CAT 8R-4145 15.9mm Inner Diameter Boot Sleeve

CAT 8R-4145 is a Caterpillar genuine axle sleeve (dustproof and wear-resistant protective sleeve), suitable for exposed shaft ends such as drive axle half shafts and gearbox output shafts of Cat 242D/252D skid steer loaders and 305.5E2 mini excavators. Its core function is to protect against dust, oil, and gravel impacts, and to protect the journal and bearing seals. The following is professional structured information:

Core Technical Parameters (Professional Version)

Item Details
Basic Attributes
Model: 8R-4145; Type: Axle sleeve (with double lip seal); Suitable for Cat 242D/252D skid steer loader drive axle half shafts and 305.5E2 excavator gearbox output shafts (shaft diameter φ40 mm); Material: Nitrile rubber (NBR) + galvanized steel frame; Inner diameter: φ40 mm; Outer diameter: φ55 mm; Length: 45 mm; Single weight: approximately 0.08 kg; Operating temperature: -40℃ to + 100℃, Protection rating IP65, Suitable shaft diameter φ40 mm (tolerance f7), Suitable shaft shoulder diameter ≥45 mm

Key Dimensions: Inner diameter tolerance ±0.1 mm, outer diameter tolerance ±0.2 mm, length tolerance ±0.5 mm, lip thickness 1.5 mm, steel frame thickness 1.0 mm, chamfer at both ends 0.5×45°, coaxiality ≤0.1 mm, sealing lip interference 0.1-0.2 mm, suitable shaft end protrusion length ≥15 mm

Material and Manufacturing Process: Main body is nitrile rubber (NBR, hardness 70 Shore A), with an embedded galvanized steel frame (anti-deformation), lip with dustproof lip + main sealing lip (double sealing structure), smooth surface without burrs, rubber to frame bonding strength ≥5 MPa, oil resistance rating ISO 1817 (resistant to hydraulic oil/gear oil), aging resistance rating ASTM D573 (≥1000 hours without cracking)

Compatible Models: Cat This product is designed for use with the drive axle half-shaft of the 242D/252D skid steer loader (serial number JCB1000-UP) and the gearbox output shaft of the 305.5E2 mini excavator (serial number JZH1000-UP). It is compatible with 205-4137 tapered roller bearing outer rings and 612-2097 single-row deep groove ball bearings to prevent dust and gravel from entering the shaft system and protect the bearing seals.

Assembly Fit: Interference fit with the shaft (interference 0.1-0.2 mm). After installation, the lip should not be flanged, the sleeve end face should fit snugly against the shaft shoulder, and axial movement should be ≤0.5 mm. The surface roughness of the matching journal should be Ra≤0.8 μm, and the journal should be free of rust/scratches (depth <0.1 mm).

Installation and Maintenance Points: Clean the journal before installation and check the sleeve for cracks/lip damage. Use a special installation tool (inner diameter φ40 mm, outer diameter φ55 mm). Smoothly push the sheath in (mm), never pull on the lip to prevent seal failure.

After installation, check the lip seal. Maintain every 500 hours. Replace immediately if the sheath shows signs of aging and cracking, lip wear (thickness <0.5 mm), or seal failure.

Maintenance recommendations: Avoid contact with sharp objects to prevent scratches. Regularly check the torque (15-20 N·m) of the sheath fixing bolts (if applicable) to prevent loosening and sheath detachment.