Inspection, maintenance and repair of electrical machinery

Maintenance, testing and repair of­ electrical machines

Vendor-independent repairs and expert advice

Our technicians are equipped to repair not only drive equipment of all brands, constructions and types (up to 10 kV; 7.5 MW; 25 t), but also pumps, welding machines, electromagnets and other electrical equipment, irrespective of the manufacturer. Whether it’s cleaning, rewinding, balancing, re-bearing , or painting, our goal is always the same – to return your machinery to you in a state as close to new as possible.

We also advise in matters regarding drive technology, for instance with respect to new plants, refits or modernisations, and tell you how to save energy by employing controlled drives.

Major repair work is performed in our repair workshops, which are equipped with the latest technology, including a pyrolysis oven, vacuum impregnation systems, computer-controlled balancing benches, the latest test bays, and 25-tonne crane systems. We employ only the latest measuring equipment and techniques. Naturally, we also provide you with full documentation of all work performed. All important procedural steps are documented by process logger.

We have a wide range of spare parts for electric motors from many different manufacturers in stock and also offer new motors on request. Even if parts are no longer available, we can often prolong the service life of your machinery considerably by building them especially for you.

Machinery types

  • Three-phase motors
  • High-voltage motors
  • DC machines
  • AC drives 

  • Transformers
  • Emergency generators
  • Pumps and equipment

State-of-the-art methods

Laser optical alignment

At least half of the mechanical damage to rotating machinery is caused by offset. The reaction forces of offset create additional vibrations, stress the bearing, produce frictional losses and wear out couplings. Systematic correction of a machine’s alignment requires regular checking of the geometric alignment status. Laser optical alignment measurement technology makes it easier for you to keep alignment problems under control. Better alignment means more efficient, reliable and longer-lasting rotating machinery.

Furthermore, a study has shown that if alignment is improved even by only a few 1/100 mm, which is very easily achieved with a laser alignment system, there will be an energy saving of at least .5 per cent.

Fast, precise machine alignment with a laser has replaced the traditional, established method with a straightedge and dial gauge. The laser not only determines the setting of the machine and coupling geometry but also measures the rotational axes.

How does laser optical measurement work?
Laser optical measuring instruments determine the extent of the offset by measuring the displacement of the shafts. The laser/detector unit (sensor) and the reflector are attached to either side of the coupling using infinitely adjustable clamping devices. The laser beam from the transmitter passes through the coupling and enters a glass prism in the reflector, from where it is reflected back and strikes a position detector in the sensor.

Rotating the shafts by 60°, once clockwise and once anti-clockwise, is generally sufficient to determine the alignment status of the coupling very precisely. The rotational axes are in alignment if, when the shafts are rotated, the point of impact of the laser beam remains radially constant on the surface of the detector. Deviations in the points of impact are recorded as parallel and angular offsets. The computer calculates the coupling values (parallel offset and gap) and correction values from the changes in the points of impact. The same principle is also used to observe the machine movements ‘online’ while the alignment is being corrected, via the display on the measuring instrument.

This measuring principle and the way it is carried out offer users many practical advantages. The variety of different measurement techniques make it possible to take almost every conceivable situation into account when aligning a machine. For example, it is not difficult to align non-coupled shafts precisely with the appropriate measurement function. Laser optical alignment is generally faster and costs less than traditional methods and produces more accurate results.


Poor alignment = high energy consumption!
The link between the alignment within a machine and its energy consumption was investigated in a study by ICI Chemicals in northern England, which made it possible to state the amount of energy that can be saved by proper machine alignment.

The unit at ICI on which the study was carried out consumes approximately 80 MW, 50 MW of which can be directly influenced by shaft alignment. It was discovered that an average shaft offset of 35/100mm can be assumed. The energy consumption in this alignment scenario increases by .8 per cent for jaw couplings and .5 per cent for boom couplings.

This shows that if alignment is improved even by only a few 1/100 mm, which is very easily achieved with a laser alignment system, there will be an energy saving of at least .5 per cent.

Our services in detail:

  • Determination of the condition the machinery is in
  • Measurement of coupling offset, coupling gap and machine tilt
  • Screen-guided correction of each anti-vibration mounting
  • Evaluate the recorded data
  • Advise the customer and decide together what measures to take
  • Implement measures, taking customer’s deadlines into account

Condition Monitoring

Condition monitoring, which involves regularly checking a machine’s status by measuring key parameters, is undertaken to improve safety and efficiency.

  1. Safety: An extremely reliable rapid-response safety system (emergency shut-off) can be created based on sensor data analysed in real time. Most of the current systems, including vibration sensors, are much less precise and do not contribute to explaining why and how damage occurs. Online condition monitoring makes it possible to shut off the machine based on the data that has been recorded, therefore also making it possible to analyse the factor that caused the disturbance.
  2. Machine efficiency: Monitoring the machine’s condition is the essential prerequisite for "condition-oriented maintenance", a new strategy that replaces the previously widely used “preventive” maintenance. Preventive maintenance involved shutting down a machine at regular intervals to check components and replace them if necessary and often resulted in intact components being exchanged, wasting their remaining useful life.

Condition monitoring places extreme demands on the sensors and measurement processing and requires in-depth knowledge of the equipment being monitored. However, it also offers the greatest potential cost savings, because critical machine elements are used virtually until the end of their service life and any maintenance can be scheduled to fit in with the production plan.

Condition-oriented monitoring is an interdisciplinary field drawing from mechanics, acoustics, system theory, electronics and informatics and has not yet been fully researched, though it is developing very rapidly. While it has already proved to be unerringly accurate in the monitoring of individual components, condition-oriented monitoring of complex machinery grows less precise as the number of signals originating from different places within a system rises. There has also been a lack of suitable sensors capable of picking up signals directly in the zones where the wear and tear and damage occur. Microsystems technology may provide the answer here in the future, for example by applying sensors in thin-film technology that can be applied directly to the structure to be monitored.

The challenges:

  • Finding suitable measuring points and sensors
  • Identifying parameters that provide more information (condition parameters) about damage to the relevant components
  • The targeted application of signal analysis and pattern recognition
  • Dealing with the enormous amount of data.

Putting it simply: what needs to be monitored, when, how and what with?
What condition monitoring can not do is to recognise and prevent spontaneous failures such as fatigue fractures in shafts. 

Vibration analysis

The best – and most cost-effective – way to ensure that equipment operates smoothly is to maintain or replace a component shortly before it fails. But how do you know when the right time has come? With many types of equipment, it is not possible to assess wear and tear, or even to measure it directly, because the worn parts are not accessible.

This is where indirect damage detection using regular measurement of the machine vibrations, followed by computer-supported evaluation, comes in. Measuring-systems of this type comprise fixed measuring points, a portable measurement sensor and a PC with special software.

Vibration analysis detects machine imbalance, machine offsets and bearing damage before damage occurs. Trend monitoring uses the shock pulse method to analyse high-frequency bearing vibrations. The results indicate the development of the characteristic condition parameters of the machine bearings.

Regular recording of these parameters makes it possible to detect bearing damage in the early stages and accurately assess the condition of the bearings. For example, it is possible to find out whether a bearing is adequately lubricated or is running dry. These advantages, together with its ease of use, have made the shock pulse method very popular in the maintenance world. Selected preventive measures, including alignment, balancing and changing the bearings make unexpected, uneconomic "first aid" measures a thing of the past.

Our services

Independent advice

We provide impartial advice, free of charge and with no obligation. Our partnerships with a large number of reputable manufacturers and our many years of experience enable us to develop solutions that are tailored precisely to your requirements.

Maintenance

We provide tailor-made, manufacturer-agnostic maintenance and immediately make any repairs that may be necessary.

Modernisation

We protect the value of your investments by modernising your electrical machinery.

Repairs

We generally keep a stock of the most important wearing parts. We can also provide professional engineering and repair services for more complex challenges by working with our other business divisions. Also, thanks to our many service centres, our technicians are never far away and can keep your electrical machinery running smoothly.

Testing

We examine and test your mobile electrical machinery in the intervals prescribed by DGUV 3 and other regulations. This includes preparing the necessary documentation for you.

Installation and dismantling

Our trained installers will professionally install and dismantle your electrical machinery following a modernisation or a similar project.

Commissioning

After your equipment has been shut down temporarily or newly installed, our skilled engineers and technicians will professionally commission your electrical machinery and monitor the start-up process.

Maintenance portal

Our maintenance portal is a full-featured documentation system for holding all your reports, manuals or other electrical machinery documents. With our system, you can store your documentation on certified servers, ensuring total regulatory compliance and reducing your liability while still having the freedom to plan inspections well in advance.

This system can be used for all the electrical machinery at your company, regardless of who conducts your inspections. That gives you the kind of complete, detailed maintenance, inspection and repair history that you need for preventive maintenance of all of your electrical machinery.

Preventative Maintenance

Because prevention beats downtime
Preventive maintenance is the secret to avoiding unplanned downtime. It allows you to do all your repairs and maintenance before breakdowns even happen. Sensors installed in industrial doors or electrical machinery regularly send status data that, once analysed, can help to identify and prevent impending equipment failures.

Customers can access the data in the Blumenbecker maintenance portal and analyse it from different perspectives at any time. If problems start to manifest themselves, appropriate action can be taken in time to prevent a breakdown or extended system downtime.
 

Condition monitoring of low-voltage motors
The ABB Ability™ Smart Sensor supplies data on vibration, temperature, overload and other operating and state parameters. The data is analysed with specially developed software in order to inform the plant operator’s maintenance planning. The solution helps to reduce downtime by as much as 70 percent, extend motor lifetimes by up to 30 percent and reduce energy consumption by up to 10 percent.

The ABB Ability™ Smart Sensor is mounted directly on the casings of low-voltage motors. No elaborate wiring is needed. It transfers information about the motor’s condition by smartphone to a secure cloud-based server.

Condition monitoring of industrial doors
We have partnered with Marantec to offer a sensor-based condition monitoring system for industrial doors. This solution lets you identify imminent problems in time and respond before the door fails.

Specialists also for Ex motors

When it comes to repairs, it is particularly important to have well-trained, experienced personnel. Due to their many years of experience, excellent training and professional development, our mechanics and service staff know almost everything there is to know about the maintenance, repair and assembly of electrical equipment. So you can be sure of top-quality servicing, performed by expert personnel.

We also have certified service personnel in-house for explosion-protected motors (Ex motors).

We service all models, irrespective of manufacturer – even outside normal business hours. You can contact us by phone any time, 24 hours a day. Our central warehouse stocks a wide range of spare parts for even the most extensive repairs. We can even obtain unusual spare parts within a short space of time.

If you have further questions, please feel free to contact us. Our electrical machinery repairs experts will be happy to answer them at any time.