Bk Needle Roller Bearings Bk2216 Bk5020 Bk5520 Bk6020 Bk0912 Bk1012 Bk2520 Bk2820 Bk3020 Bk3520 Bk4020 Bk4520

UJK BK Series Drawn Cup Needle Roller Bearings: English Introduction

The UJK BK Series comprises precision-engineered drawn cup needle roller bearings with a closed-end design, offering exceptional radial load capacity in minimal radial space. These bearings feature a thin-walled, deep-drawn steel outer cup that eliminates the need for an inner ring-instead, the hardened shaft surface serves as the inner raceway. This construction reduces the radial cross-section by 15-30% compared to conventional bearings, making them ideal for space-constrained applications like automotive transmissions, gear pumps, and power tools258.

Key Features & Benefits:

1. Closed-End Design:

   • The sealed base (closed end) prevents lubricant leakage and shields against contaminants, enabling use in exposed shaft-end applications. Synthetic rubber seals (optional suffix: RS/2RS) extend service life in dusty or humid environments, with operational temperatures ranging from -20°C to 120°C210.

   • Supports minor axial guidance forces, enhancing stability in dynamic assemblies5.

2. High Load Capacity & Rigidity:

   • Engineered with a full complement of needle rollers (diameter ≤5 mm, length-to-diameter ratio ≥2.5) and a reinforced cage (steel stamping or nylon options). This design delivers up to 28 kN dynamic load capacity (e.g., BK3020) despite the compact profile4810.

3. Simplified Installation & Cost Efficiency:

   • The drawn cup enables press-fit installation into housings without additional axial fixation. Pre-lubricated with lithium-based grease, reducing maintenance needs26.

   • Eliminates inner ring costs, offering a cost-effective solution for high-volume industrial applications8.

4. Material & Durability:

   • Outer Cup: Carburized low-carbon steel (e.g., ST14/DC01), hardened to HRC 58-64 for wear resistance28.

   • Needle Rollers: GCr15 bearing steel, precision-ground to G2 tolerance (±2 μm diameter accuracy)810.

Typical Applications:

• Automotive: Axle joints, transmission systems, steering columns27.

• Industrial Machinery: Gear pumps, compressors, textile equipment9.

• Consumer Products: Power tools, electric scooters, household appliances (e.g., mop mechanisms)2.

Dimensional Table: UJK BK Series Needle Roller Bearings