Featured Troubleshooting Tip Video

What is burnishing and why is it important?

This snippet is from Ogura's full length troubleshooting online video. In this 42 second video segment, we show the factors that influence torque in a clutch or brake and why burnishing is important to achieve maximum torque from a clutch or brake.

There are other factors that influence the torque in a clutch or brake.

The surface friction can be influenced by contamination on the surface, temperature, and the condition of the surface.

Most mobile clutches do not have friction material and are steel on steel. To develop maximum contact area, the clutch or brake needs to go through initial cycling (burnishing) to wear down these high points.

Unburnished clutches can have a 20 to 50% reduction from their catalog rated torque, so a new mobile clutch that was unburnished can develop galling.

Galling is glazing of the surfaces which drops the coefficient of friction and reduces the amount of torque the clutch or brake can develop. A low hour slip failure is normally due to lack of or improper burnishing.