MRO Magazine

SKF Life Theory adopted as the new DIN ISO Standard for bearing life calculations

Gothenburg, Sweden -- The International Standards Organization (ISO) has adopted the SKF Life Theory in ISO 281. T...


July 18, 2006
By MRO Magazine

Gothenburg, Sweden — The International Standards Organization (ISO) has adopted the SKF Life Theory in ISO 281. This follows the adoption of the SKF Life Theory in Germany by DIN as DIN ISO 281, Beiblatt 1 & 4, in 2004.

This decision comes after six years consideration and validation by various ISO committees. The final draft was voted-in in March 2006 and the new ISO formula is to be issued in July 2006.

SKF’s Life Theory was developed during the 1980’s by Prof. E Ioannides and T Harris, and has been revised during the years as a result of more knowledge, testing and research at SKF. The theory introduced for the first time the presence of a fatigue limit as a major factor affecting bearing life. Further work recognized in quantifiable terms the detrimental effects of lubrication and contamination on bearing life.

The new ISO Standard is expressed as a new formula that takes into account the effects of a fatigue limit, lubrication and contamination according to the principles laid out in the SKF Life Theory and subsequent SKF publications.


The first ISO Standard for bearing Life, issued in 1962, also adopted the SKF formulas and calculation for life theory at that time. The work was performed by SKF’s Arvid Palmgren and Professor Gustaf Lundberg of Chalmers University Sweden.

Commenting on the news, SKF’s CEO Tom Johnstone said “SKF has once again set the standard in the bearing industry, after almost 100 years in operation. It is true testament to our vision and practice of being a Knowledge Engineering Company. The new ISO 281 Standard demonstrates quite clearly that SKF is undoubtedly the bearing technology and knowledge leader.”

SKF is a leading global supplier of bearing and elastomeric products, solutions and related services, as well as linear motion and lubrication technologies. Headquartered in Gothenburg, Sweden, with technology centres in the Netherlands, Italy and the United States, SKF is a partner to original equipment manufacturers and a major supplier to the automotive, aerospace, heavy-duty/off-highway, marine and other industries.