CAT 281-2922 RETAINER

CAT 281-2922 is a Caterpillar shaft retainer (circlip/retaining ring) for engine rocker arm shafts, hydraulic pump drive shafts, or gearbox output shafts. Its core function is to lock the axial position of transmission components such as bearings, gears, and sleeves to prevent movement during operation. It is compatible with models such as 320D/336D excavators, 966K loaders, C7/C9 engines, and 140M graders, ensuring the accuracy and stability of shaft transmission and avoiding abnormal wear and noise of components. The following is structured technical and application information:

Core Technical Parameters
Item Details
Basic Attributes
Model 281-2922, Shaft Elastic Retainer (Snap Ring/Retaining Ring), compatible with 320D/336D excavator hydraulic pump drive shaft, 966K loader gearbox output shaft, C7/C9 engine rocker arm shaft, 140M grader drive axle shaft system, material is 65Mn spring steel (quenched HRC 48-52), surface anodized blackening treatment (salt spray resistance ≥48 hours), working temperature -40℃ to +150℃, single weight approximately 0.08 kg, used to lock the axial position of bearings/gears/sleeves to prevent shaft movement, rated clamping force ≥12 kN, elastic deformation ≤0.5 mm

Key Dimensions
Compatible shaft diameter 50.00 mm (groove diameter φ50.00 mm, tolerance h11, 0/-0.16 mm), snap ring inner diameter 48.50 mm (free state), outer diameter 54.00 mm, thickness 2.00 mm (tolerance ±0.05 mm), opening width 8.00 mm, end fillets R0.5 mm, groove depth 1.80 mm (tolerance +0.10/0 mm), circlip and groove fit clearance ≤0.05 mm, axial positioning accuracy after installation ≤0.03 mm

Material and Process: 65Mn spring steel → rolling → quenching (860℃ oil quenching) → tempering (420℃ air cooling) → precision grinding → oxidation blackening → opening forming. It possesses high elasticity, high wear resistance, and good fatigue resistance, suitable for medium-high speed and medium-load shaft positioning conditions.

Compatible Models: Cat 320D/336D excavator hydraulic pump drive shaft, 966K/972M loader gearbox output shaft, C7/C9 engine rocker arm shaft, 140M/160M… The grader drive axle shaft system is used to lock the axial position of the bearing inner ring, gear, or sleeve, preventing movement during shaft operation and ensuring transmission accuracy and stability.

Assembly Fit: Adapts to a standard elastic retaining ring groove (GB/T 894.1) for a φ50 mm shaft diameter. Groove diameter: φ50.00 mm (tolerance h11), groove width: 2.10 mm (tolerance + 0.10/0 mm). After installation, the retaining ring end face should fit snugly against the positioning component without gap. The retaining ring opening should avoid the direction of shaft force to prevent deformation and failure under stress.

Installation and Maintenance Points: Before installation, clean the shaft diameter groove, retaining ring, and mating components. Check the groove for burrs, rust, and deformation. Measure the groove diameter, width, and retaining ring dimensions to ensure the fit meets requirements. Installation tools must be compatible with the retaining ring outer diameter and opening size to avoid damaging the retaining ring or shaft diameter.

Use dedicated snap ring pliers (external snap type) to pry open the snap ring and gently place it into the groove, ensuring the snap ring is fully embedded without any misalignment. After installation, gently push the snap ring by hand; if there is no axial movement, it is properly installed. Do not use needle-nose pliers or other non-specialized tools to prevent snap ring breakage or deformation.

Maintenance Recommendations: Check the snap ring’s elasticity and positioning condition every 1000 hours. If deformation, breakage, wear, or oxide layer peeling occurs, replace it immediately. Avoid excessive axial loads on the shaft system daily to prevent snap ring overload failure, which can affect positioning accuracy and shaft system operational stability.