, Volume 7, Issue 1, pp 59–73 | Cite as

Experimental rigs for testing components of advanced industrial applications

  • Enrico CiulliEmail author
Open Access
Research Article


This paper presents experimental rigs of the Research Centre for the Mechanics of Turbomachinery of the Department of Civil and Industrial Engineering of the University of Pisa. Most of them were designed and constructed to allow investigations of real machine components and to furnish more realistic results than basic tribological test rigs.

Tilting pad journal bearings, as well as gears and complete gearboxes for advanced industrial applications, can be tested using the rigs described in the paper. A novel test rig with a power rating of approximately 1 MW allows investigations of the static and dynamic characteristics of high-performance tilting pad journal bearings for turbomachinery. A twin disc machine and closed loop gear test rig are used to investigate the different kinds of wear mechanisms occurring in gears. Functional and durability tests on planetary gearboxes for new turbo-fan engines could be performed using another novel large test rig. A circulating power configuration was adopted for most of the rigs so that only the power needed to cover the friction losses has to be supplied, while the circulating power can be more than 20 times higher. All the test rigs include very complex load applications and lubrication plants, as well as dedicated control and data acquisition systems.

The rigs and related plants were designed and constructed through strong and fruitful collaborations between the university and some large and small–medium companies. Despite some limitations in the publication of the results as a result of the industrial sensitivity of the data, the synergy among these different actors was stimulating and fundamental for the realization of new advanced industrial applications.


experimental rigs tilting pad journal bearings twin disc machine gears gearboxes 



The author wishes to thank everyone at AM Testing, GE Oil & Gas, and GE Avio, along with those department colleagues that have collaborated in the realization of the laboratories and the complex experimental rigs and plants.

The research center was co-financed by the Region of Tuscany in the framework of the ATENE project and by the European Clean Sky platform.


  1. [1]
    Martins R C, Fernandes C M C G, Seabra J H O. Evaluation of bearing, gears and gearboxes performance with different wind turbine gear oils. Friction 3(4): 275–286 (2015)CrossRefGoogle Scholar
  2. [2]
    Li X M, Olofsson U. FZG Gear Efficiency and pin-on-disc frictional study of sintered and wrought steel gear materials. Tribol Lett 60: 9 (2015)CrossRefGoogle Scholar
  3. [3]
    Björling M, Miettinen J, Marklund P, Lehtovaara A, Larsson R. The correlation between gear contact friction and ball on disc friction measurements. Tribol Int 83: 114–119 (2015)CrossRefGoogle Scholar
  4. [4]
    Fernandes C M C G, Blazquez L, Sanesteban J, Martins R C, Seabra J H O. Energy efficiency tests in a full scale wind turbine gearbox. Tribol Int 101: 375–382 (2016)CrossRefGoogle Scholar
  5. [5]
    Ciulli E. Tribology research trends in Italy. Proc Inst Mech Eng Part J J Eng Tribol 223(8): 1091–1113 (2009)CrossRefGoogle Scholar
  6. [6]
    Sander D E, Allmaier H, Priebsch H H, Reich F M, Witt M, Füllenbach T, Skiadas A, Brouwer L, Schwarze H. Impact of high pressure and shear thinning on journal bearing friction. Tribol Int 81: 29–37 (2015)CrossRefGoogle Scholar
  7. [7]
    Sander D E, Allmaier H, Priebsch H H, Witt M, Skiadas A. Simulation of journal bearing friction in severe mixed lubrication–Validation and effect of surface smoothing due to running-in. Tribol Int 96: 173–183 (2016)CrossRefGoogle Scholar
  8. [8]
    Sander D E, Allmaier H, Priebsch H H, Reich F M, Witt M, Skiadas A, Knaus O. Edge loading and running-in wear in dynamically loaded journal bearings. Tribol Int 92: 395–403 (2015)CrossRefGoogle Scholar
  9. [9]
    Cristea A F, Bouyer J, Fillon M, Pascovici M D. Pressure and temperature field measurements of a lightly loaded circumferential groove journal bearing. Tribol Trans 54(5): 806–823 (2011)CrossRefGoogle Scholar
  10. [10]
    Litwin W, Dymarski C. Experimental research on waterlubricated marine stern tube bearings in conditions of improper lubrication and cooling causing rapid bush wear. Tribol Int 95: 449–455 (2016)CrossRefGoogle Scholar
  11. [11]
    Yamada H, Taura H, Kaneko S. Static characteristics of journal bearings with square dimples. J Tribol 139: 051703 (2017)CrossRefGoogle Scholar
  12. [12]
    Giraudeau C, Bouyer J, Fillon M, Hélène M, Beaurain J. Experimental study of the influence of scratches on the performance of a two-lobe journal bearing. Tribol Trans 60(5): 942–955 (2017)CrossRefGoogle Scholar
  13. [13]
    Dimond T, Younan A, Allaire P. A review of tilting pad bearing theory. Int J Rot Mach 2011: 908469 (2011)Google Scholar
  14. [14]
    Chasalevris A, Dohnal F. Vibration quenching in a large scale rotor-bearing system using journal bearings with variable geometry. J Sound Vib 333(7): 2087–2099 (2014)CrossRefGoogle Scholar
  15. [15]
    Chasalevris A, Dohnal F. A journal bearing with variable geometry for the suppression of vibrations in rotating shafts: simulation, design, construction and experiment. Mech Syst Signal Process 52–53: 506–528 (2015)CrossRefGoogle Scholar
  16. [16]
    Varela A C, Nielsen B B, Santos I F. Steady state characteristics of a tilting pad journal bearing with controllable lubrication: comparison between theoretical and experimental results. Tribol Int 58: 85–97 (2013)CrossRefGoogle Scholar
  17. [17]
    Salazar J G, Santos I F. Active tilting-pad journal bearings supporting flexible rotors: Part I–The hybrid lubrication. Tribol Int 107: 94–105 (2017)CrossRefGoogle Scholar
  18. [18]
    Salazar J G, Santos I F. Active tilting-pad journal bearings supporting flexible rotors: Part II–The model-based feedbackcontrolled lubrication. Tribol Int 107: 106–115 (2017)CrossRefGoogle Scholar
  19. [19]
    Dimond T W, Sheth P N, Allaire P E, He M. Identification methods and test results for tilting pad and fixed geometry journal bearing dynamic coefficients–A review. Shock Vib 16(1): 13–43 (2009)CrossRefGoogle Scholar
  20. [20]
    Childs D, Hale K. A test apparatus and facility to identify the rotordynamic coefficients of high-speed hydrostatic bearings. J Tribol 116(2): 337–343 (1994)CrossRefGoogle Scholar
  21. [21]
    Ha H C, Yang S H. Excitation frequency effects on the stiffness and damping coefficients of a five-pad tilting pad journal bearing. J Tribol 121(3): 517–522 (1999)CrossRefGoogle Scholar
  22. [22]
    Wygant K D, Flack R D, Barrett L E. Measured performance of tilting-pad journal bearings over a range of preloads–Part I: Static operating conditions. Tribol Trans 47(4): 576–584 (2004)CrossRefGoogle Scholar
  23. [23]
    Wygant K D, Flack R D, Barrett L E. Measured performance of tilting-pad journal bearings over a range of preloads–Part. II: Dynamic operating conditions. Tribol Trans 47(4): 585–593 (2004)CrossRefGoogle Scholar
  24. [24]
    Ikeda K, Hirano T, Yamashita T, Mikami M, Sakakida H. An experimental study of static and dynamic characteristics of a 580 mm (22.8 in.) Diameter direct lubrication tilting pad journal bearing. J Tribol 128(1): 146–154 (2006)CrossRefGoogle Scholar
  25. [25]
    Bang K B, Kim J H, Cho Y J. Comparison of power loss and pad temperature for leading edge groove tilting pad journal bearings and conventional tilting pad journal bearings. Tribol Int 43(8): 1287–1293 (2010)CrossRefGoogle Scholar
  26. [26]
    Delgado A, Vannini G, Ertas B, Drexel M, Naldi L. Identification and prediction of force coefficients in a five-pad and four-pad tilting pad bearing for load-on-pad and load-between-pad configurations. J Eng Gas Turbines Power 133(9): 092503 (2011)CrossRefGoogle Scholar
  27. [27]
    Shen J X, Xiong X, Li G P, Wang X J, Hua Z K, Nie Z. Experimental analysis of dynamic oil film pressure of tilting-pad journal bearings. Tribol Lett 63(3): 36 (2016)CrossRefGoogle Scholar
  28. [28]
    Dang P V, Chatterton S, Pennacchi P, Vania A. Effect of the load direction on non-nominal five-pad tilting-pad journal bearings. Tribol Int 98: 197–211 (2016)CrossRefGoogle Scholar
  29. [29]
    Ciulli E, Forte P, Maestrale F, Nuti M. Design of a test rig for the dynamic characterization of large size pad bearings. In Proceedings of the 44th Convegno Nazionale AIAS, Messina, Italy, 2015: 343–352. (In Italian)Google Scholar
  30. [30]
    Forte P, Ciulli E, Saba D. A novel test rig for the dynamic characterization of large size tilting pad journal bearings. J Phys Conf Ser 744(1): 012159 (2016)CrossRefGoogle Scholar
  31. [31]
    Delgado A, Librashi M, Vannini G. Dynamic characterization of tilting pad journal bearings from component and system level testing. In Proceedings of ASME Turbo Expo 2012: Turbine Technical Conference and Exposition, Copenhagen, Denmark, 2012: 1007–1016.Google Scholar
  32. [32]
    Hoehn B R, Oster P, Tobie T, Michaelis K. Test methods for gear lubricants. Goriva i Maziva 47(2): 129–152 (2008)Google Scholar
  33. [33]
    ISO 14635–1 Gear–FZG test procedures-Part 1: FZG test method A/8,3/90 for relative scuffing load-carrying capacity of oils. ISO, 2000.Google Scholar
  34. [34]
    Sosa M, Sellgren U, Björklund S, Olofsson U. In situ runningin analysis of ground gears. Wear 352–353: 122–129 (2016)CrossRefGoogle Scholar
  35. [35]
    Brandão J A, Cerqueira P, Seabra J H O, Castro M J D. Measurement of mean wear coefficient during gear tests under various operating conditions. Tribol Int 102: 61–69 (2016)CrossRefGoogle Scholar
  36. [36]
    Sjöberg S, Sosa M, Andersson M, Olofsson U. Analysis of efficiency of spur ground gears and the influence of running-in. Tribol Int 93: 172–181 (2016)CrossRefGoogle Scholar
  37. [37]
    Schultheiss H, Tobie T, Stahl K. The effect of selected grease components on the wear behavior of grease-lubricated gears. J Tribol 138(1): 011602 (2016)CrossRefGoogle Scholar
  38. [38]
    Mallipeddi D, Norell M, Sosa M, Nyborg L. Influence of running-in on surface characteristics of efficiency tested ground gears. Tribol Int 115: 45–58 (2017)CrossRefGoogle Scholar
  39. [39]
    Neurouth A, Changenet C, Ville F, Octrue M, Tinguy E. Experimental investigations to use splash lubrication for high-speed gears. J Tribol 139(6): 061104 (2017)CrossRefGoogle Scholar
  40. [40]
    Fernandes C M C G, Marques P M T, Martins R C, Seabra J H O. Gearbox power loss. Part III: Application to a parallel axis and a planetary gearbox. Tribol Int 88: 317–326 (2015)CrossRefGoogle Scholar
  41. [41]
    Marques P M T, Camacho R, Martins R C, Seabra J H O. Efficiency of a planetary multiplier gearbox: Influence of operating conditions and gear oil formulation. Tribol Int 92: 272–280 (2015)CrossRefGoogle Scholar
  42. [42]
    Clarke A, Weeks I J J, Evans H P, Snidle R W. An investigation into mixed lubrication conditions using electrical contact resistance techniques. Tribol Int 93: 709–716 (2016)CrossRefGoogle Scholar
  43. [43]
    Savolainen M, Lehtovaara A. An experimental approach for investigating scuffing initiation due to overload cycles with a twin-disc test device. Tribol Int 109: 311–318 (2017)CrossRefGoogle Scholar
  44. [44]
    Wei J, Zhang A Q, Gao P. A study of spur gear pitting under EHL conditions: Theoretical analysis and experiments. Tribol Int 94: 146–154 (2016)CrossRefGoogle Scholar
  45. [45]
    Repola P, Manconi S, Amorena M, Ciulli E, Facchini M. Design of a twin disc test machine. In Proceedings of the 5th World Tribology Congress WTC 2013, Torino, Italy, 2013.Google Scholar
  46. [46]
    Ciulli E, Fazzolari F, Piccigallo B. Experimental study on circular eccentric cam–follower pairs. Proc Inst Mech Eng Part J J Eng Tribol 228(10): 1088–1098 (2014)CrossRefGoogle Scholar
  47. [47]
    Bassani R, Ciulli E, Manfredi E, Manconi S, Polacco A, Pugliese G. Experimental study on wear and fracture in aeronautical gear transmissions. In Proceedings of the 8th Biennial Conference on Engineering Systems Design and Analysis, Turin, Italy, 2006: 979–986.Google Scholar
  48. [48]
    Bassani R, Ciulli E, Manfredi E, Manconi S, Polacco A, Pugliese G. Investigation on surface damage of ground and superfinished gears under different conditions. In Proceedings of the 16th International Colloquium Tribology, Esslingen, Germany, 2008.Google Scholar
  49. [49]
    Ciulli E, Guerrieri Paleotti F S, Bartilotta I, Manconi S, Facchini M. An experimental investigation on scuffing in spur gears. In Proceedings of ECOTRIB 2011-3rd European Conference on Tribology, Vienna, Austria, 2011: 695–700.Google Scholar
  50. [50]
    Bartilotta I, Ciulli E, Manconi S, Toson E. An experimental investigation on aerospace quality gears operating in loss of lubrication condition. In Proceedings of the ASME 2012 11th Biennial Conference on Engineering Systems Design and Analysis - ESDA2012, Nantes, France, 2012.Google Scholar
  51. [51]
    Mazzitelli I, Guerrieri Paleotti F S, Forte P, Ciulli E, Amorena M, Polacco A. Bulk temperature measurements on gears for scuffing monitoring. In Proceedings of the 7th International Conference on Condition Monitoring and Machinery Failure Prevention Technologies, CM 2010 and MFPT 2010, Stratford-upon-Avon, England, 2010.Google Scholar
  52. [52]
    Barsanti M, Beghini M, Ciulli E, Monelli B D, Manconi S, Catarsi R, Demenego A. Design and realisation of a test rig for aeronautical power trasmissions. In Proceedings of the 45th Convegno Nazionale AIAS, Trieste, Italy, 2016. (In Italian)Google Scholar

Copyright information

© The author(s) 2017

Open Access: The articles published in this journal are distributed under the terms of the Creative Commons Attribution 4.0 International License (, which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.

Authors and Affiliations

  1. 1.Department of Civil and Industrial EngineeringUniversity of Pisa, Largo Lucio LazzarinoPisaItaly

Personalised recommendations