Why You Should Never Skip Cleaning Bearings Before Installation

In the world of precision machining, spindle bearings play a critical role in ensuring both machine performance and part quality. Even high-quality bearings can fail prematurely — not due to defects, but because of improper installation practices.

This real-world case clearly demonstrates how a small mistake during setup — skipping the cleaning step — led to costly downtime and bearing failure.

Background: Unexpected Bearing Failure

A customer reported that the spindle bearings they had purchased from us failed shortly after installation. They suspected a product quality issue and requested an on-site investigation.

Our technical team responded immediately and conducted a full inspection at the customer’s facility.

On-site Inspection: No Manufacturing Defects Found

Upon examining the failed bearings, we found:

• No cracks, deformation, or material issues
• No signs of poor heat treatment or production flaws

It was clear that the problem wasn’t with the product itself.

After reviewing the installation process, we identified the root cause:

The bearings were installed without being cleaned. The customer applied new grease directly over the factory-applied anti-rust oil.

What Went Wrong?

The anti-rust oil is only meant to protect the bearing during storage and transport — it is not a lubricant.

By applying grease on top of this oil, the following issues occurred:

• The two substances did not mix well
• The grease could not properly adhere to the bearing surfaces
• During high-speed operation, the grease was easily flung off
• This left the bearings running with little or no lubrication

As a result, wear accelerated quickly, leading to early bearing failure.

 Correct Procedure: Clean Before Installation

We walked the customer through the proper installation steps for open (non-sealed) spindle bearings:

1. Clean thoroughly – Use a suitable solvent to remove all anti-rust oil.
2. Dry completely – Wipe dry with a lint-free cloth or use filtered compressed air.
3. Apply the right grease – Use manufacturer-recommended spindle grease, applied evenly.
4. Install carefully – Handle the bearings gently to avoid damaging internal components.

We demonstrated each step and helped them reinstall the bearings correctly.

Since then, the machine has been running smoothly with no further issues.

Key Takeaway

This case is a strong reminder:

Even the best spindle bearings require correct handling to reach their full service life.
Skipping basic steps like cleaning may seem minor, but it can have major consequences.

 Need Help with Bearing Installation or Maintenance?

If you're unsure about how to install, clean, or maintain your spindle bearings, don’t hesitate to contact our support team. We offer expert guidance and on-site assistance to help you get the most out of your equipment.

Let’s keep your machines running efficiently — together.