Design Recommendations for the use of DryLin R

Various recommendations should be observed for the successful use of DryLin R maintenance-free linear bearings.

Eccentric forces
A linear guide cannot always be designed in such a way that the load and the driving forces are arranged in the center between or above/below the guide.
The bearing spacing and the distance between the guide shaft and the load (drive or mass) should not exceed a certain ratio, due to the relatively high friction of DryLin linear bearings. This ratio is limited to approximately 2:1 for linear bearings in dry applications, i.e. the maximum permitted distance between the guide and the force is double the distance between the two bearings. For example, if the distance between the guide and the force is 8 inches, then the distance between the two bearings on the same shaft must be at least 4 inches.

Configuration in the case of supported shafts
When using supported shafts, the maximum load may have to be reduced, depending on the installation conditions.
While 100% of the maximum load is possible with horizontally mounted shafts, the bearing load capacity drops to 35% in the case of suspended arrangements.

Avoiding edge pressure in the case of shaft deflection
The slightly larger bearing clearances of DryLin R linear bearings are usually sufficient to avoid shaft jams in the event of shaft deflection. The use of self-aligning adapters is recommended for larger bearing spacings, as these are able to adjust individually to the deflection.

Avoiding jamming effects in parallel shaft configurations
If the misalignment between two parallel shafts is too large, the bearing can jam. This can be avoided by careful alignment of the shafts. Another possibility is to make either a guide shaft or a bearing unit self-aligning. Self aligning DryLin R designs are available. The DryLin R range provides special pillow designs for this purpose.


Self-Aligning Feature
The range of DryLin R self-aligning bearings offers two great benefits: Automatic adjustment for total load and compensation of alignment errors and potential binding problems. A raised spherical area on the OD of the aluminum adapter allows the bearing to move in the pillow block. Reductions in load-bearing capacity are avoided as the shaft is always supported on the entire projected surface area. Edge pressure is avoided. O-Rings are standard on all self-aligning DryLin R bearings. The self-aligning feature is offered on standard, open and split-housing designs.