Load Rating and Life of Linear Chain Guides

Linear chain guide life is the rolling body or rolling surface because of the role of cyclic stress, to the appearance of the rolling material due to the appearance of the metal spalling occurred in the rolling commission of the total distance run.

　　(1)Basic rated static load

　　Linear chain guide in the static or low-speed operation of the load is too large or impact, between the rolling body and rolling surface will produce local permanent deformation, this permanent deformation if more than a certain limit, it will affect the smoothness of linear chain guide activities.

　　The so-called basic rated static load keyword ranking, is to produce zui big stress at the contact surface, so that the rolling body and rolling surface between the sum of the permanent deformation of the rolling body diameter of 0.000.times, the direction and size of the static load. So the basic rated static load is the limit of the permissible static load.

　　(2)Allowable static moment

　　In the linear chain guide on the role of the moment, from the PMI linear chain guide within the rolling body stress distribution, the two ends of the rolling body to produce zui big stress. So the allowable static moment is the limit of the static moment.

　　(3) Static safety factor

　　When the linear chain guide used in vibration, impact or intense start to stop the situation, because of inertia or moment and other external forces, there will be a large load, for such a load state, there is a need to consider the static safety factor.

　　(4) Basic dynamic load rating

　　Even if a unified batch of products manufactured under the same conditions, the life of the linear chain guide will be slightly different. Therefore, in order to determine the life of the linear chain guide, the rated life as defined below is used as usual. The so-called rated life is a batch of linear chain guide with the same specifications in the same conditions of activity, of which 90% does not produce the appearance of the signs of depreciation and peeling of the overall distance that can be travelled. When the linear chain guide is subjected to load and activity, the basic rated dynamic load is used to calculate its life.

　　The so-called basic rated dynamic load is a group of the same specifications of the linear chain guide in the same conditions of activity, when its rolling body for the ball, its rated life of 50km, and its rolling body for the roller, the rated life of 100km, the direction and size of the load are unchanged.

　　(5)Calculation of life

　　The rated life of a linear chain guide is different because of the load it is subjected to in reality, and the service life can be deduced from the basic rated dynamic load and working load in accordance with the selected specifications. The service life of linear chain guide will be changed with the activity condition, hardness of rolling surface and ambient temperature.