Workshop «Shaft alignment and dynamic balancing»
We invite technical specialists to participate in the training course on the topic «Shaft alignment and dynamic balancing» which will take place on 12-13 September, 2019 in Germany (Lubeck). The workshop is arranged for specialists in quality, service engineers, mechanics and power engineers who are responsible for the reliability of machines and industrial equipment.

Kronsforder Allee 45,
23560 Lübeck
Tel: +49 (0) 451-370-87-700
Articles -- Dynamic balancing

Fan balancing

Ventilation is an air regulating system. The main element of the system is a fan.The fan is a device for producing a current of air or other gases or vapours. Why does the industry need the fans and why is it so important to take care of the fan health?

Air quality influences the human being. Air pollution can cause various diseases and seriously affect productivity. A lot of dangerous gases are produced in the course of the production processes, therefore the ventilation of the industrial premises is very important. Today there are many different kinds of fans, the main ones: axial, centrifugal, radial, tube axial fan, tangential and exhaust fans. All of them can experience an unbalance. The unbalance is the most dangerous disease, as it is shown in the low-frequency spectrum and the most damaging to the bearings and seals.The fan wheel unbalance occurs due to natural deterioration, which may be enhanced by the presence of solid particles in the pumped air, as well as the adhesion of various materials to the impeller. To avoid the structural damage and severe consequences it is necessary to control the overall vibration level and the vibration at the rotor rotation frequency, and to perform the balancing in case of the increase of the rotational frequency component.

The unbalance correction can be performed by means of dynamic or static balancing using the balancing machines or portable device BALTECH VP-3470. The static balancing of the fan wheel can be performed without the dismounting, while the fan balancing on the balancing machine requires the wheel dismantling, which is not always possible because of the rotor large dimensions or design features. This process is very expensive and time-consuming. Therefore BALTECH recommends using the VibroPoint Series BALTECH VP-3470 portable system for fast and efficient dynamic balancing of the fans in field.

The balancing procedure is implemented in the BALTECH VP-3470 step-by-step: first measure the initial phase and vibration level (initial vibration), then install the test weight (test weight- clamp), measure the phase and vibration again. Then the electronic unit calculates the amount and installation angle of the correction mass. As opposed to analogue system, BALTECH VP-3470 has additional functions to make the balancing procedure even easier. For example, BALTECH VP-3470 calculates the test mass amount on condition that the test mass will be left on the rotor.

Because not every fan has a special balancing plane for installation of the correction masses, the test mass is welded to the impeller blades, which in its turn complicates the dismantling. BALTECH VP-3470 allows placing the correction mass in the direction of rotation or against the rotation direction for the ease of operation. The two- channel vibration analyzer with the balancing function makes it possible to reduce the vibration level at the rotation frequency by 3-10 times.

Use of the balancing system BALTECH VP-3470 doesn’t require special operating skills, it’s enough to understand general balancing principles and conditions limiting its effectiveness. If the operator has never performed the balancing before, we recommend him to visit our seminar Reliability technologies at the Baltech training centre.