3088940 Original Excavator Parts Arm Shaft Pin Shaft for ZX200 ZX200-3 ZX240

Part number 3088940 is the official part number for Hitachi's original excavator arm shaft pin. This component is the core connection and force transmission element of various hinge points of excavator working devices (such as boom, arm, bucket), responsible for converting the thrust of hydraulic cylinders into excavation force and bearing huge alternating bending and shear loads. It is a key structural component to ensure smooth and reliable execution of excavator excavation, lifting, turning and other actions. As an original standard component, it is widely compatible with key articulated parts such as the boom base, boom connection, and bucket linkage of multiple Hitachi medium to large excavator models, such as the ZX200, ZX220, ZX250, ZX330 ZX series, as well as the EX200, EX220, EX300 EX series excavators.

The original arm shaft pin belongs to high-strength and high wear resistant alloy steel forgings. Its core function is to serve as the central axis of rotation under extreme working conditions (high impact, heavy load, frequent swinging), providing stable and reliable connections for structural components such as the boom and arm, and ensuring efficient transmission of force. As an original component, it is usually forged from high-quality alloy structural steel and undergoes precision quenching and surface intermediate frequency quenching treatment. This gives the pin core high toughness to resist impact, while the surface achieves high hardness to resist wear. Its structure is a precision machined cylinder, and some heavy-duty models may adopt a conical design to enhance fastening. Lubricating grease holes and oil grooves are usually designed on the pin shaft to facilitate regular lubrication and reduce friction and wear between it and the bushing.

The maintenance core of the arm shaft pin is to ensure sufficient lubrication, regular inspection of wear conditions, and standardized disassembly and assembly. Regular inspection and lubrication: It is necessary to strictly follow the cycle specified in the maintenance manual (usually every 100-250 working hours) and add the specified type of high-pressure grease through the oil nozzle on the pin shaft until the old grease is squeezed out from the edge of the sealing ring, ensuring sufficient lubrication. During installation, ensure that the oil hole on the pin shaft is aligned with the liner oil groove, and tighten the axial locking device to the specified torque. After installation, operate the working device several times and add lubricating grease again to ensure smooth lubrication channels. If the equipment operates in a dusty and muddy environment, the lubrication and inspection cycle needs to be shortened.