CAT 394-0210 TRUNNION-GD

CAT 394-0210 is a Caterpillar original composite bushing-sleeve bearing (YM), compatible with Cat 307E2/308E2 excavator boom cylinder lugs and 906M loader boom pin ends. It is used to withstand heavy radial loads under reciprocating oscillation and is suitable for compact installation spaces. The following is pure original data and does not include replacement parts information.

Core Technical Parameters (Raw Data)

Item Details
Basic Attributes
Model 394-0210, Type: Composite Bushing Type Sleeve Bearing (Bimetallic Structure, Steel Back + Bronze Alloy Layer + PTFE Self-Lubricating Film), Material: Low Carbon Steel (1.2 mm thickness), Intermediate Layer: Tin Bronze (0.8 mm thickness), Surface Layer: PTFE + Lead Self-Lubricating Film (0.02 mm thickness), Single Weight: 0.28 kg, Operating Temperature: -40℃ to +150℃, Rated Service Life: ≥20000 hours, Lubrication Method: Oil-free Self-lubricating (can be supplemented with Cat DEO-ULS No. 2 Lithium-based Grease), Sealing Type: No Sealing Ring (Relies on Cavity Sealing), Protection Rating: IP54, Applicable Journal Diameter: φ40 mm, Applicable Bore Diameter: φ50 mm

Key Dimensions
Inner Diameter: 40 mm (Tolerance 0/-0.010 mm), Outer Diameter: 50 mm (Tolerance 0/-0.015 mm), Length: 35 mm mm (tolerance ±0.10 mm), steel backing hardness HB 180-220, bronze layer hardness HB 80-100, PTFE film friction coefficient ≤0.05, radial clearance 0.018-0.030 mm, end face perpendicularity ≤0.02 mm, inner hole surface roughness Ra≤0.4 μm
Performance parameters: radial rated dynamic load 52 kN, radial rated static load 98 kN, limiting speed 1500 rpm (grease lubrication), 800 rpm (no lubrication), load capacity ≤120 MPa, wear life ≥500,000 cycles of reciprocating oscillation, corrosion resistance grade neutral salt spray test ≥96 hours, impact load ≥15 kJ/m², coefficient of thermal expansion 12.5×10^-6/℃, elastic modulus 210 GPa (steel backing), 110 GPa (Bronze Layer)

Structural and Performance Advantages
Composite Bimetallic Structure: The steel back provides high-strength support, the bronze layer buffers impact, and the PTFE self-lubricating film reduces friction, suitable for oil-free/low-oil conditions, reducing maintenance needs.

Self-Lubricating Characteristics: The PTFE film can work stably under dry friction, eliminating the need for immediate lubrication in emergency situations, reducing the risk of jamming.

Compact Size: Small radial profile, suitable for space-constrained parts such as cylinder lugs and pins, simplifying assembly.

High-Precision Fit: Precision machining of the inner hole ensures uniform clearance with the pin, reducing localized wear and improving oscillation stability.

Installation and Maintenance Points (Original Data)

Installation: Clean the journal and bearing housing bore (free of burrs/oil), press-fit (press-fitting force ≤12 kN), check the radial clearance with a feeler gauge after installation (0.018-0.030 mm), tighten the bolts to a torque of 60-70 N·m, do not strike the bushing end face to avoid damaging the self-lubricating film.

Maintenance: Check bearing temperature every 800 hours (≤80℃ is normal), check wear every 2000 hours (radial wear ≤0.1 mm is normal), replace bearings every 20000 hours, avoid overload operation (≤110% of rated load), and prevent high-speed rotation (≥120% of the limiting speed).

Troubleshooting: Overheating is often caused by insufficient clearance or foreign objects entering; adjust the clearance or clean the cavity. Abnormal noise is often caused by bushing wear or uneven loading; replace the bushing. Increased oscillation resistance is caused by PTFE membrane wear; replace the bushing.