CAT 191-2685 Bearing – Needle(Debris Resistant)

CAT 191-2685 is a Caterpillar original single-row radial needle roller cage roller assembly (without inner and outer rings, the shaft and housing directly serve as the raceway). It is compatible with the planetary gear trains, idler shafts, or connecting rod articulation points of the 793D mining truck and D11T bulldozer, used to withstand heavy radial loads under extreme operating conditions. The following is a professional technical and application guide:

Core Technical Parameters (Professional Version)

Item Details Basic Attributes Model 191-2685, Type Single-row radial needle roller cage roller assembly (including stamped steel cage + full complement needle rollers, without inner and outer rings), Compatible with Cat 793D mining truck gearbox planetary gear sets, D11T bulldozer drive axle idler shafts, 992K loader boom connecting rod articulation shafts, and 785D mining truck balance shaft bearing housings. Material is needle rollers (SAE 52100 bearing steel, hardened to HRC 62-66, diameter…) 4.762 mm diameter, cage (SAE 1010 steel sheet stamping, galvanized and passivated surface), inner diameter 65.0 mm (tolerance JS6, +0.018/-0.018 mm), outer diameter 75.0 mm (tolerance h7, 0/-0.030 mm), width 28.0 mm (tolerance ±0.20 mm), unit weight approximately 0.95 kg, rated radial load Cr≥180 kN, rated static load Cor≥220 kN, operating temperature -40℃ to +120℃, lubrication method is grease lubrication (NLGI 2 lithium-based grease) / oil lubrication (ISO VG 68 anti-wear hydraulic oil), limiting speed (grease lubrication) ≤3200 rpm, (oil lubrication) ≤4000 rpm. Key dimensions: Number of needle rollers: 32 (diameter 4.762 mm × length 28.0 mm, chamfered ends 0.5). (mm×45°), cage window clearance 0.2-0.4 mm, total needle roller length 28.0 mm (tolerance ±0.15 mm), inner diameter fits shaft diameter 65.0 mm (journal surface hardness HRC 58-62, roughness Ra≤0.4 μm), outer diameter fits housing bore diameter 75.0 mm (housing bore surface hardness HRC 56-60, roughness Ra≤0.6 μm), radial clearance 0.04-0.08 mm (determined by shaft and housing tolerances).

Material and Manufacturing Process: Needle rollers are vacuum quenched + low-temperature tempered, and the surface is ultra-precision ground (Ra≤0.2 μm). The cage adopts an integrated stamping and riveting structure, eliminating the risk of loosening or deformation. Needle roller contact fatigue life ≥5000 hours (under rated load), impact load resistance ≥30 kN, and repeatability ≤0.10 mm.

Compatible Models: Cat 793D/785D This product is used in mining truck gearbox planetary gear sets, D11T/D10T bulldozer drive axle idler shafts, 992K/988H loader boom connecting rod hinge shafts, and 789D mining truck steering knuckle vertical shafts. Its core function is to provide heavy-duty equipment with raceway-less bearings without inner or outer rings. It is suitable for radial loads ≥150 kN and speeds ≤3000 rpm, replacing traditional bearings with inner and outer rings to reduce radial installation space and ensure transmission/support accuracy. Assembly fit: It has a clearance fit with the shaft (0.02-0.05 mm for easy installation and positioning) and a clearance fit with the housing bore (0.03-0.06 mm). After installation, axial positioning uses retaining rings (e.g., 7I-4696) or shoulders. Radial runout ≤0.08 mm, axial movement ≤0.10 mm, and coaxiality error with the matching sleeve (e.g., 498-5587) ≤0.05 mm. Installation and Maintenance Points: Before installation, clean the needle roller assembly, journal, and housing bore. Check that the needle rollers are free of rust, the cage is free of deformation, and the journal and housing bore surfaces are free of scratches and burrs. Measure the shaft diameter/bore diameter and roundness to ensure they meet tolerances (journal roundness ≤ 0.02 mm, housing bore roundness ≤ 0.03 mm).

During assembly, smoothly place the assembly into the housing bore. Use a special tooling guide to guide the shaft fitting, ensuring the needle rollers fit evenly and without jamming. After installation, use a retaining ring or shaft shoulder to axially lock and prevent axial movement.

Maintenance Recommendations: Check the lubrication status and needle roller wear every 800 hours. If pitting or peeling appears on the needle roller surface, or if the wear on the journal/housing bore is > 0.10 mm, immediately replace the assembly and repair the journal/housing bore to prevent decreased transmission accuracy or assembly jamming.