638-2Z

The 638-2Z is a 638 series small double-sided dust-proof sealed deep groove ball bearing (standard specification with an inner diameter of 8mm). Its core function is to provide low friction, high stability, and long life rotational support for small equipment with limited space and high requirements for cleanliness protection. With a compact structure size of 8mm inner diameter, 16mm outer diameter, and 5mm width, it inherits the basic advantage of deep groove ball bearings that can simultaneously bear radial loads and a small amount of bidirectional axial loads. Through the dual protective design of the 2Z type double-sided stamped steel dust cover, it forms a tight sealing barrier, effectively blocking dust, impurities from entering and internal lubricating oil leakage, significantly reducing the risk of wear caused by contaminants, and extending the maintenance-free period and overall service life of the bearing. It is made of high-carbon chromium bearing steel (GCr15) for the raceway and rolling elements, and after professional quenching and heat treatment, its hardness reaches HRC60-64, possessing excellent wear resistance, fatigue resistance, and dimensional stability. Combined with lightweight stamped steel cage and high-performance lithium-based lubricating grease, the friction coefficient is low and the operating noise is small. It can meet the requirements of high rotational speed operation under medium to low loads without complex maintenance, ensuring the smooth operation of the equipment. This bearing is precisely matched with "compact size + double-sided dust-proof + reliable performance", and is widely used in small motors, power tools, office equipment, light industrial machinery, micro transmission mechanisms, handheld portable equipment, precision instruments and meters, small electronic devices, plastic and rubber machinery (small components), and laboratory equipment, providing efficient and long-lasting support and protection for various small rotating mechanisms with requirements for installation space, cleanliness protection, and operational stability.