Electric motors are one of many man-made inventions that have revolutionised our way of life since their inception. With their wide range of applications both in everyday life and industrial settings, motors are now known to be fundamental to the modern world we live in today.
However, like any other manufactured object, these electric motors are vulnerable to breaking down. Whether it’s because of external causes, improper handling and usage, or any other reason, there’s a possibility of occasional failure and the need for servicing. When that time comes, operation managers have to make a critical decision: either rewind, or replace the motor completely.
Below, we briefly cover the details, pros, and cons for each course of action and the crucial questions to ask before committing to a decision:
Motor trouble: To rewind or replace
Electric motor rewinds are a well-known procedure that essentially strips off the old winding and replaces it with new ones, followed by a final insulation process. After a rewind following good practices, the motor’s lifespan is effectively extended, and its efficiency even increases in the process. The cost of rewinding can be as low as 40% compared to a total replacement, but it is not a viable option if one or more critical components, such as a stator core, are damaged beyond repair.
On the other hand, a replacement is relatively straightforward: switching an old motor unit for a newer one. Given that this process is far from instantaneous, it can be costly in terms of upfront costs and losses from operational downtime. However, if the investment is worth the price or wholly necessary, managers can expect better efficiency and lower operating costs from the new motor, recuperating the expenses in the long run.
Key questions to ask before deciding
Now that we have established what can be expected from rewinding and replacing a motor, let us go over the actual questions before deciding.
1. Is the motor still suitable for its purpose?
Operational needs will always change over time. In conjunction with the sustained damage, it is vital to inspect the motor’s duty cycles and processes and determine if it is still suitable to meet its requirements.
2. What is the condition of its stator core and rotor?
As mentioned briefly before, rewinding is only possible if the essential components of the motor remain uncompromised, specifically the stator core and its laminations and the rotor.
If these parts have sustained heavy damage, a complete replacement may almost always be preferable since repairs can be far too costly. But apart from costs, it is also recommended to consider lead times as well. If the lead time for replacement is not agreeable to the operation’s requirements, then repairs may be the better option.
3. Are there any other mechanical parts that have been damaged?
Besides the critical components, other motor parts must also be considered and evaluated when deciding on the course of action.
In a failure scenario, elements such as the bearing housing, shaft, and frame can also be subjected to damage. Therefore, examine their severity (or if there are any at all) and see if they can be easily replaced or repaired as well.
The golden question for any vital machinery, from electric motors to generators, will always be: to rewind or replace, or even to upgrade?
Hence, the bottom line here is to understand which benefits your equipment and business most (whether that be an electric motor rewind or a generator overhaul), and to discover the solution that will get the best out of the investment made in both time and money.