What should be done to reduce clearance in a split Babbitt bearing?

To reduce clearance in a split Babbitt bearing, removing shims between the base and cap effectively decreases the gap between the bearing and the shaft. Shims are thin pieces of material inserted between the components to adjust spacing; by removing them, the bearing halves can come closer together. This adjustment compresses the bearing material around the shaft, leading to a tighter fit and reduced clearance.

This is significant because proper clearance ensures adequate oil film formation for lubrication, which is essential for bearing performance and longevity. A well-maintained clearance level minimizes friction and wear, leading to smoother operation of the machinery.

In contrast, adding shims would increase the space, which is not desirable when the aim is to reduce clearance. Replacing the bearing material would be a more drastic measure and not typically necessary for simple clearance adjustments. Increasing the shaft diameter is also not a practical solution, as it may require extensive changes to equipment and doesn’t directly address the fit of the existing bearing.