What action should be taken to increase clearance in a split Babbitt bearing?

• A. Shims are removed between the base and cap
• B. Shims are added between the base and cap
• C. The bearing caps are tightened
• D. The shaft diameter is reduced

Answer: (B)

To increase clearance in a split Babbitt bearing, adding shims between the base and the cap is the correct action. This is because shimming effectively raises the cap off the base, which increases the space or gap between the bearing surfaces and the shaft. This additional clearance can help accommodate thermal expansion, misalignments, or wear that might occur over time.

It's important to maintain an optimal clearance to ensure proper lubrication and minimize friction. If the clearance is too tight, it can lead to excessive heat and potentially damage both the bearing and the shaft. Using shims is a common practice in adjusting bearing clearances accurately to achieve the desired fit and performance when operating machinery.