CAT 1P-4146 1.3880\ Inner Diameter Needle Roller Bearing

The CAT 1P-4146 is a single-flange sealed lubricated track roller assembly for Caterpillar’s mini excavator tracked chassis. It bears the weight of the machine and guides the track movement. It is compatible with mini excavators such as the 301.7 CR and 302.7 CR, and features heavy-duty wear resistance and long-lasting sealing performance to ensure stable chassis operation. The following is structured technical and application information:

Core Technical Parameters

Item Details
Basic Attributes
Model 1P-4146, Type: Single-flange sealed lubricated track roller, Material: 40Mn2 alloy steel (wheel surface hardened, hardness HRC50-55), Single weight: approximately 8.2 kg, Operating temperature: -30℃ to +120℃, Design life: ≥8000 hours (normal working conditions), Sealing system: double-lip skeleton oil seal + dust ring, Lubrication method: lifetime sealed lubrication (containing lithium-based grease), Protection rating: IP67, Suitable for mini excavator tracked chassis

Key Dimensions
Wheel surface diameter: 120 mm (tolerance 0/-0.20 mm), Flange diameter: 140 mm (tolerance 0/-0.30 mm), Shaft diameter: 35 mm (tolerance 0/-0.015 mm), Overall length: 180 mm (tolerance 0/-0.50 mm), Wheel width: 60 mm, Mounting hole spacing: 150 mm mm, bolt specification M12×1.75 (2 pieces), contact gap with track shoe 2-3 mm, radial runout ≤0.10 mm
Compatible Models and Accessories: Compatible with Cat 301.7 CR, 302.7 CR, 303 CR mini excavators, with matching 12-9904 bolts and 1P-4147 end caps. Can be used in combination with 1P-4148 bushings and 1P-4149 sealing rings.
Performance Parameters: Rated load ≥35 kN, coefficient of friction ≤0.008 (under good lubrication conditions), wheel surface hardening depth 3-5 mm, sealing pressure ≥0.3 MPa, impact resistance ≥80 J/cm², anti-derailment design (single flange height 10 mm)
Structural and Performance Advantages: 40Mn2 alloy steel wheel surface is deeply hardened, achieving a hardness of… HRC50-55, with strong wear and impact resistance, is suitable for the complex working conditions of mini excavators, extending the service life of the track rollers.

The double-lip skeleton oil seal + dust ring sealing system, with an IP67 protection rating, effectively prevents the intrusion of impurities such as mud and water. The lifetime sealing and lubrication design reduces maintenance frequency and lowers operating costs.

The single flange structure precisely guides track movement, preventing track derailment. The mounting hole spacing and bolt specifications are compatible with mini excavator chassis, making installation convenient and requiring no complex adjustments, improving maintenance efficiency.

Installation and Maintenance Points: Before installation, clean the mounting surface and check the track rollers for cracks and deformation. Tighten M12×1.75 bolts in a diagonal sequence with a torque of 25-30 N·m. After installation, check the track tension to ensure good contact between the track rollers and track pads without abnormal gaps.

Before operation, check if the track rollers rotate smoothly and without abnormal noise. If there is any jamming, troubleshoot immediately. During operation, avoid prolonged unilateral load-bearing to prevent uneven wear on the wheel surface.

Maintenance: Check the track roller seal every 500 hours. If oil leakage, wheel wear exceeding 2 mm, or abnormal rotation noise occurs, replace immediately. When replacing, check the track shoes, guide wheels, and other components simultaneously to ensure the overall performance of the chassis. Do not mix track rollers of different models.