🔍 Key Concepts

• How bearing wear is physically measured on a main propulsion turbine • What type of tools or devices actually come into direct contact with the bearing or journal • Differences between gauges that measure distance/clearance and materials used to check fit or crush

💭 Think About

• For each device listed, ask yourself: Does this tool realistically get placed on or in the bearing area to show how much material has worn away or how much clearance has changed? • Think about which of these tools is commonly used for checking clearances by being compressed or deformed by the machinery parts themselves. • Consider whether any of the tools are typically used for structural measurements elsewhere (like on foundations or alignments) rather than directly on turbine bearings.

✅ Before You Answer

• Verify which device is specifically associated with measuring clearance or crush by deformation in rotating machinery bearings. • Check whether a bridge gage is normally used on turbine bearings or more for alignment/deflection checks in other components. • Confirm how a micrometer depth gage is used and whether it would be placed directly in the bearing to show wear or is more for dimensional checks of surfaces or grooves.