DC Motors and Generators
DC Motors and Generators
With the advent of low-cost AC drives, many motor repair facilities have lost expertise repairing DC motors and generators. With our strong ties to a wide variety of industries, we have maintained that expertise and have honed our repair and maintenance services for these units. We have extensive experience working with all manner of DC machines and providing valuable solutions to your problems.
Repair
In addition to our technical expertise, our well-equipped facilities allow us to tackle your motor repair from start to finish. We have a large fleet of vehicles, which allow us to move your motors safely. Our facilities are equipped with numerous overhead cranes (up to 35 tons) to facilitate the safe movement of your motor and components through the repair process. Upon arrival at our facility, the motor will be assigned a unique job number and a job file will be created. The entire repair process will be documented with high-resolution digital photographs. The unit will be disassembled, steam cleaned and bake dried in one of our bake ovens. Following the drying process, the motor will undergo a series of inspection tests to evaluate the root cause of the failure. Our technicians perform all necessary measurements with calibrated instruments to evaluate the condition of the bearing journals, end bells, armature and other mechanical components. We then perform a series of electrical tests on the armature, field coils, and interpoles. They are subject to insulation resistance (megger), bar to bar, AC field drop and other motor circuit evaluation tests with calibrated equipment as necessary to diagnose the condition of your motor. The inspection will culminate in a detailed quotation and scope of work.
Armature and Commutator
Once approved, our team will quickly and precisely repair and restore the condition of your DC motor. Our in-house machine shop will restore critical dimensions to within specification. Our service also includes the restoration or replacement of your commutator. From turning and undercutting (T&U) to replacement and expert advice regarding prolonging the life of your brushes, we have the expertise. If necessary, our winding department will rewind or repair your armature, field and interpole coils. Speaking of winding, our winders average experience is in excess of 20 years and that includes tons of DC work! In the event of an armature rewind, we will check the stripped armature with a core loss test to verify the integrity of the iron; if this shows a problem, we can repair or remanufacture the armature. To help promote the lowest life-cycle cost, we always use the highest quality wire for windings and the insulation we apply is designed to meet or exceed the requirements of class H insulating systems. Depending on your preference, varnish can be applied to the armature and coils in one of our dip tanks or processed in one of three vacuum impregnation systems (VPI).
Final Test
All rotating components will be precision balanced (up to 25,000 lbs) on one of our calibrated balance stands. Our expert technicians will assemble your motor; we use new premium bearings on every repair. The fully assembled motor will be subject to a final test run that can include load testing to 1000 horsepower. During the test run, we will collect bearing temperature and vibration data. This process validates the entire repair process and includes bearing temperature monitoring and vibration analysis. Prior to shipment, the motor is painted and our shop supervisor performs a final quality audit to ensure your motor is ready to go. As you should expect, all of the data collected during the repair process can be available to you in the form of customized reports that will provide your organization with a full understanding of the failure of the motor and the efforts undertaken to restore it to function.
Field Service
At your facility, our service capabilities include troubleshooting, preventative maintenance, brush and rigging cleaning, removal, installation and alignment services. Our teams of technicians are ready and available to assist you with the entire life cycle management of your motors. Our stores of spare parts, manufacturing capabilities and buyers ensure that replacement components are always available.
Solutions
At every step of the service process, from the initial phone call through the delivery of our detailed report, you will find our knowledgeable associates ready to provide you with valuable solutions to your DC maintenance requirements.