CAT 437-2520 RETAINER

CAT 437-2520 is a Caterpillar original equipment manufacturer (OEM) elastic retainer for hydraulic cylinders/articulation pins. It is compatible with boom/stick cylinder lugs and connecting rod hinge ends in Cat 320D2/323D2 excavators and 966M loaders. Its core function is axial positioning and fixing of pins, bearings, or bushings to prevent axial movement of components. It is suitable for medium to heavy-duty applications. The following is professional structured information:

Core Technical Parameters (Professional Version)

Item Details
Basic Attributes
Model 437-2520, Type: External elastic retainer (shaft), Compatible with Cat construction machinery hydraulic cylinder lugs, boom/stick hinge ends, rocker arm pins, etc., Material: 65Mn spring steel (surface anodized blackening treatment), Free diameter: φ50 mm, Thickness: 2.0 mm, Width: 5.0 mm, Single weight: Approximately 0.08 kg, Compatible shaft diameter: φ50 mm, Operating temperature: – Temperature range: 40℃ to +150℃; Radial elastic force ≥8 kN; Ultimate shear strength ≥600 MPa; Fitting groove diameter φ48.5 mm; Groove width 5.2 mm

Key dimensions: Free diameter tolerance +0.10/-0.05 mm; Thickness tolerance ±0.05 mm; Width tolerance ±0.10 mm; Opening clearance 3.0-3.5 mm; Opening end chamfer 1.0×45°; Retaining ring edge roughness Ra≤0.8 μm; Radial runout ≤0.05 mm; Fitting shaft groove depth ≥2.2 mm; Groove fillet radius ≤0.5 mm

Material and process: 65Mn spring steel, quenched and tempered (hardness HRC 48-52); Surface oxide blackening layer thickness 5-8 μm for corrosion resistance; Elastic limit ≥1100 MPa; Fatigue life ≥10^6 The second cycle ensures a burr-free and crack-free opening, with stress-relief treatment at the edges to prevent breakage during installation.

Compatible with Cat 320D2/323D2/326D2 excavator boom-stick hinge pins, 966M/972M loader rocker arm pins, D6K/D7E bulldozer blade connecting shaft ends, and 320D2 hydraulic cylinder lug pins. These pins are used to secure the shaft to the bearing, preventing axial movement. They are compatible with φ50 mm shaft diameters and are installed in the shaft end groove, working in conjunction with the shaft end cap/bearing.

Assembly fit: Interference fit with the shaft groove (interference 0.10-0.15 mm). After installation, the flatness of the retaining ring end face with the shaft end should be ≤0.1 mm, and the axial movement should be ≤0.05 mm. Use a φ48 mm installation tool. External retaining ring pliers are used; hammering is strictly prohibited during installation to prevent deformation.

Installation and Maintenance Points:

Before installation, clean the shaft groove and check the retaining ring for deformation, cracks, or loss of elasticity. Use external retaining ring pliers to pry open the retaining ring, align it with the shaft groove, and slowly release it, ensuring the retaining ring is fully embedded in the groove without jamming.

After installation, check that the retaining ring fits tightly in the groove without looseness. Check every 800 hours. Replace the retaining ring immediately if deformation, decreased elasticity, or surface corrosion is observed.

Under heavy load/vibration conditions, check every 500 hours to prevent the retaining ring from falling off and causing component damage. When replacing, use original parts of the same model, ensuring size and elasticity match.