Here are the questions that most customers often asked, please refer to them, if you have any other questions, please contact us.
The material used in our most slewing ring bearings is 50Mn&42CrMO,42CrMo is better than 50M due to it has high strength and toughness, and good hardenability.
42CrMo=America ASTM 4140/4142 =England BS 708M40/708A42/709M40 =Fance NF40CD4/42CD4 =GERMAN DIN 41CrMo4/42CrMo4=JANPAN JIS SCM4=ISO 683/1 3
50Mn=America ASTM 1050/1052 =England BS030A52/080M50=France NF XC48 = Japan JIS S53C
we have 2 machines, one can do overall quenching, the other is single quenching.
As our experience, the reason is the raceway quenching has some problem, like hardness is not enough, the quenching depth is not qualified, no enough grease .etc.
1 year warranty, if any broken, new one will be sent for replaced.
we often measure the old sample and produce new one for our customers.