3112457 Original Excavator Bearing for ZW220

Part number 3112457 is an original bearing specially designed by Hitachi for the ZW220 wheel excavator. The universal model of this component is this part number, mainly used for key rotating parts such as the rotary support, walking mechanism or working device hinge point of ZW220. As an original precision transmission component, its inner and outer diameters, width, installation seat holes, and shaft diameter are precisely matched. It is strictly prohibited to use bearings with different accuracy levels to avoid abnormal noise, abnormal wear, and even structural damage.

The inner and outer rings and ball bearings are made of high carbon chromium bearing steel, which has been quenched and precision ground to present a silver gray metallic luster and delicate texture in the picture, with high hardness and wear resistance. Internally, a black high-strength nylon or steel plate stamping cage is used to ensure even distribution of ball bearings. Its accuracy level is usually P6 or higher, capable of withstanding high radial loads and certain axial loads, with a high limit speed, and able to adapt to the vibration and impact of excavator operation. The working temperature range is -30 ℃ to+120 ℃.

Installation specifications: 1 Cleaning: Before installation, the bearing itself, installation shaft, and bearing seat must be thoroughly cleaned with a lint free cloth and cleaning agent to ensure that there are no sand particles or metal shavings. 2. Heating installation: For interference fit, it is recommended to evenly heat the bearing with an oil bath to 80-100 ℃ and quickly and smoothly install it on the shaft. Direct tapping is strictly prohibited. 3. Lubrication: Fill the bearing raceway with a sufficient amount of specified high-temperature grease before installation. 4. Alignment and fastening: During installation, ensure that the bearings are absolutely aligned with the shaft and seat to avoid generating unbalanced loads. Use a torque wrench to tighten the locking nut or end cap to the specified torque. Inspection cycle: Check the installation site for any abnormal temperature rise, noise, or oil leakage every 250 working hours.