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Munich, Germany

Zuleeg J.,Kluber Lubrication
Society of Tribologists and Lubrication Engineers Annual Meeting and Exhibition 2014 | Year: 2014

This article provides a rough overview of the rolling bearing testers normally used in the industry. As these methods are highly varied, this project was focused on developing a software which not only enables a standardised method to be used with all these testing machines, but can also generate additional information from the results, e.g. how often an individual particle is rolled over. To obtain results going beyond the greased bearing's noise behaviour during first few seconds or minutes of running, a test method was developed to determine the noise behaviour throughout the grease life. Lubricants performing very well in the standard noise test may show much poorer results in the lifetime noise test. It is therefore highly advisable to bear long-term noise generation in mind when developing a low-noise grease. Source


Zuleeg J.,Kluber Lubrication
SAE Technical Papers | Year: 2015

Tribological contacts between plastic or polymer materials can exhibit stick-slip behaviour that generates noise. Tribological properties can be influenced by lubricants such as bonded coatings, greases, and fluids. In this paper, well known theories about polymer friction from the literature will be shown to be useful in the development of new lubricants. Theoretical results have been validated with a Ziegler Stick-Slip Test Rig. The test methods presented in this paper are used in the development of lubricants for automotive applications (in the interior of the car including invisible lubricants developed for Class "A" surfaces). Copyright © 2015 SAE International. Source


Hochmann M.,Kluber Lubrication
American Gear Manufacturers Association Fall Technical Meeting 2012, AGMA | Year: 2012

To find out if the high-performance gear oils of today are able to reliably protect gears and rolling bearings in gearboxes against damage also at a reduced oil temperature of 40 °C, different high-performance gear oils were examined on a FZG back-to-back gear test rig as well as on a FE8 bearing test rig by modifying the standardized test methods. It has been shown that the advanced additive technologies used in today's high-performance gear oils are capable of inducing the required reactions on the surfaces of gears and bearings also at 40 °C, thus providing reliable damage protection even under these operating conditions. Source


Recker C.,Kluber Lubrication
Tribologie und Schmierungstechnik | Year: 2011

A discussion covers the composition, effectiveness, and most important features of lubricating oils for plain bearings with an emphasis on the properties and performance of special lubricants for plain bearings. Discussion topics include introduction; types of lubricants for plain bearings; composition of lubricating oil (mineral oils; synthesis oils; synthetic hydrocarbon oils, polyalphaolefins (PAO); ester oils; polyglycols; silicone oils; perfluorinated polyether oils (PFPE)); chemical and physical characteristics of lubricating oils, viscosity; composition of lubricating greases; types of thickeners; soap thickeners (metal soaps, lithium complex soaps, aluminum complex soaps, calcium, barium complex soaps, sodium complex soaps); non-soap thickeners (bentonite, polyurea, PTFE); chemical and physical characteristics of lubricating greases, and miscibility and compatibility of lubricating oils and greases. Lubricants are used as a function of the conditions of use, such as speed, load, and temperature. Operation with low wear in mixed friction conditions, low friction moments at high speeds, good startup behavior with frequent starts and stops, and so on require the proper lubricant in plain bearings. The correct lubricant for a given use is a component of a structure. Plain bearing lubricants are as various as the uses, types, and materials of plain bearings. They include lubricating oils (hydrodynamic, hydrostatic, and sintered plain bearings) and greases (steel/steel ball and socket bearings, bronze plain bearings under mixed friction), polymeric self lubricating films with solid lubricants (corrosion protection and running in optimization, also lubricating waxes, and lubricating emulsions), and lubricating pastes with solid lubricants such as PTFE, graphite, or molybdenum disulfide. The advantages and disadvantages of use of all the above lubricating systems are cited. Source


A discussion covers re-lubrication and lubrication control of oil lubricated hydrodynamic white metal sliding bearings and of grease lubricated bronze sliding bearings that operate with precedence under mixed friction conditions. Sliding bearings are often lubricated with lubricating oil or lubricating grease although there are a number of maintenance-free and self-lubricating dry running sliding bearings. Discussion topics include introduction; selecting oil or grease as the lubricant; standardized lubricants; lubrication facilities; testing the oil and used oil analysis; cleaning the oil; service life of the lubricant; oil change/used oil disposal; and summary. The continuous supply to sliding bearings of fresh lubricant brings about low friction, maintenance that can be planned, and keeps production downtimes to a minimum. Numerous examples of standardization activities in the country are provided such as of the NAWGL, FAM, NMP, DGMK, Beuth Verlag, DIN, and DIN ISO. Sixteen DIN ISO standards relating to lubricants are cited. Continuous re-lubrication leads to long sliding bearing service life and functioning. A number of systems are on the market. Those to be selected should involve the least maintenance expense, simple retrofitting, and optimal number of sites to be lubricated. All standards can be obtained at Beuth Verlag that exclusively sells standards and VDI guidelines. Copies or representations of the contents are not allowed. The Beuth Verlag is a DIN subsidiary and is responsible for the sale of standards. In its web shop already over 300,000 documents are findable of which over half can be downloaded. Over 80,000 customers use this service that has been available for 9 yr. The discussion section on oil testing and used oil analysis includes viscometry, IR spectroscopy, elemental analysis, Karl Fischer water analysis, neutralization number, and methods for particle determination. Numerous observations are made. Source

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