Riahi - Department of Mechanical Engineering Iran university of science & Technology, Tehran , Iran
Ansarifard - Department of Mechanical Engineering Iran university of science & Technology, Tehran , Iran

Life cycle assessment for different industrial products has dual advantages. First the economic benefits in determining the real or near real life age of a product and hence, preventing the replacement of that product from pre-matured life cycle. The Second reason is the reduction in the amount of energy being consumed for manufacturing the part in question and as a result, placing a lower impact on the environmental degradation and assisting the conservation of energy in a greater scale. Ball bearing is an important component of any mechanical system comprised of rotating devices. Based on the elimination of friction in providing the rotation where utilized, ball bearings are vastly in use in most if not all technical and industrial applications. In order to bring about relative assurance for appropriate life expectancy in ball bearings and suitable replacement time, diagnosis of parameters having impact on the life of bearings is crucial. To have this matter done properly, a large number of ball bearings could be saved from pre-mature replacement. Design of experiments (DOE) is viewed as one of the more effective tools in achieving breakthrough product improvements and life designs. Most if not all improvements in the higher life expectancy and performance of bearings were derived from a very straightforward and simple form of DOE called two-level factorial design. This investigation was conducted on the basis of previous works conducted on this subject matter along with developing a simple equation to provide a more reliable estimation for ball bearings in use and worn to some extend [1].

Life Estimation, Ball bearing Performance, Metal Surface, Bearing Maintenance