CAT 177-5236 Radial Needle Roller and Cage Assembly

CAT 177-5236 is a Caterpillar single-row radial needle roller and cage assembly, adapted for space-constrained parts such as gearboxes, slewing gearboxes, and hydraulic pump drive shafts in Cat 320/326 excavators, 966K loaders, and D6T bulldozers. It is used for pure radial heavy-duty sliding supports, combining the advantages of high load capacity and compact space adaptation, and is a key component for lightweight and high-density load-bearing in transmission systems. The following is structured technical and application information:

Core Technical Parameters

Item Details
Basic Attributes
Model 177-5236, Type: Single-row radial needle roller cage assembly, Material: Needle rollers are GCr15 bearing steel (quenched HRC62-64), Cage is stamped low-carbon steel (surface phosphated), Single weight approximately 0.42 kg, Applicable temperature: -40℃ to +120℃, Lubrication method: Oil lubrication, Suitable for low-speed heavy-load conditions, limited radial space, only bearing pure radial loads

Key Dimensions
Inner diameter: 63.50 mm (tolerance 0/-0.02 mm), Outer diameter: 82.55 mm (tolerance 0/-0.03 mm), Width: 25.40 mm (tolerance ±0.10 mm), Number of needle rollers: 24, Needle roller diameter: 7.94 mm, Needle roller length: 25.00 mm, Number of cage windows: 24, Window spacing: 15°, Suitable shaft diameter 63.50 mm (tolerance 0/-0.02 mm), housing bore diameter 82.55 mm (tolerance +0.02/-0.01 mm), radial clearance 0.015-0.030 mm
Compatible Models and Applications: Compatible with Cat 320 excavator swing gearbox input shaft, 326 excavator stick cylinder base pin, 966K loader gearbox secondary shaft, and D6T bulldozer balance shaft. One piece per component, installed between the journal and the housing bore, replacing traditional radial bearings and saving installation space. Cat® Parts
Performance Parameters: Rated radial dynamic load ≥95 kN, rated radial static load ≥160 kN, coefficient of friction μ≤0.002 (oil lubrication), limiting speed ≤2000 r/min (oil lubrication), wear life ≥2500 hours (under rated load), impact resistance ≥80 kN (instantaneous radial), needle roller hardness HRC62-64, hardened layer depth 0.8-1.2 mm Structural and Performance Advantages

High Load Capacity: The slender needle roller structure (length-to-diameter ratio approximately 3.15) provides a large contact area within a compact space, with a radial load capacity nearly 1.5 times that of cylindrical roller bearings of the same size. Suitable for heavy-duty and space-constrained applications such as gearboxes and hydraulic pumps.

Low Friction and High Efficiency: The cage precisely separates the needle rollers, preventing roller contact friction. Combined with oil lubrication, the coefficient of friction is as low as 0.002, reducing energy consumption and operating temperature rise, making it suitable for stable transmission under low-speed, heavy-load conditions.

Precise Dimensional Fit: Strict control of inner diameter, outer diameter, and width tolerances creates a clearance fit (0.015-0.030 mm) with the journal and housing bore. No adjustment is required after installation, providing stable support and ensuring transmission accuracy.

Flexible Installation: The absence of inner and outer rings allows for direct assembly between the shaft and housing. Adaptable to various housing structures, it can be cold-pressed or hot-fitted, resulting in high installation efficiency and facilitating rapid on-site maintenance and replacement.

Installation and Maintenance Points:
**Before installation, clean the components, journals, and housing bores. Check for broken needle rollers, deformed cages, and damaged windows.** Use a cold-pressing method (pressure ≤35 kN) with a special pressure block to press the component into the housing bore, ensuring the coaxiality of the needle rollers and journal is ≤0.02 mm. After installation, check the radial clearance to be 0.015-0.030 mm, ensuring smooth rotation without jamming or abnormal noise.

Every 1800 hours of maintenance: Check needle roller wear (replace if needle roller diameter wear ≥0.1 mm or surface pitting), add SAE 15W-40 lubricating oil, and check the wear of the journal and housing bore. If journal wear ≥0.05 mm, replace the component simultaneously to prevent premature component failure.

Prioritize original equipment manufacturer (OEM) parts. Aftermarket parts may have insufficient needle roller material purity, inadequate cage strength, or dimensional deviations, which can easily lead to needle roller breakage, cage deformation, shaft jamming, and affect equipment operating safety.