In this configuration an air passage is provided to the bearing area. The compressed air cools and lubricates the bearings and blows away any drilling debris extending the life of the bearing. This bearing configuration is commonly used in Blasthole Mining applications.
Semi-Sealed bearings for air circulation are similar to Open Air bearings, only difference being the bearing pack protected with an O-Ring Seal. The lubricant is filled into the bearing and sealed off. This prevents ingress of dirt into the bearing system and leakage of grease. This configuration is used for Mining applications with heavy water injection and ground water conditions.
In Sealed Journal bearing the Rollers inside the cone are replaced by a Floating Bush made out of special alloys which is silver plated. The bearing Pack is protected with an O-Ring Seal. The bearing lubrication and pressure compensator system is built in. The Floating Bush is highly resistant to heat and galling. Consequently these bearings are very durable and suitable for Mining, Raise Boring, HDD applications.