... with many famouse company certificate around the world which including SKF, SCHAEFFLER,NSK,KOYP,SNR and TPI etc. 3.Steel gradeTypeBearing steel ... A534. JIS G4805. DIN ENISO683-17Full hardening bearing steel , GCr15,SKF,100Cr6. SUJ2S1,SUJ2,SAE52100.Induction quenching bearing steel , S53CG . SAE1070M ...