The life of the linear guide

1..Rated Life
The life of the linear guide has great dispersion, even if the products manufactured in the same batch are used in the same motion state, the life will be different; this is mostly due to the inherent changes in the fatigue characteristics of the material itself. Therefore, in order to define the life of the linear guide, the rated life is generally used as the benchmark; the definition is: a batch of the same products, operating under the same conditions and rated load one by one, of which 90% of the total can be achieved without surface peeling. running distance.

2Life
When the linear guide is under load and moves, the surface of the ball track and the steel ball are continuously subjected to the action of cyclic stress. However, when the critical value of rolling fatigue is reached, the contact surface will start to produce fatigue damage, and the peeling phenomenon of fish-scale flakes will occur on part of the surface. This phenomenon is called surface peeling. The definition of life is the total running distance until the surface of the ball track and the steel ball are peeled off due to material fatigue.

3. Calculation of lifespan
The service life of the linear guide will vary depending on the actual working load. The service life can be calculated by selecting the basic dynamic load rating and working load of the linear guide.
4. Life coefficient
(1) Hardness coefficient (fh)
The hardness of the contact surface of the ball track of the linear guide is required to be HRC58 at a certain hardened high level -62, if the hardness value cannot reach the required level, the rated load and service life of the linear guide will be reduced. At this time, the dynamic and static rated loads are the values ​​listed in the dimension table and multiplied by the corresponding hardness coefficient.
The hardness of the linear guide rails used by HIWIN are all above HRC58, so fh is 1
(2) Temperature coefficient (ft)
The system temperature will affect the linear guide The material has an influence. When the temperature is higher than 100°C, the rated load and service life of the linear guide will be reduced. At this time, the dynamic and static rated loads are the values ​​listed in the dimension table and multiplied by the corresponding temperature coefficient. Since some accessories are made of plastic material and are not resistant to high temperature, it is recommended that the operating temperature should be lower than 100°C.
(3) Load factor (fw)
The load acting on the linear guide rail includes the self-weight of the device itself, the inertial load when starting and stopping and the moment load caused by the suspension, as well as the vibration and impact load accompanying the movement. The load is not easy to calculate. According to experience, according to the load condition and the speed of use, it is recommended to multiply the calculated load value by the corresponding load factor.