Grease with false Brinelling protection

  • Grease with false Brinelling protection

    Posted by Werner Ruster on 31 August 2022 at 12:32 pm

    Dear all, how does a grease with false brinelling protection actually works ? How does the AW additive ZDDP do this ? For example Shell Rhodina grease BBZ and Klüber Kluperplex BEM 34-132 specially made for false Brinelling risks

    Rafe Britton replied 1 year, 9 months ago 2 Members · 2 Replies
  • 2 Replies
  • Rafe Britton

    31 August 2022 at 6:53 pm

    Hi @werner.ruster ! You can think of this as being a boundary lubrication problem. False brinelling is caused by slight movement of the rolling elements, so the speed is insufficient to develop any kind of lubricant film. The only thing that can protect you in these circumstances is some kind of antiwear additive – either surface active like ZDDP (that form a sacrificial layer on top of the element and race) or solid lubricants like MoS2 which insert themselves between the contact zones. Hope that makes sense.

    • Rafe Britton

      31 August 2022 at 6:54 pm

      Actually, I should also add that EP additives are generally ineffective for this kind of failure mode, as they typically require heat to chemically bond with metal surfaces.