4274552 Original Excavator Hydraulic Retaining Ring for Hitachi ZX220W-7

This original hydraulic retaining ring (part number 4274552) is designed and used in conjunction with the Hitachi ZX220W-7 (approximately 22 ton class) wheel excavator. The ZX220W-7 machine has a working weight of approximately 21900kg and comes standard with the HIOS IV intelligent hydraulic system. This retaining ring is mainly used for axial fixation of shaft elastic retaining rings in core components such as hydraulic pumps and rotary motors, to prevent them from loosening under severe vibration and high load conditions. Its precise C-shaped cross-sectional diameter and thickness perfectly match the design specifications of the original machine shaft groove. This part may also be compatible with models of the same series such as ZX220-7 and ZX240W-7, which use similar hydraulic component fixing structures. However, it is recommended to refer to the original parts manual or service system before replacement.

This product is a black C-shaped metal buckle ring, made of high-strength alloy steel (such as 65Mn or SK5) precision stamped and processed by quenching and tempering heat treatment. Its hardness can reach HRC 47-55, and it has both high elasticity and excellent fatigue strength. Its unique structure can provide uniform radial clamping force, effectively locking the shaft retaining ring. The flat head ear pieces designed at both ends have circular holes, making it easy to use specialized snap pliers (such as internal expansion or hole pliers) for safe and convenient disassembly and assembly. The surface is usually treated with blackening or phosphating, which has good rust prevention and wear resistance. As an original component, its dimensional tolerances and mechanical properties have been rigorously tested, which is a key safety component to ensure the reliability of axial positioning of ZX220W-7 hydraulic transmission components.

It is recommended to combine regular maintenance of the equipment every 1000 hours of operation, or check the condition of this retaining ring when repairing hydraulic pumps and motors. Focus on checking for visible cracks, plastic deformation, weakened elasticity (manifested as the inability to restore the original tension after disassembly), or severe corrosion. Once an abnormality is detected, it must be immediately replaced with original 4274552 parts, and the use of substitute products with dimensions that do not match or insufficient strength is strictly prohibited. Thoroughly clean the shaft groove before installation to ensure that there are no impurities; During installation, it is necessary to use a suitable tool to fully and smoothly press the buckle into the bottom of the groove, and confirm that it is firmly seated without any lifting or misalignment. Daily storage should be placed in a dry environment to avoid collisions and maintain its geometric shape and performance.