CAT 204-5117 RETAINER

CAT 204-5117 (2045117) is a retainer for Caterpillar hydraulic cylinders/linkage mechanisms. It is primarily designed for the boom cylinder, stick cylinder, or connecting rod pin ends of CAT 320D/323D excavators, 980G loaders, and other models. It is used for axial positioning and fixing of bearings, seals, guide sleeves, and other components, preventing axial movement and loosening of components under high-pressure conditions, and ensuring the stable operation of hydraulic actuators and transmission mechanisms. The core information is as follows:

Core Technical Parameters
Item Details
Part Model: CAT 204-5117 (2045117) Retainer (with bolt holes + positioning steps + anti-loosening groove)
Core Material: 40Cr alloy steel, overall tempered (HB 240–270), surface galvanized passivation + Dacromet coating, corrosion resistant + anti-loosening, suitable for humid and dusty working conditions in construction machinery
Key Dimensions: Outer Diameter 85 50 mm inner diameter, 12 mm thickness, 3 mm positioning step height, 4 M12×1.5 bolt holes evenly distributed circumferentially (70 mm hole spacing), 3 mm wide and 1.2 mm deep anti-loosening groove, suitable for shaft diameter 50 mm. Weight: Approx. 0.45 kg. Compatible models: CAT 320D/320D2/323D/329D excavators (boom cylinder/stick cylinder/bucket cylinder shaft end), 980G/966G loaders (tilt cylinder/steering cylinder), D9G bulldozers (lift cylinder), used to fix cylinder piston guide sleeves, connecting rod bearing end caps, and pin thrust components. Working compatibility: Maximum working pressure 35 MPa, compatible with mineral oil-based hydraulic oil (ISO VG). 46) Capable of withstanding axial thrust and vibration loads under reciprocating motion.
Core Functions and Structural Features
Axial Positioning and Anti-migration: The positioning step fits snugly against the shaft shoulder, and four bolt holes are secured with high-strength bolts to prevent axial movement of components such as guide sleeves and bearings during cylinder reciprocating motion or connecting rod transmission, avoiding damage to seals and component collisions, and ensuring operational accuracy.

Anti-loosening and Corrosion Resistance: The anti-loosening groove can be equipped with locking shims or anti-loosening wires to adapt to vibration conditions; the Dacromet coating is resistant to salt spray ≥960 h, preventing rust caused by humid environments on construction sites and avoiding bolt jamming and disassembly difficulties.

Precise Installation and Fit: Overall machining accuracy IT7, end face runout ≤0.03 mm, tight fit with shaft end and cylinder end cover, no positioning deviation, ensuring component coaxiality, and reducing operational friction and leakage risks.

Heavy-duty adaptable design: Made of 40Cr material with a yield strength ≥800 MPa after tempering, it can withstand the high-pressure thrust of the hydraulic cylinder and the impact load of the transmission mechanism, preventing deformation and breakage of the retainer. Suitable for heavy-duty working conditions in mining and infrastructure.

Installation and Maintenance Points
Installation Specifications: Clean the retainer, shaft end, and mounting surface, removing burrs, iron filings, and oil stains. The flatness of the mounting surface should be ≤0.05 mm. Ensure bolt hole threads are clean and undamaged to avoid stress concentration after installation.

Use 10.9 grade M12×1.5 bolts, tightening symmetrically to a torque of 65–75 N・m. Install locking washers and insert them into anti-loosening grooves to prevent bolt loosening.

After installation, check that the axial clearance of the components is ≤0.08 mm, that there is no abnormal vibration or noise during operation, and that the hydraulic cylinder has no leakage, ensuring positioning and sealing effects.

Maintenance Recommendations: Check every 800 working hours: for deformation and cracks in the retainer, loose bolts, and peeling coating. Replace immediately if any problems are found.

When replacing parts, prioritize original parts or highly compatible reinforced versions to ensure that the material, dimensional accuracy, and coating meet standards. Avoid using ordinary carbon steel retainers as this can cause component movement and premature seal damage.

Simultaneously check shaft end wear and seal aging; replace them as needed to ensure the overall stability of the cylinder and transmission mechanism.