High-Quality Bearing Materials: GCr15 Seamless Steel Tubes with Certified Inspection Reports

At DSBR Bearing Factory, we know that high-quality bearings begin with exceptional raw materials. That’s why we strictly source GCr15 seamless bearing steel tubes, a premium-grade material renowned for its high carbon and chromium content, excellent hardenability, and outstanding wear resistance.

According to the latest Inspection Certificate dated April 21, 2025, provided by our trusted supplier, all batches fully comply with GB/T18254-2016 and YB/T4146-2016 standards.

Key Highlights from the Material Inspection Report:

Steel Grade: GCr15
Condition: Annealed (Spheroidizing Annealing for machinability)
Outer Diameter Range: 50.9 mm – 52.7 mm
Wall Thickness: 4.95 – 6.1 mm
Chemical Composition (Avg.):

C: 0.95–0.96%, Si: 0.23–0.25%, Mn: 0.25–0.29%
Cr: 1.41–1.44%, Ni, Cu, Mo, S, P: All within strict limits

Hardness (HB): 186 – 193
Ultrasonic Testing, Eddy Current, Decarburization Depth: All qualified
Microscopic Structure: Spheroidized Pearlite, Ferrite band ≤ Grade 2
Non-metallic Inclusions (A, B, C, D types): All within Grade 1 limits
Wall Thickness Deviation: ±0.02 mm
Dimensional Tolerance & Surface Finish: Fully compliant with international standards

Why It Matters for Global Bearing Buyers

Whether you are in the automotive, mining, or heavy machinery sector, using certified bearing-grade GCr15 steel tubes guarantees:

Higher fatigue life and rotation accuracy
Consistent hardness and microstructure
Reliable performance in high-load and high-speed conditions

In-House Quality Assurance

At DSBR automotive bearings factory, we re-inspect every incoming raw material using advanced equipment such as spectrometers, roundness testers, ultrasonic flaw detectors, and metallographic analyzers. This ensures that every bearing we produce meets or exceeds ISO and IATF 16949 requirements.

Partner With a Bearing Factory That Cares About Quality from the Source

We don’t just manufacture bearings—we build reliability from the ground up. For those seeking china automotive bearings, DSBR offers unparalleled quality and performance, ensuring your applications run smoothly and efficiently. By choosing DSBR, you partner with a team that values transparency, traceability, and excellence.