The rigidity of a linear system must be taken into consideration when it is to be used in high-precision positioning devices or high-precision machinery. Preloaded slide guides and ball splines, which use balls as the rolling elements, are available upon request to meet the need for greater rigidity. If a force is applied to the ball elements without preload, an elastic deformation proportional to the applied force to the 2/3 power will result.
Preload is categorized into three ranges: standard, light, and medium for option. In the NB linear system, preload is applied by installing rolling elements that are slightly larger than the standard. Therefore, the specification of the preload is expressed by a negative value.