Contents
What causes motor bearing failure?
According to a recent study, up to 80 percent of bearing failures are caused by improper lubrication. This includes insufficient lubrication, use of improper lubricants or excessive temperatures that degrade the lubricant.
What is the most important mode of bearing failure?
The two main failure modes of a bearing are wear and fatigue. Ball and roller bearings which are well lubricated , perfectly sealed and running at moderate load and speed, will not exhibit sufficient wear that will cause a failure even after long service.
What happens when motor bearings fail?
One of the costliest potential consequences of bearing failure is damage to surrounding equipment, such as shafts, bearing housings and electric motors. This can happen as a direct result of the bearing failure, or during the reactive maintenance that is performed as a result.
How does bearing failure occur in an electric motor?
Motors that are transported without the rotor shaft held securely in place can be subjected to vibrations within the bearing clearance that could damage the bearings. Similarly, if a motor is at a standstill and subjected to external vibrations over a period of time, the bearings can also become damaged.
How do I know if my bearings are damaged?
Metal-to-metal contact results in excessive bearing temperature. High temperatures result in discoloration of the races and the roller. In mild cases, the discoloration is from the lubricant staining the bearing surfaces. In severe cases, the metal is discolored from high heat.
Can an electric motor seize?
If seized up, a motor draws a heavy current. It is designed to do so momentarily as it starts, but if prevented from turning it may overheat and damage the insulation, and in the worst case, burn out the windings.
What is called when the bearing failed due to surface fatigue failure?
First, the subsurface-originated fatigue failure is also known as spalling fatigue. This subsurface rolling contact fatigue failure mechanism is the dominant failure mode for very smooth finish bearing surfaces and bearing materials with small, nonmetallic inclusions.
What causes the majority of motor failures in industrial applications?
Bearing failures account for the majority (50% to 65%) of all motor failures in industrial applications [6]. In the past few years with the wide use of PWM inverter drives, motor bear- ing failures have increased. The root cause of these failures is shaft-to-ground currents passing through the bearings.
What causes the bearings on a wheel to fail?
Even when bearings are being used under ideal conditions, failures of bearings are caused by deterioration of the material due to rolling fatigue.
What happens if a motor is transported without a rotor shaft?
Motors that are transported without the rotor shaft held securely in place can be subjected to vibrations within the bearing clearance that could damage the bearings. Similarly, if a motor is at a standstill and subjected to external vibrations over a period of time, the bearings can also become damaged.
What kind of bearings are used for non drive?
To prevent damage from electric current passage, an electrically insulated bearing at the non-drive end is usually used. There are two types of insulated bearings available from SKF: INSOCOAT bearings and hybrid bearings.