CAT 625-7420 Hydraulic Tilt Cylinder Bearing

CAT 625-7420 is a self-lubricating radial spherical plain bearing designed by Caterpillar for the hinged joints at both ends of the hydraulic tilt cylinders of loaders and excavators’ buckets/booms. It is used to withstand radial loads and provide bidirectional angular compensation (±5°), suitable for the swing and support requirements of medium- and high-pressure hydraulic systems (≤35MPa). The following is the structured core information:

Core Parameters
Item Details
Basic Information
Model 625-7420, self-lubricating radial spherical plain bearing, suitable for hydraulic tilt cylinder lugs/pivots, withstands radial loads + angular deflection, self-lubricating and maintenance-free, installation method is interference fit (outer ring interference fit with lug bore, inner ring clearance fit with pivot)

Compatible Models
CAT 950/962/972 loaders, 336/349 excavators, suitable for lugs at both ends of bucket tilt cylinders and boom tilt cylinders

Material and Manufacturing Process
Outer ring bearing steel (GCr15, hardened HRC) 61-65), Inner ring bronze alloy (CuSn8P, with graphite self-lubricating insert), uncoated surface, accuracy class P0, radial clearance C3 group, static angular deflection ±5°

Key Dimensions: Inner diameter 50mm (1.969in), outer diameter 75mm (2.953in), width 25mm (0.984in), inner ring wall thickness 5mm, outer ring wall thickness 7.5mm, weight approx. 0.58kg

Functional Parameters: Radial dynamic load 85.2kN, radial static load 128.6kN, coefficient of friction ≤0.08 (dry friction), operating temperature -40℃ to +120℃, limiting oscillation frequency ≤10 times/minute

Matching Components: Fitting pivot diameter 50mm (h8 tolerance), lug hole diameter 75mm (H7 tolerance), matching seal 4T-0523, retaining ring 1W-7020, bolts 8T-4121 Installation and Maintenance Points

Preparation before installation: Clean the clevis hole and pivot surface to remove burrs and oil; check that the clevis hole roundness is ≤0.015mm and the interference fit between the outer ring and the clevis hole is 0.02-0.03mm; use a dedicated press-fitting tool, and strictly prohibit striking the inner or outer ring to avoid damaging the self-lubricating layer.

Installation steps: Use a hydraulic press to smoothly press the bearing outer ring into the clevis hole; pass the pivot through the inner ring, ensuring the inner ring can rotate freely; check that the bearing end face and clevis fit tightly without looseness, and the axial clearance is ≤0.2mm; no additional lubrication is required (self-lubricating design).

Maintenance and replacement: Check the bearing’s oscillation flexibility and wear every 3000 hours. Replace the bearing if jamming occurs, the inner ring wear exceeds 0.5mm, or the self-lubricating insert falls off; avoid overload impacts that could cause the outer ring to crack, and prohibit high-speed oscillation without lubrication.