Vibration analysis of nylon gear box utilizing statistical method C. Poongodi a , B.S. Hari b , S. Arunkumar b,⇑ a Department of Information Technology, Kongu Engnineering College, Erode 638060, India b Department of Mechanical Engineering, Kongu Engnineering College, Erode 638060, India article info Article history: Received 13 May 2020 Accepted 18 May 2020 Available online xxxx Keywords: Frequency domain Kurtosis Nylon gear RMS Standard deviation Time domain Variance abstract Gears are important element in a variety of industrial applications such as medical and automotive sec- tors. In the medical field it is used in surgical instruments, Biopsy instrumentation and Dental implant products. In automotive sectors like Electrical Throttle Controls, Steering Systems, Instrument Clusters, Window and Door Latch systems. Though the plastic gears have less heat dissipation, high wear resis- tance and self-lubrication properties, there may be defects in nylon gears in runtime applications. The defects include surface fatigue like pitting, scuffing, scratching and some common defects like flash, warping, bubbles etc. The gear defects are often identified under switch off condition and gear are checked. There are defect testing methods like image processing. In this work the defects were identified when the system is in running condition, by analysing the vibration signals obtained from the system under varying load and speed conditions. Gears are designed based on the parameters like module, pitch circle diameter, no of teeth and bending load capacity. In this work, the experimental setup is fabricated for testing the gears at three different sets of speeds. By varying the speed of transmission between two shafts both in loading and unloading conditions, the sound signals are acquired using sound sensor and sound signals are processed using MATLAB. The time- domain signal and frequency domain signals are used to detect the failure in nylon gear. Using the parameters like kurtosis, RMS, variance and standard deviation value the good gears and defective gears are compared. By using this method the defects in nylon gears can be identified easily. Ó 2020 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of the scientific committee of the International Confer- ence on Nanotechnology: Ideas, Innovation and Industries. 1. Introduction Gears are used for transmission of motion from one shaft to another. In this research work nylon gear is analysed, which has a variety of applications in engineering field, such as textile, auto- mobile, home appliances[1]. The gears would transmit the rota- tional motion perfectly, when there is no geometrical errors in it, which suggests the constant speed input will be same as the out- put[2]. Any motion that repeats itself after an interval of time is termed vibration or oscillation. The gear mesh frequency will be repeated after a particular interval of time, if the interval is similar then it shows that the gears are defect free. Noise and vibration measurement and signal analysis are important tools when experimentally investigating gear noise [3– 7]. Gears create noise at specific frequencies, associated with the rotational speed and number of teeth of the gear. It is also possible to detect different errors like for instance run out (eccentricity) thanks to side-band generation[8,9]. Closely related is additionally vibration measurement and signal analysis for the aim of gear fault detection, utilized in machine diagnostics so as to detect gear fail- ures before catastrophic failure occurs[5]. Dynamic models of the system consisting of gears, shafts, bear- ings and gearbox casing are useful in order to understand and pre- dict the dynamic behavior of a gearbox[4,8]. For relatively simple gear systems it is possible to use lumped parameter dynamic mod- els with springs, masses and viscous damping. For more complex models, which include for example the gearbox casing, finite ele- ment modeling is often used. Faults in gears leads to breakdown of rotating machinery lead- ing to serious consequences of plant operation make it worse to perform the operation required to be done nowadays. Gear is an important part of all machinery in https://doi.org/10.1016/j.matpr.2020.05.441 2214-7853/Ó 2020 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of the scientific committee of the International Conference on Nanotechnology: Ideas, Innovation and Industries. ⇑ Corresponding author. E-mail address: arunmts12@gmail.com (S. Arunkumar). Materials Today: Proceedings xxx (xxxx) xxx Contents lists available at ScienceDirect Materials Today: Proceedings journal homepage: www.elsevier.com/locate/matpr Please cite this article as: C. Poongodi, B. S. Hari and S. Arunkumar, Vibration analysis of nylon gear box utilizing statistical method, Materials Today: Pro- ceedings, https://doi.org/10.1016/j.matpr.2020.05.441