should also be kept in mind that presence of other additives such as EP, AW and AO can also react with water or may leach out and can alter pH of water significantly. In the case of Grease 5 (calcium sulphonate), the effect of the basic chemistry of the grease and its strong interaction with water overshadowed the effect of other additives.

8.0 CONCLUSIONS: (1) EMCOR Water washout test is comparatively much more severe than the Standard IP 220 EMCOR. (2) The test is able to distinguish between different greases which offer mild to moderate corrosion protection to those that offer a high degree of protection.

- 40 VOLUME 80, NUMBER 1

(3) The results obtained in the test correlates well with the field performance in terms of the greases which are known to give good performance in field conditions like Calcium sulphonate and the Polyurea greases. [Can any more information be shared on field performance of these specific greases?]

(4) The mechanism of corrosion protection varies from grease to grease based on various factors. The study yields a good insight into the factors that should be borne in mind for formulation of a grease to meet the performance requirements whenever there is ingress of water or moisture in the rolling element bearings. Primary factors such as the instrinsic chemistry of the grease and corrosion inhibitor additives play a key role, but it may be necessary for greases to be fortified by secondary factors like higher base oil viscosity, mechanical stability retention in presence of water, etc. [Further study or additional data is probably necessary to show this correlation.]

(5) Calcium sulphonate and polyurea chemistries work well in offering good corrosion protection in a static EMCOR test and a water washout EMCOR test. This may be due to their inherent chemistries. Calcium sulphonate is known to work well as a corrosion inhibitor, whereas polyurea greases likely offer some corrosion protection since these do not have any metallic ions which could promote the galvanic effect.

(6) There was a sharp increase in basicity of the calcium sulphonate grease during washout test, which explains the good corrosion performance. [How?] In case of the others, the change of pH was not so significant(ranging from weak acids to weak base), and may also be due to the depletion effect of other additives present in the grease such as antiwear, EP or antioxidants.

(7) The test methods used may not fully correlate with conditions present in a hot rolling mill bearings where

the grease-lubricated bearings are subjected to high temperature conditions which may increase the severity of test. The polyurea and calcium sulphonate greases are also known for their high temperature performance, so the correlation with field conditions was still valid. [Are they known for good protection against rust at high temperature?

Or just better life (more oxidation resistance) at high temp?] However, this could be a future course of action for a study.

9.0 FIGURES

- 42 VOLUME 80, NUMBER 1

- 43 NLGI SPOKESMAN, MARCH/APRIL 2016

- 44 VOLUME 80, NUMBER 1

10.0 REFERENCES 1. R. F. McKibben, D. M. Forinash, Relating Humidity Cabinet Life of Lubricants to Their Service Life, ASLE Transactions 6, 233-238 (2008).

2. SKF Tech tip, TT 09-004, March 2009 3. Timken Automotive TechTips, Vol.3 Issue 5 , 2009 4. P M Lugt, “Grease lubrication in bearings”, Wiley Tribology Series, 2013.

5. P.M. Lugt A Review on Grease Lubrication in Rolling Bearings, , Tribology Transactions, 52: 470-480, 2009 6. ”H2O, friend or foe?”, Axel Christiernsson, Lubrisense White Paper 08, 2008 7. Johan Leckner, Water + Grease = fatal attraction?, Proceedings of 25th ELGI Annual General Meeting, 2013.

8. Jim Fitch, How Water Causes Bearing Failure, Noria Corporation, Machinery Lubrication (2008) 9. Russel Folger, David Novak, Jerry Rhodes, “Bearing Killers, Preventing the top causes of bearing damage”, Machine design, February 2014.

10. David Authier, Alexia Herman, Calcium Sulphonate Carbonate Grease: A solution to water resistance, Presented at the ELGI annual meeting, 2013.

10.0 : ACKNOWLEDGEMENTS The authors are thankful to the management of Indian Oil Corporation Ltd, R&D Centre, Faridabad for granting permission to present these findings.

- 45 NLGI SPOKESMAN, MARCH/APRIL 2016

NLGI Industry News Please send all industry news, events, employment news and press releases to Marilyn Brohm (Your company does not have to be an NLGI member to post items.)

ChemPoint Signs Master Distribution Agreement with Dow Corning for Molykote® Specialty Products in the U.S. and Canada BELLEVUE, Wash. – March 8, 2016 – ChemPoint.com, Inc. (“ChemPoint”), a subsidiary of Univar Inc. (NYSE: UNVR), and a leader in the marketing, sales, and distribution of specialty and fine chemicals, today announced that it has signed a master distribution agreement with Dow Corning, a global leader in silicone-based technology and innovation, for Molykote® specialty products. Under the agreement, effective March 1, 2016, ChemPoint will manage order placement, fulfillment, and technical support for Molykote® brand compounds, greases, pastes, anti-friction coatings, dispersions, and oils for the industrial assembly and maintenance market in the United States and Canada.

To read the complete press release visit: https://www.nlgi.org/news-and-events/industry-news

BECHEM Lubrication Technology, LLC Adds to its Growing Sales & Market Development & Engineering Team BECHEM announces that Dustin Greiner has joined the BECHEM Sales & Application Engineering team. After graduating from Ferris State University with a Bachelor of Science Degree in Elastomer Engineering, Dustin has worked in the industrial market applications of sealing technologies from various facets. With over 10 years at FreundenbergNOK Sealing Technologies and Dichtomatik Americas L.P., he has worked in an array of areas in quality, supplier development, commodity management, and sales engineering.

To read the complete press release visit: https://www.nlgi.org/news-and-events/industry-news/

Phillips 66 Lubricants Announces Consolidation of its Brand Portfolio

Lubricants Supplier Commits to Concentrated Marketing Support for Phillips 66® and Kendall® Motor Oil HOUSTON (February 25, 2016) In an effort to strengthen relationships and drive strategic growth, Phillips 66 Lubricants, one of the largest finished lubricants suppliers in North America, today announced it will consolidate its Lubricants portfolio into two brands, Phillips 66® and Kendall® Motor Oil, beginning July 1, 2016. According to the company, transitioning away from a tri-branded strategy will help to elevate the profile of Phillips 66 Lubricants as a national lubricants supplier and better position it for the future. As a result of the consolidation, Phillips 66 Lubricants will optimize its product portfolio mix and develop a full line of lubricants products for every need under the Phillips 66 brand. To read the complete press release visit: https://www.nlgi.org/news-and-events/industry-news/ - 46 VOLUME 80, NUMBER 1

AXEL Americas Completes Multi-Million Dollar Expansion of its Rosedale, Mississippi Facility

New production and filling lines increase capacity by over 17 million pounds February 22, 2016 -- Rosedale, MS-- AXEL Americas, one of the leading manufacturers and suppliers of lubricating greases in the US, announced today that it has completed its highly anticipated expansion of its Rosedale, Mississippi facility. This plant expansion at the ISO and TS Certified facility comes as a response to growing customer demand for its industrial and automotive greases, which are supplied to multinational companies and large distributors in the Americas.

To read the complete press release visit: https://www.nlgi.org/news-and-events/industry-news/

Quakertown PA; February 17, 2016 - Bill Tuszynski is pleased to announce the formation of The Unami

Group (www.unamigroup.com), a business consultancy and sales agency serving the specialty chemical industry with a focus on lubricant raw materials and additives. A company strength, is new business development both by aiding clients in identifying and commercializing new technologies and products and in finding new applications for existing products. The company provides services in market research, competitive intelligence and technology assessment. The Unami Group is also serving as sales agent for Functional Products, Inolex Chemical Company and Ivanhoe Industries at selected accounts. Prior to forming The Unami Group, Tuszynski served as a Managing Partner at Ivanhoe industries. He is a member of STLE and the company is a member of NLGI. To read the complete press release visit: https://www.nlgi.org/news-and-events/industry-news/

Matt Mannette Joins MidContinental Chemical Company - Industry veteran assigned to southeastern region of USA February 12, 2016 - Olathe, KS - MidContinental Chemical Company, Inc. (MCC) announces the

appointment of Matt Mannette as District Manager for their southern region of the USA. Matt will play a key role in developing effective strategies and tactics to expand both fuel and lubricant additive sales in this assigned geography. To read the complete press release visit: https://www.nlgi.org/news-and-events/industry-news/

First Major Milestone Achieved in Croda’s $170m Investment in Renewable Manufacturing EDISON, NJ (January 27, 2016) –With the steel work that will house the main process reactor in place at its

Atlas Point manufacturing site in New Castle, Delaware, Croda International Plc, who make specialty chemical ingredients that enhance everyday consumer and industrial products, came a step closer to completing the first plant of this type in North America that will manufacture 100% renewable non-ionic attractants.

To read the complete press release visit: https://www.nlgi.org/news-and-events/industry-news/

- 47 NLGI SPOKESMAN, MARCH/APRIL 2016

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