CAT 7M-0699 Brace Bearing Cap

CAT 7M-0699 is a Caterpillar shaft end dust cover/sealing cover, mainly used on the shaft ends of pins, bearing seats, or hydraulic components of excavators, loaders, and other equipment. It serves to prevent dust, dirt, and leakage. It is compatible with the boom/stick hinge pins, track guide wheel shaft ends, and other parts of Cat 320D/336D excavators, 950M loaders, and other models. It is a key protective component for protecting internal components and extending service life. The following is structured technical and application information:

Core Technical Parameters

Item Details
Basic Attributes
Model 7M-0699, Type: Shaft end dust cover/sealing cover, Material: Outer layer 42CrMo alloy steel (hardness HRC45-50), Inner layer: Nitrile rubber (NBR, hardness Shore A 70-75), Single weight approximately 0.35 kg, Applicable temperature -30℃ to +100℃, Oil resistance meets SAE 10W-40 standard, Aging resistance ≥5000 hours

Key Dimensions
Compatible shaft diameter 50 mm (tolerance 0 to -0.012 mm), Outer diameter 75 mm (tolerance +0.015 to +0.025 mm), Height 18 mm (tolerance ±0.10 mm), Sealing lip thickness 3 mm, Compression 0.5-1.0 mm, Number of bolt holes 4, Hole diameter 8 mm, Hole spacing circle diameter 60 mm mm, chamfer 1 mm × 45°
Compatible Models and Applications: Compatible with Cat 320D, 323D, 336D excavators, 950M, 966M loaders. Used for boom and stick hinge pins, stick and bucket connection pins, track guide wheel shaft ends, and hydraulic cylinder piston rod ends. Matching parts include bolts, washers, and O-rings. Protection rating: IP65
Performance Parameters: Sealing type is lip seal + O-ring combination. Static sealing pressure ≤0.5 MPa, dynamic linear velocity ≤1.5 m/s, coefficient of friction ≤0.08 (oil lubrication), radial runout after assembly ≤0.05 mm, salt spray resistance ≥240 hours without rust.
Structural and Performance Advantages:
Composite Protection: The outer alloy steel layer provides rigid support and impact resistance. The inner NBR rubber lip seal tightly fits the shaft surface, effectively preventing dust, mud, and moisture from entering the internal bearings/pins, while also preventing grease leakage.

Precise Fit: High dimensional accuracy and precise bolt hole positioning ensure a tight fit with the shaft end and housing after installation, preventing loosening and making it suitable for complex working conditions such as vibration and impact in engineering machinery.

Long-lasting Durability: NBR rubber is oil-resistant and aging-resistant, while alloy steel is corrosion-resistant, making it suitable for long-term outdoor operation environments, reducing maintenance frequency and costs.

Easy Installation: Bolt fixing eliminates the need for special tools, allowing for quick on-site disassembly and assembly, suitable for emergency repairs and routine maintenance.

Installation and Maintenance Points: Before installation, clean the shaft end, housing, and dust cover, checking for burrs and cracks. During installation, ensure the rubber lip is undamaged, tighten bolts evenly (torque 8-10 N·m), control the sealing lip compression to 0.5-1.0 mm, and ensure smooth rotation.

Perform a 1-hour trial run, checking for leaks and abnormal noises. Every 500 hours, check the sealing condition, clean surface oil and dust, and replace the dust cover when the rubber lip shows signs of aging, cracking, or wear exceeding 0.3 mm.

When replacing parts, original parts should be used first to ensure that the inner and outer diameters, sealing lip thickness and compression amount meet the standards. After installation, check the condition of the bolts and O-rings to prevent loosening or seal failure that could damage internal components.