4720025 Original Excavator BRG Bearing for ZX330-3G

Part number 4720025 is the original roller bearing provided by Hitachi for the ZX330-3G series medium-sized hydraulic excavator. This component is mainly used for the support wheels or sprocket wheels of the track walking mechanism, and is a key load-bearing joint that supports the weight of the entire machine, withstands ground impacts, and ensures the smooth operation of the track. Its universal models usually cover three series of same platform models including ZX330-3G, ZX330-3, ZX350-3, etc. As the core load-bearing bearing of the original factory, its inner and outer diameters, width, and roller inner cavity and journal are precisely matched

This product is a heavy-duty deep groove ball bearing, with high carbon chromium bearing steel used for the inner and outer rings and balls. After quenching and precision grinding, it presents a silver gray metallic luster as shown in the picture, with high hardness and wear resistance. Internally, high-strength nylon or steel plate stamping cages are used to ensure even distribution of ball bearings. Its design is specifically designed to withstand the enormous radial impact load of the track system, with an accuracy level usually not lower than P6, a working temperature range of -30 ℃ to+120 ℃, and can adapt to harsh working conditions such as mud, sand, and high vibration in the wild.

Installation specifications: 1 Cleaning: Before installation, the roller cavity, shaft neck, and new bearings must be thoroughly cleaned with a cleaning agent to ensure no sand residue. 2. Heating installation: It is recommended to evenly heat the new bearing with an oil bath to 80-100 ℃, and then quickly and smoothly install it into the roller cavity. Direct tapping is strictly prohibited. 3. Lubrication: Fill the bearing with sufficient high-temperature and extreme pressure resistant lithium based grease before installation. 4. Sealing: Ensure that the floating oil seals or skeleton oil seals on both sides are installed in place, which is the key to preventing mud and water from entering and maintaining lubrication.