Bearings might look simple but they’re exact components. Every part, every tiny detail, plays a role in keeping your machinery running smoothly. One of those critical details? Clearance.
It’s not just a technicality—it’s the difference between a bearing that works flawlessly and fails catastrophically.

What Is Bearing Clearance, Anyway?

Bearing clearance is the space inside a bearing that allows the rolling elements (balls, rollers, etc.) to move. It might be small, but it’s meaningful. There are two types to know:
Radial Clearance: The gap that allows movement perpendicular to the bearing’s axis. Think side-to-side wiggle.
Axial Clearance: The gap that allows movement along the axis. Think back-and-forth play.
That tiny space makes all the difference in how the bearing performs under pressure.

Why It Matters

Here’s why you can’t ignore bearing clearance:
Smooth Operation:
Proper clearance keeps the rolling elements moving freely. No grinding. No unnecessary friction. Just smooth, efficient motion.
Adapts to Heat:
Bearings heat up when they’re running. Materials expand. Without enough clearance, that expansion can make the bearing seize. With too much, it becomes sloppy. Clearance gives the bearing room to breathe, so to speak.

Distributes Loads:
Bearings are designed to evenly spread loads across all rolling elements. The right clearance ensures this happens. Too tight or too loose? You’ll get uneven load distribution, and that’s bad news.
Reduces Noise and Vibration:
Ever heard a bearing scream? It’s not pretty. Improper clearance leads to noise, vibration, and unnecessary wear.
Protects Other Components:
A bearing with the right clearance does its job quietly and efficiently. But when it’s off, it can transfer stress to nearby parts—shafts, housings, gears—and cause a domino effect of damage.

What Happens When Clearance Is Off?

Too Tight?
Increased friction.
Overheating.
Rapid wear.
Worst-case scenario: bearing seizure and total failure.
Too Loose?
Wobble and instability.
Poor load distribution.
Increased vibration and noise.
Premature wear and a much shorter lifespan.
In both cases, your machinery suffers. And so does your bottom line.

Why Clearance Gets Overlooked

Here’s the thing. People often focus on the bearing size or type and forget about clearance. But it’s not just a “set it and forget it” detail. It’s impacted by:
Operating Conditions: High speeds, heavy loads, or extreme temperatures demand specific clearance levels.

Shaft and Housing Fit: A tight fit can reduce clearance. A loose fit can increase it.
Thermal Expansion: Bearings and surrounding parts heat up and expand differently. Clearance compensates for this.
Miss this step and you’re setting yourself up for trouble.

How to Get Clearance Right

Follow the Specs:
Start with the manufacturer’s guidelines. They know their bearings better than anyone.
Measure Precisely:
Tools like feeler gauges and micrometers are your best friends here. Don’t eyeball it.
Match the Fit:
The fit between the bearing, shaft, and housing matters. A tight fit reduces clearance. A loose fit increases it. Plan accordingly.
Think About Heat:
If your machinery operates in high temperatures, use a clearance that can handle thermal expansion without binding.
NSAR Bearings: Your Clearance Experts
At NSAR bearings we know clearance isn’t just a technical detail—it’s essential. Here’s how we help:
High-Quality Bearings: Designed with precision and built to perform.
Custom Solutions: Need specific clearance levels? We offer OEM customization to fit your exact requirements.
Expert Advice: Our team helps you choose the right bearing for your application—every time.
Global Reach: With offices in the U.S. and warehouses worldwide, we deliver quickly, no matter where you are.
Clearance might seem small, but it has a massive impact. Too tight, and you’re overheating and grinding to a halt. Too loose, and you’re wobbling into instability. Getting it right means smoother operation, longer bearing life, and fewer headaches.
Need bearings? Need advice? We’re here for you.