I. Bearing Type LFR series U-groove guide rollers (Gothic arch groove, double-row angular contact ball rollers)—commonly known in the industry as U-groove rollers or linear guide rollers—are designed to fit onto round shaft rails for rolling guidance. The outer ring features a central U-shaped arc groove that makes two-point contact with the cylindrical rail (at a 60° angle), providing self-centering capabilities and resistance to off-center loads. Internally, they utilize a double-row angular contact ball structure with a thickened outer ring, offering superior load-bearing capacity and high-speed performance compared to standard deep-groove ball bearings. These are non-separable, integrated rollers designed for direct shaft mounting (no integral stud/bolt).
KDD: Seal suffix = Double-sided stamped metal dust shields (ZZ metal seals);
NPP (alternative in the same series): Double-sided rubber seals (2RS; offers superior dust and water resistance).
II. Standard Dimensions (mm) Inner diameter (d): 12 Outer diameter (D): 35 Total width (B/C): 15.9 Compatible shaft diameter (ds): 12 Total mounting height (AT): 20.65 Minimum chamfer (r): 0.6 Weight: Approx. 0.068 kg
III. Load Parameters Dynamic load rating (Cr): 8300 N (8.3 kN) Static load rating (Cor): 5000 N (5.0 kN)
IV. Material and Characteristics Material: GCr15 bearing steel; through-hardened and precision-ground. KDD Metal Seals: Suitable for dry, low-dust, and high-speed operating conditions; offers good heat dissipation. Advantages: High speed, low noise, self-centering, wear resistance, and ability to withstand radial loads from both directions. Comparison with NPP Rubber Seals: KDD offers higher limiting speeds, while NPP provides superior dust and water protection.
V. Typical Applications Automated assembly lines, packaging machinery, textile machines, woodworking engraving machines, door guide rails, conveyor equipment, and small linear motion mechanisms; designed for use with Φ12mm solid round guide rails.
