Preventing Motor Bearing Damage from Shaft Current with the AEGIS® Ring

Electric motors are the workhorses of modern industry, powering everything from pumps and fans to conveyor belts and heavy machinery. But these vital components are not immune to wear and tear, and one common problem that can lead to premature motor failure is bearing damage caused by shaft current.

Shaft current is a type of electrical discharge that occurs when there is a voltage potential between the motor shaft and the bearing, resulting in the flow of electrical current through the bearing. This current can cause a range of problems, including pitting and fluting of the bearing surfaces, which can lead to premature wear and failure.

Shaft current

Motor shaft current can have several harmful effects on bearings, including:

1. Bearing pitting and fluting: Electrical discharges can cause tiny pits and flutes to form on the bearing surfaces, leading to premature wear and failure.

2. Bearing noise and vibration: Shaft current can cause the bearing to vibrate and produce a high-pitched noise, which can be annoying and distracting to operators.

3. Increased maintenance and downtime: If bearings are damaged due to shaft current, they will need to be replaced or repaired, which can be time-consuming and costly.

4. Reduced motor efficiency: Electrical arcing caused by shaft current can reduce motor efficiency and increase energy consumption, leading to higher operating costs.

5. Safety hazards: In extreme cases, shaft current can create a safety hazard by causing sparks or explosions in explosive or hazardous environments.

The AEGIS® Ring is an effective solution for protecting bearings from the harmful effects of motor shaft current.

The AEGIS® Ring protects the motors bearings and prevents fluting and bearing failure and the High-Frequency Ground Strap (HFGS) ensures a reliable path to system ground.

One solution to this problem is the AEGIS® Ring, a patented grounding device that is installed around the motor shaft to conduct harmful shaft voltages away from the bearings and safely to ground. The AEGIS® Ring is designed to prevent the buildup of static electricity on the shaft and divert any electrical discharges away from the bearings, protecting them from damage.

The AEGIS® Ring is made of a conductive microfiber material that creates a low-resistance path to ground, allowing electrical currents to flow safely away from the bearings. It is easy to install and can be retrofitted to existing motors, making it a cost-effective solution for preventing motor failure due to shaft current.

Grounding Path
The AEGIS® Ring conducts harmful shaft voltages away from the bearings to ground. Voltage travels from the shaft , through the conductive microfibers, through the housing of the ring, through the hardware (or conductive epoxy) used to attach the ring to the motor, to ground

In addition to protecting bearings from damage, the AEGIS® Ring can also improve motor performance by reducing the risk of electrical arcing and noise. By ensuring that the electrical current flows safely through the AEGIS® Ring, rather than through the bearing surfaces, the device can help to reduce wear and tear on the motor and extend its overall lifespan.

Overall, the AEGIS® Ring is an effective solution for protecting motors from the damaging effects of shaft current. By providing a low-resistance path to ground for electrical currents, the AEGIS® Ring can help to prevent premature bearing failure and improve motor performance, making it an essential tool for industrial maintenance and reliability professionals.

For further information, you can obtain the Bearing Protection Handbook by downloading it.

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