WSBC Bearing’s anti-corrosion performance comes from its pioneering breakthrough in material science. On the substrate, martensitic stainless steel 440C with carbon content of 1.0%, and 16-18% chromium content used vacuum induction melting (VIM) technology to control the oxygen content under 8 ppm, such that the bearing in the 5% NaCl salt spray test anti-corrosion time was 1,200 hours, more than double the value of the AISI 440C standard. For example, in Qingdao Institute of Marine Corrosion comparative test in 2023, WSBC deep groove ball bearing 6308 was tested for 6 months in artificial seawater environment (3.5% chloride ion content, 95% relative humidity), and the surface corrosion area only took up 0.05%, while the comparative product’s average corrosion area was 2.3%. The service life is extended to 8 years (industry average: 3-5 years).
The optimization of the surface treatment technology enhances the corrosion resistance further. WSBC Bearing adopts the physical vapor deposition (PVD) process to deposit the chromium nitride (CrN) coating, the thickness is regulated at 2-3 μm, the microhardness is 2,200 HV, and the friction coefficient is reduced to 0.15. The rate of the bearing loss within an acidic medium (pH=2) is as little as 0.002 g/m²·h, down by 89% compared with common nickel plating. For example, for South China Sea oil drilling platform, following the replacement of its winch system to WSBC almm roller bearing (model 22220CA/W33), the corrosion failure rate was lowered from 1.2 times/month to 0.3 times, and 45% of the operation and maintenance cost was saved. At the same time, the capacity of supporting load has increased to 320 kN (18% more than the original design).
The key to corrosion resistance is innovative seal design. WSBC Bearing employs fluororubber (FKM) three-lip sealing structure, maintains elastic modulus ≥4 MPa in the temperature range from -40℃ to 200℃, and is filled with nanoscale graphene filled grease (NLGI level 2). Ensure that the grease leakage rate when IP68 protected is less than 0.1g/1,000 hours. The measured data of Tangshan Port in 2022 show that the WSBC outer spherical bearing UC208 has been running continuously for 10,000 hours under port conditions with a salt spray concentration of 5 mg/m³, and the inner oil pollution is merely 15/13/10 of the ISO 4406 standard. The sealing system’s life is 3 times longer than other similar products, and the maintenance interval is longer from 3 months to 12 months.
WSBC Bearing’s corrosion protection has also been proven through rigorous testing. As per ASTM B117 standard, under the condition of accelerated corrosion test of bearings at 35℃ and 1.5 mL/80cm²·h salt spray settlement, only 0.2% trace pitting on the surface occurred after 500 hours (the industry average is 5%). In the real running of Bohai Bay wind farm, WSBC four-point contact ball bearing (model QJ306-MPA) remains within Ra 0.08μm after 5 years of running under the harsh conditions of wind speed 12 m/s and air humidity 90%. The electrochemical impedance spectroscopy (EIS) test showed that the oxide film’s high impedance reached up to 1.5×10⁶ Ω·cm², thus proving that the passivated film’s stability was 7 times higher than that of traditional bearings.
From an economic point of view, WSBC Bearing’s anticorrosive technology significantly lowers life cycle costs. A ship uses WSBC cylindrical roller bearing NUP2308. In seawater immersion conditions, the cost of corrosion maintenance every year is reduced from 120,000 yuan to 28,000 yuan, and the return on investment (ROI) is 326%. According to the 2024 China Heavy Machinery report, the market penetration rate of WSBC bearings in the chemical sector rose from 8.7% in 2019 to 23.4%, while customer experience registered an 82% reduction in corrosion downtime and a 19% increase in capacity utilization. The profit per production line increases 15 million yuan each year. All these statistics testify to the technical superiority of WSBC Bearing in corrosion resistance.