Bearing Protector

Bearing protector (also known as bearing isolator) prevents dust, water, and contaminants from entering the bearing housing, while keeping the lubricating oil inside. Premature bearing failure is one of the common causes of machine downtime, and contamination is the main culprit.

Operating principle

The protector consists of a rotating part that follows the shaft and a stationary part attached to the bearing cap. Between the two parts is a labyrinth or a small gap, combined with a drainage groove to allow leaking oil to return to the bearing housing and push contaminants out. Many types use a dynamic seal or a magnetic face to seal when the machine stops.

Common forms

• Non-contact labyrinth: simple, durable, low wear.
• Bearing isolator with dynamic seal: better sealing when the machine stops.
• Magnetic face type: high sealing, used in harsh environments.

Benefits

• Extend the life of bearings and lubricating oil.
• Reduce the number of machine stops due to bearing failure.
• Non-contact operation, so less wear on the shaft.
• Reduce oil leakage into the environment.

Applications

Pumps, motors, gearboxes, fans, and rotating machines in industrial plants. Many pump standards often prioritize non-contact bearing protection.

Correct installation

• Check the surface roughness, runout, and shaft diameter.
• Install the drainage port in the lowest position.
• Clean the bearing housing and use the correct type of oil.

Common issues

Shaft scratches, incorrect installation of the drainage port, incorrect clearance, or dirt accumulation that reduces the protective effect.

Consultation

SNS-VN supports consulting on bearing protectors according to shaft size and environmental conditions. Please contact us for a quote.