How to choose the preloading level of ball spline?

The preloading of ball splines has a significant impact on accuracy, load resistance, and rigidity, so it is necessary to select the appropriate clearance (preloading) according to the intended use. The gap values of each model have been standardized, so they can be appropriately selected according to the usage conditions.
Rotation direction clearance
In the ball spline, the total circumferential clearance is taken as the rotational clearance and standardized.
Preloading and rigidity
Preload is a load applied to the ball bearings in advance with the aim of eliminating clearance in the direction of rotation and improving rigidity. When preloading is applied, the ball spline can eliminate the rotational clearance and increase rigidity according to the strength of preloading. Compared with no preloading, the displacement at the same torque is half, and the rigidity is more than twice.
Selection of usage conditions and preloading
The selection direction clearance of ball spline has a significant impact on the accuracy or rigidity of the spline outer cylinder. Therefore, it is important to select appropriate gaps based on their intended use. Generally speaking, products with preloading are used. When performing repeated selection movements or reciprocating linear movements, there will be a lot of vibration impact, so applying preloading can significantly improve the lifespan and accuracy.
Selection criteria for direction clearance of ball spline
Zero preload P0: The usage conditions are:; Where you want to drive smoothly with small force, torque always acts in a certain direction. Select key points; Various measuring devices, automatic gun roundness machines, power meters, winding machines, automatic welding machines, automatic packaging machines, shape measuring devices, etc.
Light preloading P1: usage conditions; Select key points for places that are subjected to cantilever loads or torque, require high precision repetition, and have alternating loads; Industrial robots' rocker arms, various automatic loading and unloading machinery, automatic painting guide shafts, EDM machine spindles, stamping die guide shafts, drilling machine spindles, etc.
Medium preloading P2: usage conditions; Select key points for areas that require high rigidity and are prone to vibration and impact, where one spline outer cylinder is subjected to torque; Construct the steering axis, welding axis, and automatic disc tool table indexing axis for vehicles.