In any mechanical repair, the ability to properly disassemble, repair and reassemble the engine without unnecessarily damaging any parts is critical. This sounds simple. However, too many costly mistakes are made during the disarming process if all engines come in “like new”. The task would be simpler, although this would not guarantee proper engine mounting.
When a service centre is paid to repair equipment, they want it to stay in working order because if the equipment fails within the warranty period, they will have to bear the cost of repairing it again. So it makes sense to get the repair right the first time.
Repair procedures, as well as the engines themselves, are affected by changes in technology. In many cases, traditional repair methods may still be the most practical alternative. The options presented throughout this book are intended to help technicians select the correct repair method, recognizing that the final decision rests with the equipment owner.
Sometimes repair methods fall out of favour, not because better ways appear, but because of poor techniques. Other repair methods are suitable for some applications but not for others. The repairman's job is to decide the best method for each case.
This work is divided into sections for basic engine components, with repair methods and tips scattered throughout. Where practical, causes of failure are also discussed. This will help technicians select the most appropriate repair method for each application. The information presented is based on publications, technical journals, and literature supplied by an electric motor repair shop near me.
Important tools for the maintenance of electric motors
All industries have electric motors within their operation, so it is essential to have key tools that allow them to attend to most repairs that this equipment needs. Denver Electric Motor Repair is going to name three of these tools that should be considered in your budget anyway:
- Fast and safe bearing disassembly
You may be investing excessive time in the disassembly of electric motor bearings, and you are not aware of it because you have never proven the time that you can save with a correct extractor and especially everything if it is hydraulic. It has a hydraulic kit for extracting bearings that will greatly help with maintenance tasks. The TMBH 110E is of great help:
- Mounting of quality bearings
Most electric motor repairs are related to bearing replacement, which implies prioritizing an assembly tool. Depending on the adjustment, you can use a cold mounting kit such as the TMFT 36, which is a kit of quite an accessible price. However, with a little more investment, they can acquire an induction heater that allows us to intervene in motors of different sizes.
- Nothing will last without correct lubrication
After the change of bearings, lubrication is one of the last steps for the maintenance of electric motors. This step must be given due importance since the correct functioning of the motor depends on this operation. After mounting, electric motor repair is best so that the bearing receives a grease-free of impurities, which can be achieved with a direct application with the LAGP 400 tool.
When to repair or replace an electric motor?
When an electric motor fails, the decision to repair or replace it goes through a series of considerations that they analyze below. When evaluating whether to repair or outright replace a failed electric motor, it should first be taken into account that, in general, there are three types of electric motors:
- i) General Purpose, which manufacturers keep in stock and can be delivered immediately, even offering quick modifications to add certain accessories.
- ii) Those used by Original Equipment Manufacturers (OEM) and that have a special design are generally protected.
iii) Those of Special Manufacture, tailored to the application, are not kept in stock and have long delivery times.
Laminated Core Analysis
Assuming the engine is repairable, the baseline analysis (or initial cost approach) is to repair the engine to its original specifications. One of the most used considerations is the repair cost; as a general rule, it is said that when the repair exceeds 65-70% of the new higher efficiency motor, it is suggested to fit a new one.
However, the decision is not only about the repair cost; there are other factors. For example, the impact on efficiency. It should be considered that heat is used in the repair process to soften the windings for stator removal. The use of a controlled temperature will avoid possible damage to the interlaminar insulation of the iron core so that there is no increase in magnetic losses.
Therefore, it is recommended to test the laminated core before following a rewinding process, as indicated by electric motor repair denver co. These tests are known as the Core Loss Test, which establishes the maximum recommended loss level in W/kg; if this level is exceeded, it is suggested not to repair the engine and proceed with the change. But, if the motor is not in stock, nor is there a spare functional part, it must be repaired.
