Product category:
Lubricants
News Release from: Kluber Lubrication GB | Subject: Dry lubricants
Edited by the Engineeringtalk Editorial
Team on 18 May 2004
Dry lubricant handles extreme conditions
Kluber has developed a special bearing compound for radial bearings which is very load-resistant and allows lifetime lubrication even with low speeds and very high temperatures.
Dry lubricants can be used for extreme operating conditions They eliminate the risk of oil or grease leakage involved in wet lubrication and make relubrication lines unnecessary
Lifetime lubrication can be attained and running-in behaviour improved.
Because of today's technical progress and legal requirements the trend towards innovative high-performance lubrication looks set to continue.
Higher performance of components normally entails higher operating temperatures causing premature aging of the lubricant.
Conventional total loss lubrication is no longer acceptable.
Depending on the operating conditions, bearing loads and speeds, there are different types of dry lubrication that may be used: bearing compounds which ensure proper lubrication by "chalking off" during operation, bonded coatings or galvanic coatings which incorporate solid lubricants forming a layer between the surfaces in contact.
High requirements have to be met as dry-lubricated bearings too should offer a long service life.
In addition, corrosion protection, resistance to water and chemicals, high speed factors and load bearing capacity are important parameters of dry lubricants.
Dry lubricants are high-performance products suitable for temperatures as high as 280C and as low as -50C.
Also, they show very little gasification under vacuum.
Kluber has developed a special bearing compound for radial bearings which is very load-resistant and allows lifetime lubrication even with low speeds of up to approximately 50,000mm/min and very high temperatures of more than 250C.
This product contains a friction-reducing solid lubricant combination and an inorganic binder.
Eco-friendly application is possible because the product is mixed with water to be filled into the bearings in paste form.
Once the compound has hardened and the bearing rotates freely, small quantities of the compound "chalk off" ensuring continuous dry lubrication.
The rolling movement provides a consistent transfer of dry lubricant to the friction surfaces of the bearing.
The properties of the compound ensure that the chalking quantity is constant within a certain margin.
Excessive chalking would entail risks like bearing jamming, while insufficient chalking would mean increased wear from lubricant starvation.
Dry lubrication offers the following advantages for rolling bearings: "clean" lubrication, no dripping of lubricant, thermal stability up to 550C, no change in consistency or viscosity due to temperature, lifetime lubrication, good corrosion protection, resistance to water and oil as well as easy processing.
On completion of its development, this self-lubricating compound was filled into deep-groove ball bearings as well as spherical roller bearings and subjected to ROF and FE8 rolling bearing tests.
For steel mill applications, eg kilns, the compound was filled into the bearings and tested.
All results are positive and give evidence of reliable lubrication.
Double-row, full complement ball bearings running in kilns were also tested at kiln temperatures of 350-400C for 24 hours per day, 5 days per week.
After an operating period of 1350h both the bearings and the lubricant were still fully fit for use.
The rolling bearing elements and functional surfaces showed minimal wear. Request a free brochure from Kluber Lubrication GB ...
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