YA00047226 Original Excavator Bearing for Hitachi EX1900E-6LD

This bearing (part number YA00047226) is a key supporting component for the hydraulic system or slewing mechanism of the Hitachi EX1900E-6LD large electric driven crawler excavator. It is directly compatible with the EX1900E-6LD model and highly compatible with excavators of the EX1900-6LD series. As a genuine original accessory, this bearing is usually used in key parts such as slewing bearings, walking motors, or hydraulic pump shaft systems. It is a standard component for replacing worn or damaged bearings in the maintenance market, ensuring smooth operation and long service life of equipment under heavy load and high-speed rotation conditions.

This bearing belongs to a large heavy-duty rolling bearing, which is likely to be a single row or double row tapered roller bearing (based on the YA suffix often indicating non-standard shape), used to withstand huge axial and radial composite loads. It is forged from high carbon chromium alloy steel (such as GCr15), and after carburizing or overall quenching, precision grinding processing, the surface hardness of the raceway can reach HRC 60-64. The product structure includes an inner ring, an outer ring, rolling elements (rollers), and a cage, which may have sealing rings (such as 2RS or 2Z suffix) and lubrication holes. The production process includes material ultrasonic testing, rolling track contour accuracy testing (roundness ≤ 0.005 mm), clearance grouping selection, and strict fatigue life testing (usually requiring L10 life ≥ 10000 hours), ensuring high reliability, low friction, and impact resistance under extreme working conditions (load up to hundreds of tons, speed up to 10-20 r/min).

Key points for post maintenance and upkeep: 1 Regular inspection: Check the bearing for abnormal noise, vibration, or high temperature rise every 500 working hours (the shell temperature should usually be<80 ℃), and check the sealing ring for integrity and grease leakage every 1000 hours. 2. Lubrication and maintenance: Strictly follow the cycle specified in Hitachi's official manual (usually every 250-500 hours) and add the designated high-temperature resistant and extreme pressure lithium based grease (NLGI grade 2) through the oil nozzle until the old grease overflows from the sealing lip edge; Ensure that the lubricating grease is clean and prevent impurities from entering. 3. Installation specifications: Special hydraulic puller and press should be used for replacement, and direct hammering is strictly prohibited; Ensure that the bearing seat is clean, free of burrs, and installed according to the specified interference fit tolerance (usually H7/p6) and tightening torque.