Ways to improve the stability of linear guides
1. Accuracy level:
Generally, the accuracy of linear slides is divided into five types: ordinary, advanced, precision, ultra-precision and ultra-high precision.
2. There are generally three main detection indicators.
1. It is the parallelism between the slider C and the surface A of the slide rail,
2. It is the parallelism between the slider D and the B surface of the slide rail,
3. It is the parallelism of walking. The so-called parallelism of walking refers to the error of parallelism between the guide rail and the reference plane of the slider when the linear slide rail is fixed on the plane of the reference seat so that the slider moves along the stroke. Different accuracy levels correspond to the running parallelism error of the slide rail.
3. The life span of linear slides is relatively large. In order to facilitate the selection of linear guide pairs, the following important concepts must be clear.
a. Rated life: The so-called rated life refers to the running distance of a batch of the same products under the same conditions and rated load, 90% of which have not had surface peeling phenomenon.
b. Basic dynamic load rating (C): The so-called basic dynamic load rating refers to a batch of linear guide pairs of the same specification. In the state of equal load direction and size, after running for 50km, 90% of the linear slide rails will roll The highest load when the road surface does not produce fatigue damage (peeling or pitting). The linear guide pair uses steel balls as the rated life of the rolling elements, which is 50km under the basic dynamic rated load.
c. Basic static load rating (Co): The so-called basic static load rating refers to the total permanent deformation of the steel ball and the surface of the raceway at the contact surface subject to the maximum stress under the state of equal load direction and size. Static load of one ten thousandth hour.
It is worth mentioning that the linear guide pair with two rows of Goethe-style structure can withstand forces and moments in all directions. It is used in light load or medium load applications, especially when the lateral force load is large. However, the four-row arc-type linear guide rail is often used in heavy or over-load applications, and the arc type has the ability to absorb the error of the assembly surface. However, if there is an impact load, the linear guide pair of Goethe-type structure should be used. As far as users are concerned, the product is applicability and reliability. Both the Goethe-type structure and the arc-type structure have their applicable application environments.
As the precision requirements in mechanical processing are getting higher and higher, the precision grades of the linear slides of important components on the processing machinery are getting finer and finer. For the precision grade classification and guide rails, the precision grades are from ordinary grade to Advanced, precision, high-precision, ultra-precision and ultra-high-precision levels, etc., he is fully capable of these.
In the process of guide rail selection, you can return to the previous step at any time according to the calculation result to reselect and set. When calculating the maximum load of the slider, it is necessary to confirm that the static safety factor of the linear slide rail selected should exceed the value listed in the recommended table. If the selected linear guide pair has insufficient rigidity, you can increase the preload, increase the selection size or increase the number of sliders to increase the rigidity. The static safety factor is defined as the ratio of static rated load to working load.