CAT 9S-4775 14.29mm Inner Diameter Needle Roller Bearing

CAT 9S-4775 is a Caterpillar original single-row cylindrical roller bearing, suitable for valve core supports or low-load drive shafts in control valves/pilot valves, used for radial positioning and low-friction rotation. It weighs approximately 0.12 kg and is sold in single-station units. The following is professional structured information:

Core Technical Parameters (Professional Version)

Item Details
Basic Attributes: Model 9S-4775, Cylindrical Roller Bearing (with cage), Inner Diameter φ25 mm, Outer Diameter φ47 mm, Width 12 mm, Radial Clearance C3 (0.012-0.023 mm), Operating Temperature -40℃ to +120℃

Key Dimensions: Inner Ring Width 12 mm, Outer Ring Width 12 mm, Roller Diameter φ5 mm, Length 10 mm, Cage Material PA66+GF25, Center Bore Positioning Tolerance +0.01/-0.005 mm, End Face Runout ≤0.02 mm

Material and Manufacturing Process The bearing rings/rollers are made of high-carbon chromium bearing steel (SUJ2, HRC 60-62), surface carburized and quenched (hardened layer 0.8-1.2 mm), grease filling 1.8 g (Cat 106-3962 lithium-based grease), rotational accuracy P5 grade, limiting speed 6000 rpm.

Compatible Models: Suitable for the main control valve core bearing of Cat 320GC/330GC excavators and 938K/950GC loaders, or the pilot pump drive shaft support of 3054/3066 engines. Also used for the output shaft of small hydraulic motors.

Assembly Fit: The shaft and inner ring have an interference fit (0.005-0.01 mm), and the bearing housing and outer ring have a clearance fit (0.01-0.02 mm). The inner ring should be heated during installation. Hot-fit at 80-90℃, do not strike the outer ring.

Installation and Maintenance Points:
Before installation, clean the bearing and mounting holes, checking for rust and burrs. After heating the inner ring, quickly fit it onto the shaft shoulder for positioning. Gently press the outer ring into the bearing housing (interference ≤ 0.01 mm) to avoid damage to the raceway.

Ensure the bearing end face is in close contact with the shaft shoulder (clearance ≤ 0.01 mm). After assembly, manually rotate the bearing without jamming; radial runout ≤ 0.03 mm, axial runout ≤ 0.02 mm.

Maintenance Cycle: Check rotational flexibility every 2000 hours. Replace the bearing if abnormal noise/temperature rise is detected. It is recommended to replace the bearing during a major overhaul of the control valve to prevent valve core jamming and subsequent malfunction.