In the rapidly developing power industry, bearings play a crucial role in numerous electric motors, especially in terms of insulation during motor maintenance. Japanese Shaft Research Seiko ZNY, with its extensive experience, shares the following key points:

Common methods of bearing insulation include using insulated bearings and applying insulated bearing housings.

Insulated Bearings: These usually involve coating the inner and outer rings with ceramic materials using plasma spraying technology, maintaining excellent insulation even in moist environments. Bearings with ceramic rolling elements offer outstanding current blocking ability, effectively achieving insulation.

Insulated Bearing Housings: This method typically involves lining the inner hole of the end cover bearing housing with a PTFE film to isolate current transmission between the bearing and the end cover.

When maintaining electric motors, regardless of the insulation method used, the following points should be noted:

• Control of shaft and bearing housing tolerances: Ensure that the bearing can rotate flexibly without any hindrance after being pressed in. If it does not rotate smoothly, it may be due to oversized bearings or tolerance issues.
• Bearing assembly method: Insulated bearings are high-precision products and should be assembled using professional tools to avoid direct impacts. Ensure even force distribution when pressing in bearings to prevent damage.
• Prevent assembly foreign objects: Ensure cleanliness during bearing assembly and prevent foreign objects, such as metal chips, from entering the bearing. Also, do not apply oil or grease inside the bearing housing.
• Prevent paint rust: Especially in enclosed motors, choose high-quality insulating paint and ventilate thoroughly after drying to prevent paint rust.