CAT 378-9593 Bearing – Needle(Debris Resistant)

CAT 378-9593 is a Caterpillar stamped outer ring full complement needle roller bearing with chip-resistant seal. It is suitable for shaft ends/joints in the gearboxes, final drives, or slewing mechanisms of loaders and excavators, providing contamination-resistant sealing for heavy radial loads and harsh operating conditions. The following is professional structured information.

Core Technical Parameters (Professional Version)

Item Details
Basic Attributes Model 378-9593, anti-chip full complement needle roller bearing, single weight 0.58 kg, 2 pieces per unit (double-sided shaft end), compatible shaft diameter φ65 mm, radial clearance 0.09–0.13 mm, with double-lip dust seal + labyrinth anti-chip structure, compatible with Cat 1U-8888 grease

Key Dimensions Inner diameter φ65.0 mm (tolerance H7: 0–+0.030 mm), outer diameter φ82.0 mm (tolerance r6: +0.034–+0.056 mm, interference fit), total length 32.0 mm (tolerance ±0.1 mm), sealing lip diameter φ65.5 mm, dust lip diameter φ66.0 mm, needle roller diameter φ4.0 mm × length 28.0 mm, cage thickness 2.5 mm mm
Material and Manufacturing Process: Outer ring is made of 10CrMo910 alloy steel sheet (HRC 58–62), needle rollers are made of GCr15 bearing steel (HRC 60–64), cage is made of PA66+GF30 reinforced nylon, seal is made of nitrile rubber (NBR, oil resistant -40℃ to +120℃), outer ring surface is oxidized and blackened (salt spray resistance ≥120 h), needle rollers are precision ground (Ra≤0.8 μm)

Performance Parameters: Operating temperature -40℃ to +120℃, radial load ≥32 kN, limiting speed 2600 rpm (oil lubrication), chip protection rating IP65 (dust particle size ≥10 μm non-intrusive), sealing lip wear resistance ≥5000 h, lubrication cycle 200 hours

Compatible Models: Loaders 950M/966M, excavators 320GC/323GC, for gearbox output shaft ends and final drive planetary carrier shaft ends, compatible with φ65 mm shaft diameter + φ82 mm bearing housing bore, and compatible with Cat 4W-7000 shaft seals.

Installation and Maintenance Points:
Before installation, clean the bearing housing bore and shaft surface, checking for burrs/rust. Apply Cat 105-7900 anti-seize compound to the outer ring. Press in using a special sleeve (pressing force 20–25 kN), ensuring the sealing lip is in close contact with the shaft surface (contact pressure 0.3–0.5 MPa).

Clearance Control: After installation, use a dial indicator to check the radial clearance. If <0.07 mm or >0.15 mm, the bearing must be replaced to prevent needle roller seizure or excessive wear.

Maintenance Requirements: Add Cat 1U-8888 grease every 200 hours (40–50 g per area). Check the sealing lips for damage/leakage. If dust accumulation is present, clean and replace the seal.

Troubleshooting: If abnormal noise/excessive temperature rise occurs, check for needle roller wear or insufficient lubrication. Disassemble and replace the needle roller assembly, and clean the oil passages to ensure unobstructed lubrication.