Heavy Machinery Japan Excavator Bearing: 39Q442120

Description

Basic Specifications

The 39Q442120 excavator bearing is a high-strength, impact-resistant rolling bearing specifically designed for Japanese heavy machinery. People commonly use it in the swing bearing systems or travel reducers of hydraulic excavators. The bearing typically features a double-row roller or angular contact ball structure, with an inner diameter of approximately 200 mm, an outer diameter of around 250 mm, and a width of about 32 mm. Compact yet durable, it is manufactured from high-quality bearing steel (GCr15 or equivalent), heat-treated and precision-ground to ensure excellent wear resistance and fatigue strength. With optional precision classes P6 or P5, it meets the demanding requirements of accuracy and reliability.Its double-sealed protection design prevents mud, dust, and moisture intrusion effectively.This design ensures stable performance even in harsh environments like high temperature, dust, or humidity.

Product Advantages

The 39Q442120 bearing stands out for its superior load capacity and shock resistance. Reinforced raceway geometry and optimized contact angles enable it to withstand substantial axial, radial, and tilting moment loads simultaneously, ensuring smooth operation under complex working conditions. The low-friction cage design reduces energy loss and heat generation, thereby extending service life. Its excellent lubrication adaptability supports both grease and centralized lubrication systems, minimizing maintenance intervals and downtime while improving overall operational efficiency and reliability.

Product Applications

People widely use this bearing in Japanese and international brand excavators. They install it in swing assemblies, travel reduction gears, track drive systems, and boom connections.Beyond excavators, it is also suitable for other heavy-duty construction equipment such as loaders, cranes, bulldozers, and rotary drilling rigs. Designed for extreme working environments with heavy load, strong impact, and high dust levels, the 39Q442120 bearing is a core component that ensures the stable and long-term performance of heavy machinery.