CAT 581-9015 BEARING-SELF-GD

CAT 581-9015 (YM Quality) is a Caterpillar articulated chassis self-aligning ball bearing, suitable for articulated steering knuckles of loaders, graders, and other equipment. It can automatically compensate for installation and working condition misalignment, withstand medium to high radial loads, and reduce vibration and wear. YM represents a high-quality replacement part with performance consistent with the original manufacturer and strong compatibility with Cat®… The following are the core information and key points:

Core Technical Parameters

Item Details
Part Model CAT 581-9015 (5819015) Self-aligning ball bearing, used in articulated chassis steering knuckles to compensate for angular deviations and ensure smooth steering

Material Inner/outer rings are chromium bearing steel (GCr15), balls are silicon nitride ceramic/chromium steel, cage is reinforced nylon 66, seal is nitrile rubber (NBR), grease is lithium-based grease (NLGI 2), temperature resistance -40℃ to 120℃

Key Dimensions Inner diameter 50mm, outer diameter 80mm, width 23mm, ball diameter 12.7mm, contact angle 15°, clearance class C3, compatible pin diameter 50.01-50.03mm, mounting hole diameter 80H7, installation tolerance ±0.02mm

Compatible Models CAT 938K/950H This product is suitable for articulated chassis of loaders, 140M graders, D6K bulldozers, etc., for use in the front/rear frame articulated steering knuckles. It uses 425-3581 pins and 425-3580 seals, and is suitable for steering pressures up to 10MPa.

Performance Parameters: Radial rated load 25.5kN, limiting speed 3600rpm, operating temperature -40℃ to 120℃, angle compensation range ±2°, friction coefficient ≤0.0015, lubrication cycle 500 working hours.

Core Functions and Structural Features:

Automatic Angle Compensation: The outer ring spherical raceway design allows for ±2° angular deviation, compensating for frame deformation, installation errors, and steering misalignment, avoiding edge loads, reducing bearing and pin wear, and extending component life (Cat®…).

Medium-High Radial Load Capacity: The combination of chrome steel material and ceramic/chrome steel balls adapts to the radial load during articulated steering, withstands impact vibrations, ensures steering stability, and reduces steering resistance and energy consumption.

Low Friction and Sealing: A reinforced nylon cage reduces friction, NBR seals prevent dust and mud intrusion, and lithium-based grease provides long-lasting lubrication, making it suitable for harsh outdoor conditions and requiring extended maintenance.

Easy Installation: Standard size fits the original mounting base; cold press installation is sufficient, requiring no additional adjustments. YM quality parts have the same dimensional accuracy as the original, ensuring smooth steering without jamming or abnormal noise after installation.

Installation and Maintenance Points:
Installation Specifications: Clean the bearing, pin, and mounting base, removing impurities. Check the bearing for cracks and ensure the seals are intact. Use a pressing tool to smoothly press the bearing into the mounting base, ensuring the bearing end face is flush with the base surface without misalignment.

Install the pin and test steering flexibility; ensure there is no jamming. Replenish with lithium-based grease (NLGI 2) every 500 working hours to ensure adequate lubrication.

Maintenance Recommendations: Check every 1000 working hours: bearing clearance, steering noise, and seal aging. Replace immediately if increased clearance (>0.2mm) or abnormal noise is detected to prevent loss of steering control.

When replacing bearings, replace the pins and seals simultaneously to prevent uneven wear from causing rapid damage to the new bearings and to ensure the long-term stability of the articulated steering system.