DC motor maintenance

It is American-made DC motor.
 Insulation improvement repair for the failure.
Since this type of removable is stator coil, it is easy rewinding.
When poured into the varnish to the rotor coil, because the center of rotation is eccentric,
There is a need to take a dynamic balance again.

55 kw 6 pole motor burnout and rewinding

 55kw 6p motor coil rewinding after the case of the rotor also cleaned, also exchange bearings.

110 Kw 2 Phase Motor Burntout and Rewinding

Rewinding a low voltage generator 225 KVA, 14 pol., 400 V

Spraying metal powder. Edit Required Shaft dimension

High Voltage Motor rewinding "ELIN" 6.2 KV 2 separate windings: 1.485 and 985 rpm / min, 900 per 245 KW

Neuwicklung Generator, 800 KVA, 5,2 KV, 750 rpm / min

5000hp Motor Rewinding

Crusher Motor At Workshop

 Cone crushers are usually run on belt drives driven by an electric motor or diesel engine.

300hp Baldor Motor At Workshop

How to make a Frame 5 generator ‘new’ in 15 easy steps

Posted on November 19, 2012 by Team CCJ

Your Frame 5 generator may be a classic—between 20 and 40 years old—perhaps even an antique (over 40). Physical age doesn’t matter much in most cases because these machines were designed conservatively, constructed with craftsmanship, and built to last. How long it pays to keep Frame 5s older than about 25 years in service continues to be a question on the minds of asset owners. Many had been content with just letting these workhorses run down to retirement. But that was before their value increased as ancillary-services providers for regional grids challenged to maintain system stability in the new era of must-take renewables.
Maintaining your unit in top condition begins with proper operation. During turbine overhauls, conduct routine electrical, mechanical, and NDE assessments and perform all associated generator maintenance. Take advantage of today’s upgrades when the economic equation points in that direction; extend your vintage Frame 5 generator’s life and possibly increase its capacity. With such enhancements, your classic will gain value and stand the test of time.
Here, engineers from TurboCare, which overhauls many Frame 5 generators each year at its shops worldwide, walk you through the key steps involved in rehabilitating a vintage machine to virtually as-new condition.

	1. Classic Frame 5 generators typically arrive at the shop in poor condition. Mechanical, electrical, thermal, and environmental aging influences have taken their toll. Stator and rotor winding insulation systems usually are obsolete. Plus, retaining rings, collector rings, core iron, and the end-basket support system are dated and should be upgraded.
	2. A classic commonly contains asphalt-mica stator windings. The straight-section outer binder, strand insulation, and/or end connection putty may contain asbestos; test prior to demolition. If positive, use only trained abatement specialists.  As the stator windings are extracted, critical dimensions are taken for the engineering and redesign process.
	3. Once stripped of the original windings, the stator housing and core iron are grit-blasted clean. Great care is required during this operation, because the stator laminations are susceptible to “smear” damage. Perform a near-flux core loop test to requalify the iron for reuse.
	4. A full core replacement can be performed with either stamped punchings or laser-cut laminations. The lamination steel used should be either grade M6, Cold-Rolled Grain-Oriented (CRGO), or M15, Cold-Rolled Non-Grain-Oriented (CRNGO), with C5 core plating as the interlaminar insulation.
	5. The original two-turn full diamond coils are upgraded to two-turn, 360-deg Roebel half-coils, which are far superior to the original windings in many ways, including these: They have more copper (lower I2R losses), more conductors in-hand (lower eddy-current losses), and a Roebel transposition (lower circulating-current losses), as well as a  modern resin-rich mica thermosetting insulation system.
	6. The new and improved windings are installed into the stator core iron together with the following upgrades: End-basket support system, vertical slot fillers, side packing, stator slot wedge system, encapsulated end connections, circuit ring bus, new RTDs, new heaters, a flux probe, and partial-discharge monitoring system.
	7. A comprehensive acceptance program is conducted following a stator-winding upgrade and includes successful completion of an El CID core test, wedge-tightness mapping, insulation resistance, Polarization Index; controlled over-voltage; ac and dc high potential, power factor and tip-up, and phase resistance.
	8. The rotor is dismantled down to a bare forging, taking steps to avoid the release of asbestos-bearing materials, if present. Copper samples are removed from the main field winding and lab-tested for composition, tensile strength, hardness, and yield strength. Main field windings generally are suitable for reuse.
	9. Rotor components—such as the rotor body forging, retaining rings, blower hubs, and rotor body wedges—are cleaned down to grey metal. Each individual part is subjected to requalifying nondestructive testing, which may include dye-penetrant, ultrasonic, eddy-current, and magnetic- particle examinations. Non-conforming parts are either repaired or replaced.
	10. The reconditioned and requalified main field coils are wound back into the rotor-body forging. The latest turn-to-turn and ground-wall insulation systems are incorporated into the process. Slip-planes, critical to unimpeded axial thermal expansion and contraction of the windings, are designed into the upgraded main field winding system.
	11. Specially designed and fabricated slot and end-winding compression fixtures are installed on the newly installed coils, forming a symmetrically round and dimensionally concentric main field winding. The rotor is then induction-cured, to set and stabilize the associated adhesives while seasoning the windings.
	12. All new top creepage blocking is installed along with the rotor body wedges and a new permanent end blocking system. Should resin-load materials be used, the end windings are compressed once again, and the rotor windings are subjected to a second and final induction curing process.
	13. The rewound, reassembled, and fully upgraded rotor is placed in the high-speed balance facility. There it is balanced to operational speed, subjected to a minimum 10% over-speed run, and at-speed electrical testing—including insulation resistance, ac impedance, RSO and/or flux probe.
	14. The generator rotor now is completely upgraded, uprated, and “zero houred.” With all new turn-to-turn, ground wall, and retaining-ring insulation systems, modern 18Cr18Mn retaining rings, and new collector rings, the classic Frame 5 rotor is better than when it was new and ready to begin its second life cycle.
	15. The Frame 5 generator is a true classic in every sense of the word: simple in design, rugged in construction, and easily acceptant of modern upgrades and uprates. Rebuilding of vintage machines typically makes better economic and business sense than buying new. Owners can expect years of relatively maintenance-free service. source:http://www.ccj-online.com/how-to-make-a-frame-5-generator-new-in-15-easy-steps/

This rotor end ring was not properly brazed to the bars, resulting in a complete open circuit failure.

A random wound stator damaged by contact with the rotor.

Reinsulation of 18.8 MW Generator

 coil-strip

completed coil-fitted to rotor

completed-coil

 pole coil heated and pressed

450 HP motor winding repair

SR4 GENERATOR MAINTENANCE 1000 KW.

achievement cap be removed with the extractor, we discover that the bearing was not installed right, is an open ball box for lubrication . this generator, modern as it is, comes with sealed bearings lubricated for life, and no lubrication  enabled. the overheated bearing was installed, with wear and about to fail .
Technical recommendation: when a generator is Travado bearing at the top and the same extractors remove it fail, never resort to the method of the hammer, this could only twist the shaft or crack the lid. appropriate solution is the force controlled hydraulic puller.

Repair of electric city transport

Most often, electric urban transport are traction and support . This is because these types motors are widely used is in the transport industry.
A wide variety of options and models of traction and auxiliary engines for different types of transport, makes repairs traction motors - an interesting and challenging enough for experts. Our masters are not afraid of challenges - they are a force to repair the traction motors of urban transport of any complexity. The specialists of our company at the highest level of quality collector carry out repair of electric motors, the rotor of the motor repair , repair of motor windings and other engine modifications produced on the territory of the Russian Federation and abroad. In addition to repairs , we can provide our clients and this service as fast commutator motors .

Among the reasons for the vehicle of a particular model is faulty great multitude, so repair and traction motors and engines of other models can be very, very different , both in complexity and execution time , and on the need for special equipment and optional accessories or parts . What would have been the cause of the engine malfunction of your car, our specialists will make such work as the repair of electric motors and traction collector , repair of the rotor of the motor , repair of electric motors and windings of the other elements , as well as fast commutator motors , as soon as possible , with providing an excellent quality of work done . At all stages of cooperation, we try to provide the best conditions for our customers. We respect our customers and do not spend their time in vain , because in modern life being appreciated very much. We save our clients' time , and , therefore, does not help to lose the financial benefit from the use of the vehicle. It is therefore, urgent repair of traction motors and engines other variations in our company - one of the priorities .

Efficiency in the work of our specialists - the result of a responsible approach to any process with all the necessary parts and equipment used in processes such as the repair of electric motors and traction collector , repair of motor rotor , and other items , including repair of motor windings and rewind commutator motors . In the warehouses of our company in the constant presence of a large number of spare parts and accessories for all types of repairs . All components and parts used in our work, only from trusted manufacturers with an excellent reputation and popularity among professionals. 

 

Generator Maintenance

This generator had sulphation (by proximity to the sea), also baristores block burst. Was undertaken generator maintenance, triple layer was applied coating, joint replacement and bearing rectification.

The generator is practice a recalibration of valves and injection system tuning. Note, that the adjustment of valves for admission was 0.015, and 0.030 for escape. The injection timing of this engine should be 86.80 mm, and was 87.20mm. this advancement in injection time, caused unwanted sounds in the engine, so as to absorb the load problems. With the proper injection time adjustment, the engine sounds good, and its performance is much better than before.

Repair of induction motors

Induction motors are among the most common types of electric machines . Because of the simplicity of the device , high reliability, good performance and relatively low cost , represented by electric motors are used in all sectors of the economy : construction, industry, agriculture , transport , etc. However, as with any electrical machines, they tend to break and require periodic maintenance.

 Repair induction motors produce highly professional and skilled craftsmen , given all the necessary requirements and respecting quality standards . To perform the repair of any motor model , you need to begin to determine the amount of repair work by evaluating the nature of his faults. The most common failures of electric motors are: overload or overheating of the stator circuit between turns , various types of damage to the bearings , windings, stator , etc.
Current and capital repairs - are two main types of repair work with electric motors . Thanks to the current repair is possible to maintain the durability and reliability of the motor .
Overhaul requires more complex types of work aimed at making technical characteristics are refurbished machines were not inferior to the latest models of cars.

Typically , the reason for the failure of this item is in violation of the overall condition of the windings , so it becomes necessary rewind induction motor. Failure causes the motor windings can be different: from overheating working parts to large engine life . Thus, the engine malfunction , causing an urgent need to repair induction motors , is always manifested in different ways. Before performing repairs to motors , our experts will make a detailed diagnosis of all the elements and reveal the fault. Determine the reasons for what it needs repair induction motors , will try to identify how much whether to rewind the induction motor and find other reasons for which the device could be damaged.
Repair induction motors may be necessary when a decision of both mechanical and electrical problems . Before the repair work with induction motors (fast asynchronous motor) , the master of our company can significantly reduce the time required for the repair of electric motors , increasing the quality of the work.