Bearing 5204

The 5204 bearing is a double row angular contact ball bearing with standard dimensions of 20mm (bore) x 47mm (OD) x 20.6mm (width). When sourcing, you must specify the internal clearance (e.g., C3 for high-speed applications), the contact angle (typically 30 degrees), and the cage material (Nylon, Steel, or Brass). For high-precision machinery, ensure the tolerance class meets ISO P6 or P5 (ABEC-3 or ABEC-5) to minimize vibration and heat generation.

Selection depends on the environment: Use ZZ (metal shields) for high-speed, clean environments with low friction requirements, or 2RS (rubber seals) for dusty or moist conditions to prevent contaminant ingress. Ensure the supplier uses high-quality synthetic grease (like Mobil or Shell) if the bearing is 'sealed for life,' as lubrication failure is the leading cause of premature bearing fatigue.

Reliable suppliers must adhere to ISO 9001:2015 for quality management. For specific industries, look for IATF 16949 (Automotive) or RoHS/REACH compliance if the bearings are used in consumer electronics or exported to the EU. Always request a Material Test Report (MTR) to verify the use of high-carbon chromium steel (GCr15/SAE 52100), which ensures the necessary hardness of HRC 60-65.

Due to its ability to handle simultaneous radial and axial loads in both directions, the 5204 is widely used in agricultural machinery, pumps, gearboxes, and air conditioning compressors. Its rigid design makes it ideal for applications requiring high axial stiffness and precise shaft guidance.

Counterfeit bearings are a major risk in the B2B sector. To mitigate this, source directly from verified manufacturers on Made-in-China.com who provide factory audit reports. Request a SGS or TUV third-party inspection before shipment to conduct a hardness test and noise level (Z1, Z2, Z3) verification, ensuring the steel is not low-grade carbon steel passed off as chrome steel.

Bearing prices are highly sensitive to raw material (steel) market fluctuations. Negotiate based on annual volume rather than single-order quantity to secure lower pricing. For the 5204 model, a typical MOQ ranges from 100 to 500 pieces; however, you can negotiate a 'blanket order' where the supplier stocks the inventory and releases it in batches to improve your cash flow.

Bearings are heavy and prone to oxidation during sea freight. Ensure the supplier uses VCI (Volatile Corrosion Inhibitor) paper or vacuum-sealed plastic packaging. For bulk shipments, specify fumigated wooden pallets and reinforced outer cartons to prevent box crushing. For shipping to the US or Europe, clarify the Incoterms (FOB or DDP) to manage customs duties and 'Anti-Dumping' taxes that may apply to specific bearing categories.

Always utilize Secured Payment services on Made-in-China.com to ensure funds are only released after proof of shipment. Avoid direct wire transfers to private accounts. Before the final payment, request a pre-shipment video inspection showing the batch's dimensional accuracy using digital calipers and the smoothness of rotation.