4370876 Original Excavator Parts Arm Spacer for ZX200-3 ZX200 ZX240

This high-precision gap adjusting arm gasket (adjusting gasket) is specially designed for the front-end working device of Hitachi's medium and large excavators. The product strictly follows Hitachi's official part number 4370876 for standardized mass production, and is widely used in Hitachi's main excavator series such as ZX200, ZX210, ZX240, ZX250, ZX270, and ZX330. This gasket is mainly installed on the hinge end face of the pin shaft of core joints such as the boom and arm, and the arm and bucket. Accurate physical parameters and original factory level tolerance control enable it to be perfectly compatible with original shaft and liner components, specifically designed to eliminate axial end face clearances caused by long-term high load operations of the working device.

The arm gasket is made of high-strength spring steel or high-quality high carbon alloy steel as the base material, and has undergone precision cold rolling and digital stamping forming processes. The surface of the product has undergone deep quenching heat treatment and special wear-resistant coating modification, possessing extremely high surface hardness and excellent compressive and shear strength. The flatness of the gasket is extremely high, and the load-bearing surface is uniformly stressed. When subjected to severe alternating lateral impacts during excavation operations, it is not easy to undergo physical yielding or curling deformation. Its core physical properties focus on high rigidity and low friction coefficient, which can effectively reduce the direct rigid friction of mechanical joint end faces, lock the structural stiffness, and maintain the absolute stability of the working device.

In the later stage of equipment maintenance or major repairs of hinge parts, a vernier caliper should be used to accurately measure the joint clearance, and the axial clearance should be strictly controlled within the original factory safety boundary (usually less than 1mm) by combining 4370876 gaskets of different thicknesses. Before installation, the high entropy grease and rust on the hinge end face must be thoroughly removed, and heavy-duty lithium based grease should be evenly applied. In daily maintenance, the lubrication process of the whole machine should be combined to ensure that the gasket friction pair is fully lubricated; At the same time, it is necessary to regularly inspect the joint parts. Once the gasket is found to have edge cracking, eccentric wear, or excessive thickness deformation due to long-term service, it must be replaced in pairs in a timely manner to prevent unilateral eccentric load and damage to the boom body structure.