Method for the production of a part of a rolling bearing
AssigneeSKF Engineering and Research Centre B.V.
InventorsJohn Michael Beswick, Michel Christian Gorenne, Antonin Ballay
Life of this patent
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Abstract
Method for the production of a part of a rolling bearing, such as a ring for a ball bearing. The starting material used is a grade of steel containing 0.90 1.00% C; at most 0.15% Si; 0.25-0.45% Mn; at most 0.0015% P; at most 0.010% S; 1.30-1.50% Cr; at most 0.15% Ni; 0.20-0.23% Mo; at most 0.20-0.23% Cu; at most 20 ppm Ti; at most 8 ppm O. Before subjecting this grade of steel to a quenching and tempering treatment, the shaped item is subjected to plastic deformation in the hot or cold state. The mechanical properties and in particular the anticipated life under severe stress improve as a result.
Claims10
Method for the production of a part of a rolling bearing, comprising the provision of a grade of steel containing, in % (by wt.),
- 0.90-1.00 C;
- at most 0.15 Si;
- 0.25-0.45 Mn;
- at most 0.015 P;
- at most 0.010 S;
- 1.30-1.50 Cr;
- at most 0.15 Ni;
- 0.20-0.23 Mo;
- at most 0.20 Cu;
- at most 20 Ti (ppm);
- at most 8 O (ppm),
- wherein a shaped item is produced from this steel, starting from a ferritic structure thereof, and is subjected to a heat treatment in order to increase the hardness at the surface of the item, followed by a machining after-treatment, if appropriate, characterised in that in that the shaped item is plastically deformed before the heat treatment.
Method according to one of the preceding claims, wherein said plastic deformation is carried out at elevated temperature.
Method according to one of the preceding claims, wherein said plastic deformation is carried out at room temperature.
Method according to one of the preceding claims, wherein said part is a ring that, starting from a smaller ring, is brought to the desired diameter by rolling.
Part of a rolling bearing produced from a grade of steel containing, in % (m/m),
- 0.90-1.00 C;
- at most 0.15 Si;
- 0.25-0.45 Mn;
- at most 0.015 P;
- at most 0.010 S;
- 1.30-1.50 Cr;
- at most 0.15 Ni;
- 0.20-0.23 Mo;
- at most 0.20 Cu;
- at most 20 Ti (ppm);
- at most 8 O (ppm),
- wherein said steel contains M23C6 carbides and has a grain size of between 5 and 8 μm.
Dependencies are inferred from the claim text.