Magnetic Degaussing: Why it is Critical for Electric Motor Repair?

Among the additional measures we are able to do at HECO when performing maintenance, maintenance, or maybe rebuilds on the electric motors of yours is magnetic degaussing. While some could think this move is not needed, experience has taught us it is able to help extend the lifetime of the bearings of yours and the engine of yours!
Why Magnetic Degaussing of Motor Components is Important

You will be asking yourself why magnetism is a problem — are motors exactly about currents and electromagnetism? It is real that AC electric motors experience magnetic induction via an electromagnetic field in the motor windings. Nevertheless, we are speaking about an alternative kind of magnetism: one which can damage the motor of yours rather than make it turn.

The kind of magnetism that’s a supply of concern will be, for instance, putting a metal screwdriver contrary to the conclusion of the motor shaft and getting it stay in place whenever you remove the hands of yours. That’s the type of magnetism which causes problems. Much more particularly, magnetized components parts are able to lead to bearings which seem to are put through shaft circulating currents and/or static discharge — and these may lead to severe harm to motor bearings.

We make use of a degausser machine to determine the magnetic level of the different components within the electricity motor of yours. We then shoot those values in gauss units. For reference, a regular refrigerator magnet measures at approximately hundred gauss while an important electromagnet (like you will see in an MRI machine) might be around 15,000 gauss.

The unique gauss values are subsequently mapped out on a diagram which shows the primary key ingredients in the motor of yours out to record what we discovered and also help decide whether any parts need degaussing (i.e., demagnetized). If a portion is above a particular gauss level, next we suggest degaussing.

The degaussing is achieved by switching to a demagnetizing unit. If, for instance, the component which has be degaussed is a shaft, cables from the demagnetizing device is going to be wrapped around the shaft. The demagnetizing unit is going to perform what’s known as a downcycle, which utilizes full wave DC to clear away any residual magnetism that’s present. Subsequently the car degauss is going to reverse polarity to gradually lessen the magnetic field. Whenever the procedures are done, the portion is checked once again utilizing the Gauss meter to make certain the magnetism level is appropriate.
What goes on When Magnetic Degaussing Is not Performed

When degaussing is not done, you run the risk of harm to the bearings of yours. Shaft circulating currents are able to discharge and cause electric damage on the surface of bearings. This particular harm takes the form of fluting, ball bearings with a frosted look because of area damage, along with electric pitting brought on by welding of 2 surfaces together. And it just takes a tiny quantity of magnetism to result in these sorts of issues.

This particular surface damage to bearings are going to accelerate the organic wear of theirs, which implies you will need to change them more frequently — and which can get costly. Damaged bearings will negatively affect motor performance and result in a catastrophic failure. Based on where and how all those damaged bearings are, they are able to damage various other moving parts inside the electricity motor of yours.