CAT 501-7924 COLLAR

CAT 501-7924 ​​is a Caterpillar genuine axle locating collar used in the hydraulic or transmission systems of excavators, loaders, and other equipment. It provides axial positioning, anti-loosening, and clearance compensation for components on the axle. The following are precise original factory specifications and application information, excluding replacement parts (Cat®…).

Core Technical Parameters

Item Details
Part Model CAT 501-7924 ​​(Shaft Collar/Locking Ring)

Product Type: Shaft positioning component for engineering machinery, used on the shafts of hydraulic pumps, motors, or transmission gearboxes to prevent axial movement of bearings, gears, and other components. Suitable for medium and high pressure and vibration conditions.

Material: 42CrMo alloy structural steel, heat treated (hardness HRC 28–32), blackened surface + anodized treatment, excellent rust prevention and wear resistance.

Key Dimensions: Inner diameter 65 mm (2.56 in), outer diameter 85 mm (3.35 in), width 18 mm (0.71 in), inner hole fit tolerance H7, parallelism of both end faces 0.02 mm.

Mounting Structure: Sliding shaft collar, keyless design, positioned by the shaft shoulder and locking nut/circlip, suitable for shaft diameters of 65 mm.

Unit Weight: Approx. 0.48 kg (1.06 lbs)

Operating Parameters: Suitable pressure ≤ 35 MPa, operating temperature -30℃ ~ +120℃, suitable for mineral oil, hydraulic oil, and other media.

Structure and Core Characteristics

High-Precision Positioning: 42CrMo material and tempering process ensure dimensional stability, allowing precise control of axial clearance of shaft components (0.05–0.15 mm), preventing component displacement due to vibration.

Anti-Loosening and Wear-Resistant: Blackened surface treatment enhances wear resistance; sliding fit structure with locking parts effectively prevents relative rotation between the collar and shaft, suitable for long-term heavy-duty operation.

Strong Compatibility: Standard internal bore tolerances and width dimensions, compatible with hydraulic pumps, travel motors, or gearbox shafts of various Caterpillar equipment, requiring no additional machining for installation.

Compatible Models and Application Scenarios

Compatible Equipment: Hydraulic main pumps, swing motors, or gearbox shafts of 320D2/323 excavators, 966H/972H loaders, D6T bulldozers, etc.

Core Applications: Installed on the inner side of the bearing on the shaft or on the end face of the gear, it is fixed to the shaft shoulder and locking device to limit the axial displacement of components, ensuring transmission accuracy and hydraulic system stability. Suitable for medium and high pressure and high frequency vibration conditions.

Installation and Maintenance Points

Installation: Clean the inner hole of the collar and the shaft mounting surface to remove oil, rust, and impurities. Check the collar for deformation, cracks, or end face damage.

Use cold-fit sliding fitting to ensure a tight fit between the collar and the shaft without gaps. After installation, use a dial indicator to check the end face runout; ≤0.03 mm is acceptable.

When using the lock nut, tighten according to the torque specified in the equipment manual to prevent the collar from loosening. The torque is generally 65–75 N·m (compatible with M64×2 nuts).

Maintenance: Check the fit between the collar and the shaft every 1500 hours. Tighten or replace immediately if loosening or wear is observed.

During equipment maintenance, simultaneously inspect the surface and end face of the collar. Replace the collar if wear exceeds 0.2 mm or cracks appear to prevent positioning failure.

Avoid contact with corrosive media. Change the hydraulic oil/gear oil regularly to prevent collar corrosion from affecting positioning accuracy.