CAT 586-6812 BEARING-CUP-GD

CAT 586-6812 GD is a Caterpillar original single-row tapered roller bearing outer ring (GD indicates geometric dimension/tolerance accuracy grade). It is suitable for the final drive, differential, or gearbox shafts of mini excavators and loaders. It works with the inner ring and roller assembly to withstand radial and bidirectional axial combined loads, ensuring shaft positioning and stable operation in heavy-duty transmission systems. It is suitable for low-to-medium speed, high-impact power transmission scenarios in construction machinery.

Core Technical Parameters

Item Details
Part Model: CAT 586-6812 GD (5866812 GD) Tapered Roller Bearing Outer Ring, original factory part number, GD grade precision (radial runout ≤0.005mm, axial runout ≤0.008mm), requires matching with the same model inner ring + roller assembly.

Material: Bearing steel SAE 52100, integrally quenched HRC 60-64, surface ground + ultra-precision ground, roughness Ra≤0.2μm, suitable for gear oil (ISO VG 80-140) lubrication, operating temperature -30℃ to 120℃

Key Dimensions: Inner diameter 90mm (taper 1:12), outer diameter 120mm, width 25mm, outer ring raceway contact angle 15°, seat bore tolerance H7, inner ring clearance 0.012-0.018mm, static interference. 0.01-0.02mm
Compatible Models: CAT 305.5E2/306E2 excavators, 906M/907M loaders, 247B skid steer loaders. Used for final drive planetary carrier support, differential half-shaft bearing outer ring, and gearbox second shaft rear bearing housing.
Performance Parameters: Rated radial load 45kN, axial load 18kN, limiting speed 4000r/min (oil lubrication), can absorb transmission system impact load ≤80kN, compatible shaft runout ≤0.02mm.
Core Functions and Structure:
Combined load bearing: Tapered roller line contact + conical surface design, can simultaneously withstand radial loads and bidirectional axial loads, suitable for final drives, differentials, and other parts subjected to both radial and axial forces, ensuring gear meshing accuracy and transmission efficiency.

Separable Assembly: The outer and inner rings are separable, facilitating installation and removal in confined spaces (such as the final drive housing). Maintenance eliminates the need for complete shaft disassembly, reducing labor costs. Simultaneously, the raceway precisely guides the rollers, minimizing friction and noise.

Shaft Positioning and Buffering: In conjunction with the inner ring and cage, it provides radial and axial positioning of the shaft, suppressing shaft movement and vibration, absorbing impact loads from frequent start-stop cycles, and extending the service life of the shaft, gears, and bearing assemblies.

Installation and Maintenance Points:
Installation Specifications: Clean the seat bore and outer ring, removing oil and metal shavings. Check that the seat bore roundness is ≤0.01mm and the surface is free of scratches/rust. Press in cold (using a special pressure block applied to the outer ring end face). Do not strike the raceway. After installation, check the fit between the end face and the seat bore step (gap ≤0.01mm). Install the bearing with the same model inner ring and roller assembly, adjust the preload (axial clearance 0.005-0.01mm) to ensure smooth bearing operation, and confirm that the lubrication channels are clear before adding gear oil for pre-lubrication.

Maintenance Recommendations: Every 1000 working hours, check: gear oil level/quality (no metal debris, no emulsification), bearing temperature ≤85℃; if grinding debris from the outer ring raceway is found in the oil, replace the outer ring and matching components immediately.

During overhauls, simultaneously check the seat bore wear (wear exceeding 0.03mm requires seat bore repair). Replacement must be done as a set with the inner ring and roller assembly to avoid premature assembly failure due to wear of a single component.