CAT 123-8912 Bearing-Caged Roller Assembly

CAT 123-8912 is a Caterpillar locking needle roller bearing assembly, adapted for positioning and locking mechanisms in transmission systems such as gearboxes and transfer cases. It is used to withstand radial loads and achieve precise shaft locking. The following is structured technical information.

Core Parameters (Professional Version)

Project Details
Basic Attributes Model 123-8912, Locking Needle Roller Bearing Assembly, 1–2 pieces per unit, compatible with gearbox/transfer case positioning and locking mechanisms, with built-in cage and locking clip, shaft and housing as inner and outer rings, used for radial load support + shaft locking, anti-loosening design

Key Dimensions Compatible shaft diameter 25 mm, compatible housing inner diameter 35 mm, roller outer diameter 32 mm, length 28 mm, needle roller diameter 3 mm, quantity 22, locking clip thickness 2 mm, total assembly clearance 0.015–0.03 mm

Material and Process The cage is SPCC cold-rolled steel, the needle rollers are SUJ2 bearing steel, surface carburized and quenched HRC60–64, the locking clip is 65Mn spring steel, the cage pocket accuracy is H6, the needle roller cylindricity ≤0.002 mm

Performance Parameters Radial rated dynamic load ≈ 8.5 Radial rated static load ≈ 18 kN, limiting speed ≤ 2800 rpm, locking force ≥ 5 kN, operating temperature -40℃ to +120℃, axial load ≤ 1 kN. Compatible with Cat 950/962 loaders and 320 excavator gearboxes; compatible shaft systems such as 123-8911 and 123-8913; can replace older locking bearing assemblies of the same specifications.

Installation and Maintenance Points: Clean the shaft and housing before installation, ensuring no burrs or rust. Shaft surface hardness ≥ HRC58, surface roughness Ra ≤ 0.8 μm, and housing bore roundness ≤ 0.01 mm.

Cold press assembly: Use a special tooling to evenly press the assembly in, ensuring the needle rollers fit snugly against the shaft/housing. Secure the locking clips into the shaft groove to prevent jamming due to uneven load.

After assembly, radial runout should be ≤0.03 mm. Fill with Cat 106-9900 grease (1/3–1/2 of the bearing cavity volume) and check the elasticity and tightness of the locking clips.

Every 1200 hours, check for cage deformation, needle roller wear, and the integrity of the locking clips. Replace any abnormalities immediately to prevent shaft locking failure.