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July 1, 2008
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Come On Aboard: Solving Problems In Ethanol Plants

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This forward-thinking supplier is taking the type of solutions that improve efficiency and help reduce operating costs directly to end users.

SEPCO® (Sealing Equipment Products Co., Inc.), a manufacturer of fluid sealing products headquartered in Alabaster, AL, has taken an innovative approach to providing sealing solutions to the ethanol industry. World demand for alternative fuel sources has produced rapid growth and expansion of ethanol facilities, all of which has presented new demands and challenges for support companies that serve this burgeoning industry.

To meet these new challenges head-on, SEPCO has dedicated full attention to the developing bio-fuels industry by using its Mobile Ethanol Support Unit—otherwise known as “MoE”—as a tool to share its products and programs through instruction, demonstration, plant support and training.

On-site with MoE
The Mobile Ethanol Support Unit takes SEPCO support programs directly to ethanol plants. The unit serves as a classroom for hands-on training of fluid sealing products which are used in operations. Ethanol plant employees are trained on SEPCO mechanical seals that include, but are not limited to, the hot oil Seal (HOS), double tandem pumper (DTP), cartridge grease seal (CGS) and many other fluid sealing products.

Another primary function of the MoE unit is to serve as a central point of support during plant outages and start-ups by providing inventory and technical assistance at the site. The MoE also can be used as a base of operations in performing plant equipment inventories/ surveys and developing fluid sealing applications to maximize equipment operational performance. Totally self-contained, the MoE has its own computer system, audiovisual equipment and graphics and product literature. Working models of pumps for training are onboard, as is an inventory of SEPCO fluid sealing products.

According to a SEPCO spokesman, this mobile support unit has been very well received by end users. Scheduling information may be obtained by calling the company. LMT

Sealing Equipment Products Co. (SEPCO®) 
Alabaster, AL

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July 1, 2008
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Part II: Using Oil Mist On Electric Motors

0708_oilmist_img1As the reader will recall from Part I of this two-part article, dry sump oil mist on electric motors represents wellproven technology. In the mid-1960s, oil mist—a mixture of 200,000 volume parts of clean and dry plant or instrument air with one part of lubricating oil—gained acceptance as the ideal lubricant application method on rolling element electric motor bearings in several major United States oil refineries. Since then, this lubrication method has gained further acceptance at hundreds of reliability-focused process plants in this country and overseas and, as of the late 1990s, many thousands of electric motors were being lubricated by dry sump oil mist. Remember: Whenever oil mist is used for pump lubrication, its extension to cover electric motor drivers will be very inexpensive.

The right bearing and correct installation
Oil mist cannot eliminate basic bearing problems— it can only provide one of the best and most reliable means of lubricant application. (Refer again to Fig. 1.) Bearings must:

  1. Be adequate for the application, i.e. deep groove ball bearings for coupled drives, cylindrical roller bearing to support high radial loads in certain belt drives, or angular contact ball bearings to support the axial (constant) loads in vertical motor applications.
  2. Incorporate correct bearing-internal clearances.
  3. Be mounted with correct shaft and housing fits.
  4. Be carefully and correctly handled, using tools that will avoid damage.
  5. Be correctly assembled and fitted to the motor caps, carefully avoiding misalignment or skewing.
  6. Be part of a correctly installed motor, avoiding shaft misalignment and soft foot, or bearing damage incurred while mounting either the coupling or drive pulley.
  7. Be subjected to vibration spectrum analysis. This will indicate the lubrication condition in regard to lubricating film, bearing condition (possible bearing damage) and general equipment condition, including misalignment, lack of support (soft foot), unbalance, etc.

0708_oilmist_img2Additional considerations when converting electric motors that are already in use 
When converting operating motors from grease lubrication to dry sump oil mist lubrication, consider the following measures in addition to those mentioned in the previous list:

  1. Perform a complete vibration analysis. This will confirm pre-existing bearing distress and indicate if such work as re-alignment and/or base plate stiffening is needed to avert incipient bearing failure.
  2. Measure the actual efficiency of the motor. If the motor is inefficient, consider replacing it with a modern high efficiency motor, using oil mist lubrication in line with the aforementioned recommendations. This will allow the capture of all benefits and result in greatly enhanced return on investment.
  3. Last, but not least, evaluate if the capacity of the motor is best suited for the application. “Best suitable” typically implies driven loads that represent 75% to 95% of nominal motor capacity. The result is operation at best efficiency. Note that converting an overloaded, hot-running electric motor to oil mist lubrication will not usually be of economic benefit and will lead to marginal improvement at best.

Regarding explosion-proof motors
Although explosion-proof motors have been successfully lubricated with pure oil mist for at least three full decades, questions are occasionally raised as to whether explosionproof (XP) electric motors are suitable for this mode of lubrication.

Dealing with codes and practices…
The selection, operation and even maintenance of industrial equipment in the developed countries often are influenced by industrial standards, regulatory agencies and certain applicable codes. Major companies, though, superimpose their own design standards, specifications and best practices. It can be shown beyond any doubt that many of these practices reflect advanced thinking that is often years ahead of current regulatory edicts. Nevertheless (more recently), some of these practices have come under scrutiny. In the case of oil mist applied to explosion-proof electric motors, the scrutiny was not prompted by any safety incidents. Rather, it has been brought on by the fact that we live in litigious times and lawsuits are costly.

It appears that the acceptability of dry sump oil mist on explosion-proof motors relates to third-party approval and the original equipment manufacturer’s certification of the motor. For years, users have provided all except their explosion-proof electric motors with a small (3 mm) weep hole and have given XP-motor drains closer attention. The latter are furnished with either an explosion-proof rated vent or a suitably routed weep hole passage at the bottom of the motor casing or lower edge of the end cover. Intended to drain accumulated moisture condensation, the vent or weep hole passage will allow liquefied or atomized oil mist to escape. Note, however, that explosion-proof motors are still “explosion-proof” with this passage. (For example, Baldor • Reliance Motors [formerly Reliance Electric] tackwelds an explosion-proof “XP-breather drain” to the motor brackets. The suitability of this line of motors for Class 1, Group C and D locations was specifically re-affirmed by the manufacturer in July of 2004.)

Not being familiar with dry sump oil mist, though, causes some motor manufacturers and third party validation providers to take the position that explosion-proofmotors lose this “listing” once any modifications are made to the motor.

Highlighting oil mist for XP motors 
As the name implies, explosion-proof motors are intended for use in hazardous areas. The majority of hazardous areas in hydrocarbon processing facilities are designated as Class 1, Division 2, Groups B, C and D.

The Class 1 area designation indicates that either a flammable liquid or vapor or both are present. (Class 2 designations are reserved for areas where combustible metal, carbon fines or other combustible dusts such as grain flour or plastic are present).

The “Division” label is used to better describe the probability of flammable gases or vapors being present in a Class 1 or Class 2 location.

  • Division 1 is intended for locations where ignitable concentrations of flammable gases or vapors can either exist under normal operating conditions, or might be present while the equipment is undergoing repair or maintenance.
  • Division 2 defines the area or location where the flammable liquids or vapors are possibly present and/or:
  1. Normally confined within closed containers or closed systems and are present only in case of accidental rupture or breakdown of such containers, or in case of abnormal operation of equipment; or
  2. Where ignitable concentrations are normally prevented by positive ventilation; or
  3. An area adjacent to a Class 1, Division 1, location.

The “Group” designation has four subgroups, or gas groups—appropriately called Groups A, B, C and D. Determining the proper group classification for flammable gases and vapors requires monitoring and describing explosion pressures and maximum safe clearances between parts of a clamped joint under certain prescribed conditions whereby a test gas is mixed with air and ignited.

The test values obtained for a reference gas are compared with the gas or gases of interest; these must now be tested under the same conditions. Gases having similar explosion pressures are grouped together. However, Groups C and D contain the majority of flammable gases and vapors. Group A only contains acetylene, while Group B generally contains hydrogen and other hydrogen-rich gas mixtures, plus a few other flammable gases.

An important concession is made by the National Electrical Code (NEC) for equipment used in Division 2 areas, where flammable gases are normally not present, i.e. a refinery or petrochemical plant under normal conditions. If they meet stipulated criteria, the NEC allows the use of certain types of devices and materials that may not be listed by third party, or “listing” agencies. For instance, these exceptions to the NEC’s general code requirements permit general-purpose enclosures if the electrical current interrupting contacts are:

  1. Immersed in oil; or
  2. Enclosed within a chamber that is hermetically sealed against the entrance of gases or vapors; or
  3. In non-incendive circuits; or
  4. Part of a “listed” non-incendive component; or
  5. Without make-and-break or sliding contacts.

Except for the above exclusions, the National Electrical Code/NFPA 70 (“NEC”) requires that all electrical apparatus installed in classified (hazardous) areas must be approved for use in the specified Class and Group where it is to be used. Once an electrical apparatus is described as “explosion-proof,” it is implied that the device has been evaluated and approved for use in a particular Class and Group. The evaluation or approval agency was earlier called a “third party.” In the United States, third parties include Underwriters Laboratories (UL), Factory Mutual (FM) and others. Once an apparatus or device has been evaluated and approved for a particular Class or Group, it is labeled “listed” by the agency.

In most Class 1 Division 2 hazardous areas, the electric motors are not, and do not need to be “explosion-proof.” The overwhelming majority are non-arcing induction motors that meet the requirements of the applicable and allowed exceptions. These non-explosion- proof motors can be adapted for dry sump oil mist lubrication by simply connecting oil mist supplies and vents to the existing connections used with the explosion-proof units. Because these motors are non-arcing and an explosion-proof housing is not needed for Division 2 service, the case drain fitting can be removed and a drain can be installed without in any way affecting the suitability of the motor for Division 2 service.

Safety of XP motors for Class 1 Division 1 service
Regrettably, some listing agencies in the United States seem to believe that oil mist applied to the bearings makes the motor different from what was originally approved. Not understanding oil mist, they take the position that by in any way adapting plugs and drain fittings to oil mist application, mist venting and mist draining, the safe clearance requirements between clamped components used in the original design requirement may have been changed. Therefore, they consider the approval listing void and claim the motor is no longer suitable for use in Class 1 Division 1 service. In view of this stance taken by third parties, even a major provider of oil mist systems in the United States does not allow its employees to make on-site modifications to convert or connect an explosion-proof motor to oil mist. That said, a number of clarifications are in order here.

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First and foremost is the fact that explosion-proof motors were successfully converted to oil mist lubrication by undisputed best-of-class petrochemical companies three decades ago and have since given safe and reliable service. These forward-looking companies, for whom safety is of utmost importance, correctly reasoned that all electric motors, regardless of classification, were assembled and being operated in an ambient environment. Thus, they always are filled with ambient air; certainly none of these motors are provided with mechanical seals that would positively prevent an interchange or communication between motor-internal air and the surrounding ambient air. Should an explosive gas mixture prevail in the vicinity of such motors, there would now exist the possibility of the motor ingesting this explosive gas mixture. If, on the other hand, such a motor were filled with the demonstrably non-explosive oil mist at slightly higher-than-atmospheric pressure, the probability of the motor becoming filled with an explosive gas mixture would be greatly reduced. In other words, knowledgeable user companies have long recognized that an oil-mist-lubricated motor operating in a Class 1 Division 1 environment is safer than a conventionally lubricated electric motor operating in the same environment.

It also may be argued that item 2, and possibly one or two other items cited as exclusionary by NEC, allow the user to reason that oil mist existing at a pressure higher than atmospheric complies fully with the spirit of the listed exclusions.

References

  1. Bloch, Heinz P., and Alan Budris, (2006), Pump User’s Handbook: Life Extension, Fairmont Press, Inc., Lilburn, GA, 30047; ISBN 0-88173-517-5, pp. 265-290
  2. Bloch, Heinz P., and Abdus Shamim, (1998), Oil Mist Lubrication: Practical Applications, Fairmont Press, Inc., Lilburn, GA, 30047; ISBN 0-88173-256-7, Fig. 9-7, p. 109
  3. Shelton, Harold L., “Estimating the lower explosive limits of waste vapors,”Environmental Engineering, May-June 1995, pp. 22-25
  4. Lilly, L.R.C., (1986), Diesel Engine Reference Book, Butterworth & Co., London, U.K., ISBN 0-408-00443-6, p. 21/3

Contributing editor Heinz Bloch is the author of 17 comprehensive textbooks and over 340 other publications on machinery reliability and lubrication. He can be contacted at:hpbloch@mchsi.com

 

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July 1, 2008
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Part II: How Clean Is The New Oil In Your Equipment?

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How much do you know about the blending process and its effect on oil cleanliness? Is that where the trouble starts?

There are many different lubricant blenders in the U.S.—some very large and some small. In this series, the general practices of large, major oil company blenders and some of the medium-size specialty lubricant suppliers are examined.

The blending process
The typical flow through a blend plant is characterized by Fig. 1. The process begins with receiving of the base stocks that are shipped to large facilities by pipeline, barge or rail. Smaller facilities receive base stocks by rail or truck.

Base stocks usually are not filtered before being introduced in the blend tank, but there are some exceptions. One blender company filters all base stocks shipped by barge, rail and truck with a 25 micron filter. Additives come in many package styles, including drums, totes and bulk. They typically are not filtered before being introduced in the blending tank. Hydraulic and turbine oils contain less than 1% additives, so cleanliness is not as important as it is for base stocks

Base stock and additives are introduced in the blend tank and mixed together to make the finished product. Cleanliness targets are set by some facilities for turbine, hydraulic and other oils specified by large customers. The first filtration (which typically is a coarse one, perhaps through a bag filter) is from the blend tank to the finished product tank. The final filtration, which is to achieve a specific cleanliness target, is from the finished product tank into a bulk truck for customer or distributor delivery. Finer filtration also is performed from the finished product tank to the packaging operation.

There is a range of lubrication blenders—from those that provide very little to no filtration and no measurement of lubricant cleanliness, to those that have tight cleanliness specifications to meet specific customer needs. Hydraulic and turbine applications usually require cleaner fluids.

0708_contamination_img2The following are examples of companies that have targeted cleanliness levels on oils shipped from their facilities.

  • A large major supplier of finished lubricants has established a reasonable target of 19/17/14 for its hydraulic and turbine oils. It normally will achieve a cleanliness level of 2 or more ISO codes below the target. This supplier filters with a sock filter from the blend tank to finished product tank, then uses finer filtration from the finished product tank to a truck or packaging line.
  • Another major supplier of finished lubricants has a program for its premium turbine oils. For an additional charge, the turbine oil is guaranteed to have a minimum ISO cleanliness of 18/16/13. (This meets General Electric’s cleanliness specification of 16/13.) This supplier also will guarantee hydraulic oils to an ISO cleanliness of 17/15/11—something that is achieved by having initial filtration with a 13 micron filter going into the product storage tank. This is followed by a 6 micron filtration from the product storage tank to a dedicated tank truck for turbine oils or the drum packaging operation to achieve guaranteed cleanliness targets. In addition, all drums for both the turbine and hydraulic fluids with guaranteed cleanliness are polyethylene plastic to maintain the cleanliness level. In most cases this supplier will be lower than the established cleanliness level.
  • A mid-size supplier of specialty lubricants has a guaranteed ISO cleanliness code of 14/13/11 for its ISO 32, 46 and 68 synthetic oils. This is for only plastic-packaged products (in drums, pails and totes). The main filtering step incorporates a product-holding tank with fine offline line recirculation filtration. This company also does bag filtration from the base stock tank to the blending tank. The fluid is recirculated until the required cleanliness level is attained. The plant has stainless steel dedicated piping that helps meet these cleanliness levels.
  • Another mid-size supplier of specialty lubricants has a program to supply hydraulic fluid for injection molding machines requiring clean fluid. This company supplies the fluid in plastic containers at a guaranteed ISO Cleanliness Code of 17/15/13.

Clean fluid shipped by the lubrication blender will require less or no filtration when it reaches the end user. Remember, though, there is a cost for fluid cleanliness. Some companies charge $.05 to $.20/gallon, which is well worth the cost to get a guaranteed cleanliness. Many blenders don’t measure fluid cleanliness as it leaves the plant and many do just a very coarse filtration—if any. Fluid cleanliness can vary by one or two ISO codes, depending on how it is measured—whether it is with a portable or online counter or sent to a laboratory for evaluation. (Part III of this series will address online versus laboratory particle counting.)

Lubricant evaluation
Do you really know how clean the oil is that you are buying? Is it clean enough for your equipment, especially hydraulics and turbines? With the exception of a few companies, no one publishes data that specifically points to a cleanliness rating for their products. The few that publish this information do so only for specific products. In order to shed more light on the subject through this series of articles, 17 oils were purchased and underwent evaluation for cleanliness and water content along with other oil analysis.

MRT Laboratories of Houston, TX was selected to do all the test work for several reasons, including:

  • The lab’s proximity to sample collection, which minimized shipping;
  • The authors’ experience with the quality of MRT’s work;
  • The fact that this laboratory is ISO 17025-2005 accredited.

The following samples from four of the major lubricant suppliers and one small blender were purchased from Houston-based distributors in five-gallon plastic pails:

  • Four ISO 32 turbine oils
  • Four ISO 46 hydraulic oils and one ISO 32
  • Four ISO 100 R&O circulating oil
  • Four ISO EP 220 gear oil

The following tests were performed on the samples:

  • Particle counts as expressed as ISO 4406 Cleanliness Code with the use of an
    optical blockage counter
  • Karl Fisher Water Coulemetrically
  • Viscosity @ 40 C
  • Acid Number
  • Emission Spectroscopy for 24 metals.

Test protocol
The five-gallon plastic pails were delivered sealed to the laboratory. The pails were agitated, and individual samples were taken from the middle of each. A superclean bottle was used and flushed with four ounces of fluid before being filled. The samples were immediately run in the laboratory

Results

Turbine oils…

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It is interesting to note that the only turbine oil packaged by a blender came from Supplier D; this sample was the cleanest of the group. The others had been packaged by the distributor/marketer. All of these oils were clean and very dry. (Product moisture has not been discussed but it is a very important property of a lubricant and should be monitored.)

Hydraulic oils…

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Supplier E’s product was an off-brand hydraulic oil purchased from an automotive parts store and 30% lower in cost than the premium hydraulic oils purchased through a distributor. There was no viscosity designation on the pail. It was called R&O hydraulic oil. This oil upon evaluation appeared to be used flush oil. It had 24 ppm of iron along with 41 ppm of aluminum. It also contained high levels of silicon, sodium and potassium. This indicated possible coolant contamination. In light of its high particle count and water content, this fluid should not be used in a hydraulic system. How would you know the low quality of such oil unless you ran oil analysis tests? It was observed that the oil was very dark and emitted a pungent odor. Low-viscosity hydraulic oils are not dark in color, nor do they have an odor.

There are many very good lubricants sold by compounder blenders. The evaluation of this low-quality oil should not reflect on the rest of the group. A lesson to be learned from this is that one should buy lubricant from a supplier with whom you are familiar—especially if it is used in a critical application like hydraulics.

Supplier D’s product was the cleanest of the group—and the only one packaged at a lubricant blend plant. The others were packaged by distributors. This is a common practice. Many distributors package their own oils in drums and pails—especially hydraulic and turbine oils. The only other oil that was marginal for a hydraulic system without further filtration was that from Supplier B—it showed a high amount of water and a high particle count, but all other tests revealed it was high-quality oil. The moisture and particles were probably introduced during the packaging process at the distributor.

R&O circulating oils…

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All of these ISO R&O circulating oils (which are used in compressors) were packaged at the blend plant. These oils were clean and dry. Supplier D again had the cleanest oils, but all the others also were high-quality and suitable for usage.

EP gear oils…

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All of the lubricants in the EP gear oil table are ISO 220, which is the most common viscosity grade for most gear reducers. Supplier B’s product was packaged by the distributor. The others were packaged at blend plants. Gear oils are not as clean as turbine or hydraulic oils, but these lubricants in many cases will be clean enough for unfiltered lower speed gearboxes, especially if this oil is added to existing oil in the reservoir, which is probably dirtier. In splash lubrication, the most common lubrication method for gearboxes, bearings also are lubricated by the same oil. Bearings require cleaner oil than gear teeth. This should be taken into consideration when determining the cleanliness targets for gearboxes and in some cases may require filtration to meet those targets.

Conclusion: encouraging results
The first key link in the cleanliness chain was examined by looking at the contaminant levels of various oil types from their respective blend plants. The results were encouraging. The major lubricant suppliers’ oils were clean and dry for most applications. Some suppliers offer further filtration to meet stringent customer requirements, but at an additional cost. This is particularly true for turbine and hydraulic oils where greater cleanliness is required. It also was encouraging to note that of the 17 oils evaluated for water, only four were higher than 100 ppm—and two of those were packaged by a distributor.

As a group, the gear oils evaluated here were not as clean as the other lubricant types. That was expected. They were, however, found to be clean enough for most applications.

One final word of caution: Be familiar with the lubricants you purchase! Use of that low-quality hydraulic oil previously cited could have caused equipment damage. Overall, though, rest assured that there are many reputable lubricant suppliers—both large and small—that furnish quality products. LMT


Contributing editor Ray Thibault is based in Cypress (Houston), TX. An STLE-Certified Lubrication Specialist and Oil Monitoring Analyst, he conducts extensive training in a number of industries. Telephone: (281) 257-1526; e-mail: rlthibault@msn.com

Mark Graham is technical services manager for O’Rourke Petroleum in Houston, TX. Telephone: (713) 672-4500; e-mail: mgraham@orpp.com

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July 1, 2008
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On-Site Infrared Analysis For Lubrication Condition Monitoring Anywhere!

Lubricating fluids degrade over time depending on various external and internal influences, including type and age of equipment, ambient temperature and humidity and degree of use and load on equipment, etc. It is well established that monitoring the health of lubricating fluids is an important and necessary part of high-value machinery maintenance. The traditional approach for determining the condition of these vital lubricants is to take a sample, send it off for analysis at a commercial testing lab, then track trends in changes in key lube parameters over time. When these analyses indicate a problem, corrective actions such as refreshing or changing the lubricant are taken.

0708_lubeanalysis_img1As companies move from preventive maintenance to proactive maintenance, there is increasing interest in onsite lubricant testing because results can be obtained much faster—and they may be more trustworthy. It allows lubrication specialists and maintenance personnel to take decisive action right away. This latter point is important since some of the degradation processes in lubricants occur nonlinearly in time and more quickly than one might expect, which can lead to increased equipment wear or failure. Of course, the ability to use on-site testing equipment is predicated on the ability of the testing equipment manufacturers to make their products straightforward to use and provide valuable information.

A number of analysis methods have made the jump from use by experts off site to routine use by lubrication specialists on site. One technique not making that jump—until now—has been infrared spectroscopy. Infrared has been used for years to evaluate lubricating fluids, but virtually always in off-site commercial labs. Now, though, infrared analysis also is available for use in on-site facilities.

Monitoring critical lubricant parameters
There are several key parameters for which infrared is capable of providing highly accurate information in lubricants including:

  • The level of water present
  • The amount of oxidation and nitration by-products
  • The amount of anti-wear, anti-oxidation and extreme pressure additives remaining

All of these parameters are critical—and some can be measured with other methods. No other technology, however, can provide information on all parameters simultaneously, in less than two minutes. The use of infrared analysis for each parameter will be explored here.

Infrared analysis for water
The amount of water that is present in lubricants is critical to the performance and longevity of the lubricated equipment. Lubricant properties affected by the presence of water include viscosity (measure of the oil’s resistance to flow), specific gravity (density of the oil relative to that of water), and the surface tension (a measure of the stickiness between surface molecules of a liquid). All of these properties are important for the ability of the oil to coat, lubricate and protect the critical mechanical clearances. In addition, the presence of water can accelerate additive depletion and contribute to chemical degradation mechanisms such as oxidation, nitration and varnish formation.

0708_lubeanalysis_img2The ability to measure water on-site provides a substantial benefit to ensure accuracy of results. Off-site analysis for trace water may be compromised due to variability of water concentration introduced by storage, transportation or shipment of a sample. Furthermore, some lubricants contain de-emulsifying additives that cause microscopic water droplets to separate concentrate in layers at the bottom and sides of sampling containers. This de-emulsifying action takes time to occur and can cause large variations in analytical measurements. Furthermore, lubricant samples can lose water due to evaporation and loss to the sample container walls. To obtain an accurate picture of the amount of water present, measurement should be made soon after the sample is pulled from the machine.

Analytical determination of water in lubricants typically is carried out using the well-established Karl Fischer (KF) coulometric titration. KF has some practical drawbacks for on-site analysis including complicated sample preparation, the use of hazardous and expensive chemical reagents and length of time required to perform the analysis. With these issues in mind, KF analysis is still considered the “gold standard” method for analyzing water in oil because it provides accurate and precise answers. Under ideal conditions, Karl Fischer has an accuracy of 3-5% for prediction of water in lubricants.

While infrared spectroscopy provides an easy means to measure water, only recently has this technology been able to provide the accuracy and range desired by the lubrication industry. New developments in the ability to use FTIR spectroscopy to carry out customized methods have now made the analysis of low levels of water in lubrication possible, which overcomes earlier technical difficulties. These new methods, coupled with a dedicated on-site infrared analyzer, measure the concentration of water in mineral-based oils with an accuracy and range equivalent to the Karl Fischer method. FTIR allows this measurement to be carried out on a single drop of lubricant, requiring no hazardous or expensive reagents, and it takes significantly less time to complete than KF.

Methods to directly measure water in mineral oils via infrared spectroscopy have been available for over 30 years. For example, the ASTM 2412E method was originally designed for use with motor oil. Routinely containing 1000 to 2000 ppm of water, motor oil has additives that solvate the water into the oil. The methods developed to measure water in these oils by infrared analysis were targeted at large concentration and had correspondingly large errors associated with them. Other lubricants (such as turbine oil) solvate significantly less water—typically it’s 50 to 100 ppm. In these lubricants, higher levels of water form small droplets that eventually settle to the bottom of the turbine oil. If the ASTM 21412 method for water is used for turbine oil, measurement variability of up to 40% on replicate samples is observed.

0708_lubeanalysis_img3The primary reason the conventional method for measuring water in oil by FTIR produces a high error in turbine oils is water separation—water separates into small droplets in turbine oil. These small droplets scatter instead of absorb infrared light, and only the light that is absorbed contributes to the measurement of water. Over time, it became clear that a means of stabilizing the water in the oil would be needed to reduce variability.

Water stabilization method for infrared analysis
A new method (patent pending) has been developed for the measurement of water in turbine oil. This method, reflected by the data in Table I, uses a surfactant to distribute and stabilize the water in the oil, creating a stable emulsion with uniform water droplet size. Addition of approximately 3% of a premixed non-ionic polyethylene oxide based surfactant blend and gentle mixing effectively stabilizes the water in the lubricant.

Determining degree of oxidation and antioxidant depletion
Oxidation is the most significant cause of lubrication breakdown. It occurs when the hydrocarbon components of the lube combine with oxygen to form a wide range of harmful by-products including ketones, aldehydes and carboxylic acids. Once these compounds form, they in turn combine with other species in the lube and form even more unwanted degradative products. Virtually all of the chemical species that result from oxidative processes can be detected and measured by infrared analysis (Fig. 1). Early detection of these species allows for remediation action to slow down the oxidation process.

The phenolic and aminic antioxidants in lubricants function as preservatives that prevent the oil from oxidizing. Oxidation causes lubricants to quickly lose viscosity and the wetting characteristics that protect metal contact surfaces and prevent wear. Oxidation arises from a combination of sources—including elevated temperatures, extreme pressures, high shear conditions and the presence of water and metal particles—and is accelerated by electrostatic sparking, particularly in certain gas turbine systems. Although antioxidants inhibit the formation of these decomposition products, once the antioxidants are consumed, oxidation accelerates exponentially and at a certain critical point corrective action has negligible benefit. On-site analysis offers a significant benefit in this regard by ensuring that both the antioxidant levels and the amount of oxidation present are known in time for corrective action to be taken before the critical point is reached.

Infrared compared to other oxidation-measuring technology
Infrared analyzers require a drop of neat oil—with no sample preparation. Voltammetric systems require careful pipetting techniques and an extraction step involving an electrolyte solution. The extraction step used in voltammetric systems assumes that all of the antioxidants are extracted from the oil into the electrolyte solution. However, extraction efficiencies are variable for additives in oils. Ranging from 50-90%, these efficiencies may result in 10-50% of additives being left in the oil after extraction, and thus not being measured. Moreover, voltammetric electrodes require maintenance, such as conditioning in buffer solutions. Metal particles, water or organic salts (i.e. ionized carboxyls such as copper carboxylates) will not interfere with the antioxidant measurements using infrared spectroscopy.

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Conclusion
Real-time, on-site FTIR analysis offers a number of potential— and important—benefits to lubrication specialists and maintenance personnel. They include the ability to:

  • Analyze lubricants more frequently, especially when previous analyses indicate that machinery needs more careful monitoring… When the performance of lubricating fluid begins to degrade, or if earlier analyses indicate the presence of a mechanical problem, it is important to monitor the lubricant more frequently because the process of deleterious change can accelerate rapidly.
  • Help reduce machinery wear caused by rapid oil breakdown and to detect problems that could cause catastrophic failures… For example, an anti-freeze leak causes excessive levels of water and glycol to be present in engine oil; these levels can be readily detected by FTIR. More frequent monitoring of engine oil by real-time FTIR can quickly catch these contaminants before they have a chance to cause catastrophic damage to an engine.
  • Ascertain the condition of lubricants in remotely deployed equipment, for which the delay in receiving information from off-site labs may be unacceptable… On-site FTIR analysis minimizes the need to send lubrication samples to off-site labs for condition-based monitoring. It is especially important that equipment operating in these remote locations be carefully monitored since ambient conditions may be particularly challenging.
  • Act as the supporting analytical technology in programs designed to bring lubricants back to spec via readditization… FTIR is a powerful method for analysis of anti-wear and anti-oxidation additives. More companies are looking to extend the use of lubricants by refreshing critical additives to bring the lubricant back to spec. Real-time, on-site FTIR can be a powerful tool for determining how much additive should be recharged and for monitoring the overall refreshed oil composition.
  • Enable maintenance personnel to make better decisions on when to send oil samples for full analysis… Real-time FTIR is an excellent screening technology to detect problems with both the lubricating fluid and the lubricated equipment. More frequent screening with FTIR enables personnel to make informed decisions on when to send samples for full elemental analysis, in order to try to pinpoint specific internal machine problems that may indicate excessive mechanical wear. LMT

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July 1, 2008
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LMT News

News of people and events important to the Lubrication Management community

TRICO CORPORATION ACQUIRES PREDICT USA

Trico has purchased Predict USA, of Cleveland, OH, a leading provider of predictive condition monitoring technologies including ferrography, lubricant analysis and vibration analysis. The acquisition will allow Trico to bring oil analysis and monitoring services in house and now offer a one-stop shop for all predictive lubrication management services to its clients. According to Trico’s president Nick Kroll, his company will strengthen the Predict’s ferrography services “Ferrography and the accompanying instrumentation is one of the niche Predict’s strengths,” he notes. “We’re looking to improve this part of the program, along with a host of other services.”

Predict will become a wholly-owned subsidiary of Trico, but continue to operate under its current brand name.

SKF SET TO ACQUIRE PEER BEARING COMPANY

SKF has signed an agreement with the owners of U.S.-based PEER Bearing Company (PEER) to acquire PEER and its manufacturing operations in China and Thailand. Headquartered in Waukegan, IL, PEER primarily manufactures deep groove ball bearings and tapered roller bearings, most of which are sold to North American customers. According to SKF, the acquisition is expected to strengthen the corporation’s presence in certain North American market segments that it doesn’t currently serve, including Mechanical Power Transmission. PEER will continue to operate as a standalone business, acting independently on the market under its existing PEER brand.

The proposed transaction is subject to certain conditions to closing and requires approvals by relevant authorities.

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Bob Asdal, Hydraulic Institute, and Jane Alexander, Editor

Bob Asdal, executive director of the Hydraulic Institute (HI), visits with LUBRICATION MANAGEMENT & TECHNOLOGY editor Jane Alexander, in St. Paul, MN, at the recent Industrial Energy Effi ciency Forum sponsored by Xcel Energy and Pump Systems Matter ™ (PSM). Launched in 2005 by 33 member companies of the Hydraulic Institute, PSM is a national educational initiative that works to help pump users gain competitive advantage through strategic, broad-based energy-management solutions.

The St. Paul forum on May 6 offered multiple presentation tracks focusing on the importance of looking at effi ciency from a systems perspective for Xcel Energy customers across a variety of industries. Incorporating countless real-world examples, the keynote presentations and nine workshops covered a range of issues related to business and reliability strategies, compressed air systems, motors and variable speed drives, life-cycle costing, pump system optimization, mechanical seals optimization, water and wastewater systems and more.

Co-sponsors of the day-long, information-packed event included some of the biggest names in the fi eld of energy-effi cient solutions for industry, including ITT Corporation, Baldor-Dodge-Reliance, Flowserve Corporation, Emerson Motors/US Motors, Emerson Control Techniques-Americas, John Crane International, Sundyne Corporation, AURORA Pump, Armstrong International, Inc. and Sullair Corporation, among others.

For more information on Pump Systems Matter and upcoming educational opportunities for your organization’s energy-effi ciency team, visit www.pumpsystemsmatter.org

ASSOCIATION NEWS: WATER ASSOCIATIONS & EPA RELEASE TOOLS FOR EFFECTIVE UTILITY MANAGEMENT PRACTICES

Six associations representing the U.S. water and wastewater sector, in collaboration with the U.S. Environmental Protection Agency (EPA), have released a series of tools designed to help water and wastewater utilities advance effective management practices to achieve long-term sustainability. The tools are based on the “10 Attributes of Effectively Managed Utilities” and fi ve “Keys to Management Success” fi rst identifi ed in a report released by the group in May 2007. Since the release of that report, the “Findings and Recommendations for a Water Utility Sector Management Strategy,” the Effective Utility Management Collaborating Associations—the American Public Works Association (APWA), American Water Works Association (AWWA), Association of Metropolitan Water Agencies (AMWA), National Association of Clean Water Agencies (NACWA), National Association of Water Companies (NAWC), the Water Environment Federation (WEF)—and EPA have been working together to develop tools aimed at helping utilities assess their current operations and adopt best management strategies for improvement.

“These tools were developed by utility mangers for utility managers,” said WEF executive director Bill Bertera. “The Water Environment Federation is very gratifi ed to have been part of this important effort.” EPA assistant administrator for Water, Ben Grumbles commented that he considers the collaboration among the associations “to be one of the Agency’s most important accomplishments under our Sustainable Water Infrastructure Initiative” and “appreciates the water associations and utility advisors for their continuing leadership.”

The tools now available include the Effective Utility Management Primer for Water and Wastewater Utilities that is designed to help water and wastewater utility managers make practical, systematic changes to achieve excellence in utility performance. It was produced by water and wastewater utility leaders who also developed a series of suggested Utility Performance Measures focused on the Attributes to help utilities establish a performance baseline and begin to measure their progress. Finally, the group is releasing an online Resource Toolbox that contains links to key resources and tools. The new primer can be downloaded at no charge from each of the collaborating associations’ Websites or at www.watereum.org LMT

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July 1, 2008
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Problem Solvers

0708_problemsolvers_img1Viscous Tapping Fluid

Rustlick RTD is a premium tapping fluid for the most demanding reaming, tapping and drilling operations, including jobs with high strength steel, titanium and stainless steel. This thick brown fluid has been formulated with extreme pressure additives that fortify water-based coolants instead of contaminating them like traditional tapping fluids. It significantly reduces friction in operations to give superior cutting performance and finishes as well as prolonging tool life. Rustlick RTD is water soluble and available in a 12-oz. squeeze bottle, as well as 1-, 5- and 50-gal. containers.

ITW ROCOL North America 
Glenview, IL

Lubricant Identification Tags

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Trico’s Spectrum tags and labels help users avoid lubricant cross-contamination and misapplication by identifying lubricants from storage to point of use. Available in 10 colors, the tags are easily marked with up to four lines of information using a felt tip marker, crayon or Spectrum customized label and then sealed beneath a laminate sheet to maintain readability. Optional barcoding also can be added. The tags are made of 1/16″ UV inhibited plastic and designed to withstand harsh environments.

Trico Corporation 
Pewaukee, WI

0708_problemsolvers_img3Bolting Made Easy

Wright Tool’s line of torque multipliers includes three styles: universal tube, plate reaction and foot reaction. These tools range in output capacity from 750 to 8000 foot-pounds. Their compact, rugged, onepiece design is easy to handle and, according to the company, operators rarely need to apply more than 200 foot-pounds of input torque to achieve their output goal. A torque conversion chart is attached to each of these multipliers to show the input torque required for any given torque output.

Wright Tool Company 
Barberton, OH

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Industrial Strength Degreaser

CRC’s T-Force™ Degreaser combines the power of a high-performance, industrial- strength degreaser with lower VOCs. Offering the benefits of Trichloroethylene, Perchloroethylene and n-Propyl Bromide without the associated risks, it quickly dissolves grease, oil and sludge, thus allowing mechanical equipment to operate more efficiently. Available in 20-oz. aerosol cans, the product has a high dielectric strength of 33,300 volts, is non-conductive, noncorrosive, non-staining and has no flash or fire point.

CRC Industries
Warminster, PA

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Drum Cabinets & Accessories

Lyon Workspace Products offers a variety of drum storage cabinets, including configurations that safely house a 55-gallon drum horizontally or vertically, or two 55-gallon drums with space for attached pumps or funnels. Conforming to NFPA Fire Code No. 30 and OSHA standards, each model incorporates a three-point latching system with key lock for secure closure. Lyon also offers drum handling trucks, mobile drum cradles, drum ramps and drum rollers.

Lyon Workspace Products 
Aurora, IL

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Bearing Protection

Electro Static offers two AEGIS SGR Split-Ring Bearing Protection Kits™ (one for NEMA motors and one for IEC motors). They are designed to provide clearance for shaft shoulders, slingers and other end-bell protrusions while keeping bearings safe from electrical damage caused by circulating or shaft currents. Split-Ring Kits are ordered by motor frame size. Standard-size kits fit NEMA-frame motors with shaft diameters from 0.625″ to 3.375″ and IEC-frame motors with shaft diameters from 19mm to 95mm.

Electro Static Technology 
Mechanic Falls, ME

0708_problemsolvers_img7Universally Interchangeable Worm Gearboxes

AutomationDirect has expanded its mechanical power transmission product line to include worm g e a r boxe s in four frame sizes and six gear ratios from 5:1 to 60:1. Constructed of cast iron onepiece housings, the IronHorse™ worm gearboxes feature a C-flange input and carbon steel shaft with either right-hand or dual shaft output and double-lipped embedded oil seals to prevent leakage. Designed to change drive direction by 90 degrees, these products are mountable in any direction, except motor pointing up. The universally interchangeable compact design ensures easy OEM replacement.

AutomationDirect 
Cumming, GA

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