Case-Hardened 20CrMnTi HK Series Drawn Cup Needle Roller Bearings

Case-Hardened 20CrMnTi HK Series Drawn Cup Needle Roller Bearings are dimensioned to ISO 3245 / DIN 618-1 / GB/T 290 exactly as the standard version is: the material changes the properties, never the envelope. What it does change — none of its own; protected in service exactly as through-hardened bearing steel is, magnetic and the service range similar to through-hardened rings — about +120 °C without special stabilization — is set out below with the full size chart.

Why Case-Hardened 20CrMnTi for HK Series Drawn Cup Needle Roller Bearings

Chosen for shock loading and for heavy ring sections, where a tough core resists the cracking a fully through-hardened section would not survive. In a hk series drawn cup needle roller bearings it is the steel of the rings and, in most designs, of the rolling elements.

Carburizing puts the hardness where the rolling contact is and leaves the core tough, so the ring can absorb shock and heavy section stresses that would crack a through-hardened ring. It is the usual choice for large roller bearing rings and for anything that gets hit rather than merely loaded.

Material Properties

Service Limits

The case has a depth, and that depth is a design limit: load high enough and the maximum shear stress moves below the hardened case into the softer core, where the surface then collapses. That is why case depth is specified against the rolling element size and the load, and why a case-hardened ring is not simply a tougher version of a through-hardened one.

Alternatives and When to Switch

Through-hardened GCr15 is the alternative and the default: it is used wherever the section is modest and the load is steady, which is most of the catalog. Case-hardened rings earn their place under shock and in large sections.

Sizes of HK Series Drawn Cup Needle Roller Bearings Available in Case-Hardened 20CrMnTi