On the limited accuracy of balancing the axial fan impeller by automatic ball balancers

Authors

DOI:

https://doi.org/10.15587/1729-4061.2018.123025

Keywords:

axial fan, automatic ball balancer, automatic balancing, static balancing, dynamic balancing, transients

Abstract

The study explores the process of dynamic balancing of the impeller of an axial fan VО 06-300 (Ukraine) by two automatic ball balancers.

The computer simulation of the dynamics of the fan in the absence and presence of automatic balancers has confirmed the qualitative results of a previously conducted field full-scale experiment. Thus, the presence of automatic balancers reduces the following:

– the mean square value of the vibration velocity in the segment from the rotor start to the beginning of automatic balancing,

– the vibration velocity values at two resonant peaks when the rotor is running down, and

– the peaks of the vibration velocities in the section of the start of automatic balancing (74 times in the 3D modelling; 5.4 times in the field experiment).

The computer simulation of the dynamics of the axial fan with the «on» and «off» gravity forces has allowed determining the following:

– the effect of gravity on the accuracy of balancing the impeller decreases rapidly with increasing the cruising speed of the impeller,

– when increasing the forces of viscous resistance to the motion of the balls, the effect of gravity on the accuracy of the rotor balancing increases;

– at low speeds of rotation (15 r/s), the impeller can be balanced not better than by accuracy class G 2.5, but at the rated speed of 25 r/s, it is balanced according to accuracy class G 1.

Herewith, the residual vibration velocities that are caused only by gravity decrease with increasing the rotor speed.

The residual vibration velocities that are caused only by the eccentricities of the raceways increase directly proportionally to the rotor speed. Therefore, fast-turning rotors need a more precise installation of automatic balancers. It is recommended to reduce the eccentricity of the raceway of the automatic balancer at least 2.5 times in relation to the maximum permissible value.

Residual vibration velocities in the automatic balancing mode (up to 3 mm/s) on the test fan are mostly caused by gravity. The probable causes of residual vibration velocities are eccentricities of the raceways of the automatic balancers, standstill of the balls (lack of reaction to small unbalances), etc. Therefore, residual vibration velocities can be reduced at the stages of manufacturing and installing automatic balancers into a fan.

Author Biographies

Lubov Olijnichenko, Central Ukrainian National Technical University Universytetskyi ave., 8, Kropivnitskiy, Ukraine, 25006

Engineer

Department of Materials Science and Foundry

Vasil Hruban, Mykolayiv National Agrarian University Georgiya Gongadze str., 9, Mykolayiv, Ukraine, 54020

PhD, Assistant

Department of tractors and agricultural machinery, operating and maintenance

Mihail Lichuk, Central Ukrainian National Technical University Universytetskyi ave., 8, Kropivnitskiy, Ukraine, 25006

PhD, Associate Professor

Department of Mathematics and Physics

Vladimir Pirogov, Central Ukrainian National Technical University Universytetskyi ave., 8, Kropivnitskiy, Ukraine, 25006

PhD, Senior Lecturer

Department of Machine Parts and Applied Mechanics

References

  1. Polyakov, V., Skvortsov, L. (1990). Pumps and Fans. Мoscow: Stroyizdat, 336.
  2. Ziborov, K., Vanga, G., Marenko, V. (2013). Imbalance As A Major Factor Influencing The Work Rotors Mine Main Fan. Modern engineering. Science and education, 3, 734–740. Available at: http://mmese-2017.spbstu.ru/mese/2013/734_740.pdf
  3. Korneev, N., Polyakova, E. (2014). Aerodynamic disbalance of the turbocompressor as the reason of lowering of power indexes of internal combustion engines. Machine Builder, 1, 51–57.
  4. Yatsun, V., Filimonikhin, G. (2008). Experimental study of the efficiency of equilibration of impellers of axial fans by passive auto-balancers. Konstruyuvannya, vyrobnytstvo ta eksplyatatsiya silskohospodarskykh mashyn, 38, 100–105.
  5. Filimonikhin G., Yatsun, V. (2008). Chyslove modeliuvannia protsesu zrivnovazhennia kulovymy avtobalansyramy krylchatky osovoho ventyliatora [Numerical modeling of the balancing process by ball-type auto-balancers of an axial fan impeller]. Naukovyi visnyk natsionalnoho hirnychoho universytetu, 10, 72–77.
  6. Olijnichenko, L., Filimonikhin, G. (2014). Optimization of parameters of autobalancers for dynamic balancing of impeller of axial fans by 3D modeling. Eastern-European Journal of Enterprise Technologies, 6 (7 (72)), 12–17. doi: 10.15587/1729-4061.2014.30498
  7. Olijnichenko, L., Goncharov, V., Sidei, V., Horpynchenko, O. (2017). Experimental study of the process of the static and dynamic balancing of the axial fan impeller by ball auto-balancers. Eastern-European Journal of Enterprise Technologies, 2 (1 (86)), 42–50. doi: 10.15587/1729-4061.2017.96374
  8. Goncharov, V., Filimonikhin, G., Nevdakha, A., Pirogov, V. (2017). An increase of the balancing capacity of ball or roller-type auto-balancers with reduction of time of achieving auto-balancing. Eastern-European Journal of Enterprise Technologies, 1 (7 (85)), 15–24. doi: 10.15587/1729-4061.2017.92834
  9. Chung, J. (2005). Effect of gravity and angular velocity on an automatic ball balancer. Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science, 219 (1), 43–51. doi: 10.1243/095440605x8333
  10. Chan, T. C., Sung, C. K., Chao, P. C. P. (2012). Friction effect on ball positioning of an automatic balancer in optical disk drives. Microsystem Technologies, 18 (9-10), 1343–1351. doi: 10.1007/s00542-012-1540-y
  11. Bykov, V. G., Kovachev, A. S. (2014). Dynamics of a rotor with an eccentric ball auto-balancing device. Vestnik St. Petersburg University: Mathematics, 47 (4), 173–180. doi: 10.3103/s1063454114040037
  12. Sung, C. K., Chan, T. C., Chao, C. P., Lu, C. H. (2013). Influence of external excitations on ball positioning of an automatic balancer. Mechanism and Machine Theory, 69, 115–126. doi: 10.1016/j.mechmachtheory.2013.05.009
  13. Chang, K.-H. (2008). Motion Simulation and Mechanism Design with COSMOSMotion 2007. Norman, Oklahoma, Paperback: Schroff Development Corporation, 142.

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Published

2018-02-07

How to Cite

Olijnichenko, L., Hruban, V., Lichuk, M., & Pirogov, V. (2018). On the limited accuracy of balancing the axial fan impeller by automatic ball balancers. Eastern-European Journal of Enterprise Technologies, 1(1 (91), 27–35. https://doi.org/10.15587/1729-4061.2018.123025

Issue

Section

Engineering technological systems