🔍 Key Concepts

• Antifriction (rolling-element) bearings construction: inner race, outer race, rolling elements • How bearings are mounted on shafts vs. housings to prevent unwanted movement • Why alignment and interference fits are important for bearing life

💭 Think About

• Think about which bearing part actually needs to rotate with the shaft and which part should stay fixed with the housing. • Consider what would happen to the bearing surfaces and wear patterns if either race were free to spin loosely where it is mounted. • Ask yourself whether precision bearings are tolerant of misalignment, or whether misalignment tends to cause overheating and premature failure.

✅ Before You Answer

• Identify which race is normally mounted tightly on the shaft, and which race is normally mounted tightly in the housing. • Consider whether good bearing practice allows any race to be free to turn where it is seated, or whether a secure fit is preferred. • Confirm whether alignment is generally considered critical or not when installing high‑speed rotating machinery bearings.