The mechanical state of cantilever gearbox housing is different from ordinary ones due to the long arm of force caused by cantilever structure. Conventional mechanical analysis methods either took cantilever gearbox housing as ordinary ones or cantilever beam. Few published papers have specially focused on mechanical analysis method for cantilever gearbox housing. This paper takes a longwall shearer cutting unit gearbox (SCUG) as an example and the mechanical analysis method is investigated according to the causes of fatigue for SCUG. Force analysis model is established for finding out regions of static fatigue caused by low-frequency loads, and local resonance analysis is used for finding out regions of vibration fatigue caused by high-frequency loads. Not only bending moment but also torque caused by gear meshing forces is taken into account in the force analysis model. Vibration response is obtained from cutting experiment, and dominant frequencies of local resonance are obtained by frequency domain analysis. Finite element model of SCUG is established, and natural frequencies and strain modes are analyzed for obtaining the main vibration modes corresponding to dominant frequencies. Hence, large stress regions caused by low and high frequency loads are obtained. Results show that the worst working condition is oblique cutting, and the stress of B-B in 600 mm cutting depth can reach 166 MPa. Obviously, 950 Hz, 1 250 Hz, and 1 400 Hz are dominant frequencies of SCUG (23rd, 25th and 27th natural frequencies). Generally, this paper proposes some principles for mechanical analysis method of cantilever gearbox housing.
WANG Jue∗ (王 珏), LI Peng (李 朋), SONG Shiyao (宋诗瑶)
. Mechanical Analysis Methods of Cantilever Gearbox Housing[J]. Journal of Shanghai Jiaotong University(Science), 2023
, 28(2)
: 233
-242
.
DOI: 10.1007/s12204-021-2316-2
[1]LIU W G, CHENG P, HE H L, et al. Review of studying on vibration fatigue [J]. Chinese Journal of Engineering Design, 2012, 19(1): 1-8 (in Chinese).
[2]YAO Q H, YAO J. Vibration fatigue in engineering structures [J]. Chinese Journal of Applied Mechanics, 2006, 23(1): 12-15, 167-168 (in Chinese).
[3]KANG M R, KAHRAMAN A. An experimental and theoretical study of the dynamic behavior of double-helical gear sets [J]. Journal of Sound and Vibration, 2015, 350: 11-29.
[4]ZHU L S, ZHANG Y M, ZHANG R, et al. Time-dependent reliability of spur gear system based on gradually wear process [J]. Eksploatacjai Niezawodnosc: Maintenance and Reliability, 2018, 20(2): 207-218.
[5]LI G Q, LIU Z M, WANG W J, et al. Fatigue crack mechanism study on high-speed EMU gearbox [J]. Journal of Mechanical Engineering, 2017, 53(2): 99-105 (in Chinese).
[6]HU W G, LIU Z M, LIU D K, et al. Fatigue failure analysis of high speed train gearbox housings [J]. Engineering Failure Analysis, 2017, 73: 57-71.
[7]WEI J, ZHANG A Q, QIN D T, et al. A coupling dynamics analysis method for a multistage planetary gear system [J]. Mechanism and Machine Theory, 2017, 110: 27-49.
[8]HE Z X, CHANG L H, LIU L. Dynamic response analysis of planetary gear transmission system coupled with gearbox vibrations [J]. Journal of South China University of Technology (Natural Science Edition), 2015, 43(9): 128-134 (in Chinese).
[9]SONG C S, ZHU C C, LIU H J, et al. Dynamic analysis and experimental study of a marine gearbox with crossed beveloid gears [J]. Mechanism and Machine Theory, 2015, 92: 17-28.
[10]WANG F, FANG Z D, LI S J, et al. Analysis optimization and experimental verification of herringbone gear transmission system [J]. Journal of Mechanical Engineering, 2015, 51(1): 34-42 (in Chinese).
[11]TAN Y Q, HU C F, ZHANG Y C, et al. Testing research on dynamic load sharing performance of encased differential planetary gearbox [J]. Journal of Mechanical Engineering, 2016, 52(9): 28-35 (in Chinese).
[12]CHANG L H, HE Z X, LIU G. Dynamic modeling of parallel shaft gear transmissions using finite element method [J]. Journal of Vibration and Shock, 2016, 35(20): 47-53 (in Chinese).
[13]HUANG G H, WANG X Y, MEI G M, et al. Dynamic response analysis of gearbox housing system subjected to internal and external excitation in high-speed train [J]. Journal of Mechanical Engineering, 2015, 51(12): 95-100 (in Chinese).
[14]ZHAI H F, ZHU C C, SONG C S, et al. Dynamic characteristics of a high-power wind turbine gearbox coupled system [J]. Journal of Vibration and Shock, 2017, 36(8): 97-104 (in Chinese).
[15]GONZA′LEZ-CRUZ C A, JA′UREGUI-CORREA J C, DOM′INGUEZ-GONZA′LEZ A, et al. Effect of the coupling strength on the nonlinear synchronization of a single-stage gear transmission [J]. Nonlinear Dynamics, 2016, 85: 123-140.
[16]LIU C Z, QIN D T, LIAO Y H. Electromechanical dynamic analysis for the drum driving system of the long-wall shearer [J]. Advances in Mechanical Engineering, 2015, 7(10): 1-14.
[17]ZHAO L J, MA L W. Thin seam shearer reliability analysis and fatigue life prediction [J]. Journal of China Coal Society, 2013, 38(7): 1287-1292 (in Chinese).
[18]ZHAO L J, TIAN Z. Vibration characteristics of thin coal seam shearer [J]. Journal of Vibration and Shock, 2015, 34(1): 195-199 (in Chinese).
[19]ZHAO L J, TIAN Z. Simulation on dynamic characteristics of cutting unit for thin seam shearer [J]. Mechanical Science and Technology for Aerospace Engineering, 2014, 33(9): 1329-1334 (in Chinese).
[20]ZHAO L J, CHEN P, SONG P. Vibration characteristic analysis of shearer cutting unit and the transmission system structure optimization [J]. Journal of Mechanical Transmission, 2015, 39(1): 131-134 (in Chinese).
[21]LIU C S. Theoretical design basis of drum shearer [M]. Xuzhou: China University of Mining and Technology Press, 2003: 128-131 (in Chinese).
[22]HUANG J. Dynamic research and dynamic-gradual coupling reliability analysis of the transmission system of a shearer cutting arm [D]. Shenyang: Northeastern University, 2016 (in Chinese).
