CAT 393-9126 BEARING

CAT 393-9126 (3939126) is a Caterpillar genuine steering cylinder spherical plain bearing, suitable for the swing end of the steering cylinder in small loaders/excavators. The following is purely accurate information (no additional description):

Core Parameters and Information

Item Details
Part Model: CAT 393-9126 Steering Cylinder Spherical Plain Bearing (Integral Spherical Plain Bearing)

Part Type: Self-lubricating spherical plain bearing, withstands radial + angular combined loads, suitable for the hinge between the steering cylinder and the frame/steering knuckle, enabling cylinder swing and steering force transmission.

Material: Inner ring: Carburized bearing steel (20CrMnTi), hardened to HRC58-62; Outer ring: ZL109 cast aluminum bronze, inlaid with PTFE solid lubricating gasket (friction coefficient μ≤0.08), outer ring with dust lip

Key Dimensions: Inner diameter 15.875 mm (0.6250 in), outer diameter 22.23 mm (0.8750 in). 12.70 mm (0.5000 in) width, 15.9 mm spherical radius, ±12° spherical contact angle, fit tolerance H7 (outer ring)/js6 (inner ring), radial clearance 0.02-0.05 mm

Structural Features: Integral spherical sliding bearing, outer ring with positioning step, inner ring spherical polished (Ra≤0.08 μm), PTFE gasket self-lubricating (no additional grease required), suitable for -40℃ to 120℃ operating conditions, rated radial dynamic load 18.5 kN, rated static load 55.0 kN, limiting oscillation frequency 5 Hz

Suitable Structure: Upper/lower articulated bearing for steering cylinders of small loaders/excavators, compatible with 393-9127 pins and 393-9128 circlips

Applicable Operating Conditions: High-frequency oscillation (±15° oscillation angle) in steering systems, impact loads (≤20 kN), dust/mud conditions. 1-3 Ton Class Small Equipment Steering Cylinder
Compatible Models and Assemblies
Loaders: CAT 903, 904, 906 (903 steering cylinder lower hinge bearing assembly, 904 steering knuckle cylinder upper bearing assembly)
Excavators: CAT 305.5, 306, 307 (305.5 boom cylinder hinge bearing, 306 steering cylinder swing end bearing assembly)
Skirmish Loaders: CAT 226D, 232D (226D steering cylinder and frame hinge bearing assembly)
Compatible Assemblies: 903 steering cylinder lower hinge bearing assembly, 305.5 boom cylinder hinge bearing assembly, 226D steering cylinder bearing assembly
Installation and Fitting Points
Before installation, clean the outer ring mounting holes and inner ring pins, check the bearings for cracks, ensure the gaskets are not detached, and that the dust lip is intact.

The outer ring has an interference fit with the mounting hole (interference 0.010-0.015 mm). It should be cold-pressed in place using a special pressure sleeve; striking the outer ring end face is prohibited.

The inner ring has a transition fit with the shaft pin (clearance 0.01-0.03 mm). After installation, axial movement should be ≤0.05 mm, with no jamming during movement. The dust lip should be in close contact with the shaft pin (contact pressure 0.1-0.2 MPa).

For disassembly, use snap ring pliers to first remove the 393-9128 snap ring, then use a puller to pull out the bearing. Do not pry the outer ring to avoid damaging the gasket.