CAT 477-2023 Two Bolt Bearing Cap

CAT 477-2023 is a bearing cap (bearing cover) for Caterpillar hydraulic cylinder lugs/piston rod ends. It is suitable for axial fixing and sealing of bearings in Cat 336D2/349D excavator stick cylinders, 980M loader bucket cylinders, D8T bulldozer pusher cylinders, and other equipment. It prevents bearing movement, provides dust and water protection, and guides grease. It is suitable for high-pressure, impact, and dusty working conditions. The following is structured technical and application information:

Core Technical Parameters

Item Details
Basic Attributes
Model 477-2023, Flange-type Bearing Cap (Single), Material: 4140 Chromium-Molybdenum Steel (Quenched HRC32-38, Balanced Toughness and Strength), Surface Galvanized and Passivated (Corrosion Resistance, Salt Spray Resistance ≥96 Hours), Operating Temperature: -40℃ to +120℃, Single Weight: Approximately 0.8 kg, Used for axial positioning of bearings, sealing against dust and water, guiding lubricating grease, suitable for high pressure, impact, and dusty conditions.

Key Dimensions
Inner Diameter: 100 mm (Tolerance 0/+0.015 mm), Flange Outer Diameter: 140 mm, Flange Thickness: 12 mm, Total Length: 35 mm, Mounting Bolt Holes: 4×φ18 mm (Evenly Distributed, Center Circle Diameter 125 mm), Bolt Hole Countersunk Depth: 3 mm, Inner Hole Chamfer: 2×45°, Fit Tolerance: H7 (+0.030/0 mm)

Compatible Models This product is suitable for Cat 336D2/349D excavators (boom cylinder lug end), 980M loaders (bucket cylinder piston rod end), D8T bulldozers (bottom hinge point of the pusher cylinder), and 966M loaders (upper hinge point of the boom cylinder), and is compatible with 364-9897 sleeves and 191-2569 bearing assemblies.

Assembly Fit: The bearing should fit snugly against the outer ring face of the bearing. The inner bore should transition fit with the outer diameter of the sleeve (clearance 0-0.025 mm). The flatness of the flange face and the bearing housing contact surface should be ≤0.05 mm. Bolt preload torque: 85-95 N・m (10.9 grade M16 bolts).

Installation and Maintenance Points: Before installation, clean the bearing cap, sleeve, and bearing housing contact surfaces, checking for scratches, rust, and cracks. Measure the inner bore and sleeve outer diameter dimensions to ensure the fit clearance meets requirements. Install the O-ring (nitrile rubber, φ100×3.1). Apply Cat Moly Grease to prevent leakage.

Use bolts for installation. First, align the bearing cap with the sleeve and the outer ring of the bearing, and evenly tighten the four M16 bolts (tighten in 2-3 alternating stages, pre-tightening torque 85-95 N·m). Do not strike the flange face to prevent deformation. After installation, check the end face runout to be ≤0.05 mm to ensure no axial movement or leakage.

Maintenance: Check the bolt tightness and O-ring seal every 500 hours. If the O-ring is aged, damaged, or the bearing cap is deformed, replace it immediately. Replace it simultaneously with the bearing and sleeve to avoid poor fit.