XB00014097 Original Excavator Boom Bushing for ZX890-7G

The part number XB00014097 is the original boom root bushing provided by Hitachi for the ZX890-7G series (with a total weight of approximately 90 tons) ultra large hydraulic excavator. It is a large and sturdy cylindrical metal liner used to connect the key hinge point between the excavator boom and the lower frame, and is one of the joints with the highest load-bearing capacity and most complex stress on the entire machine. Its universal model is dedicated to the ZX890-7G model, and may have interchangeability on the same platform model (such as ZX870) of this ultra large tonnage equipment, but it is strictly prohibited to use it for other models with different tonnages. As the core structural component of the original factory, its inner diameter, outer diameter, length, and heat treatment process require extremely high fitting tolerances with the boom and pin shaft, which is the cornerstone of ensuring equipment stability and service life.

This product is a bimetallic composite liner, with a thick walled cylindrical body and a high-strength alloy steel (such as 42CrMo) as the matrix. The inner hole surface is coated with a significant layer of golden wear-resistant material (usually copper lead alloy or high-performance engineering plastic liner, such as DU/DP material). This "steel back+wear-resistant layer" structure not only provides overall support strength, but also achieves excellent self-lubricating properties and low friction coefficient through the inner lining. The spiral or linear grooves visible on the inner wall in the picture are channels for lubricating grease, ensuring that the grease can be evenly distributed throughout the entire friction surface. The golden coating on its surface may be a galvanized or tin plated anti rust layer. The liner undergoes precision grinding and heat treatment to ensure dimensional stability and can withstand significant radial impact loads and sustained swinging friction.

Installation specifications (extremely critical): 1 Cleaning and inspection: Before installation, the pin holes of the boom and lower frame must be thoroughly cleaned with fine sandpaper and cleaning agent to ensure that there are no burrs, rust, or residual old bushings. Measure the actual size of the hole with an inner diameter dial gauge to ensure an interference fit with the outer diameter of the liner. 2. Press in installation: A hydraulic press or specialized liner installation tool must be used to ensure that the liner is absolutely vertical and smoothly pressed into the installation hole. It is strictly prohibited to strike directly with a hammer to avoid deformation or damage to the lining. 3. Lubrication preparation: After installation, extreme pressure lithium based grease must be added through a grease nipple until the grease overflows from both ends of the liner, ensuring that the lubrication channel is full.