gear test rig - a review - · pdf filegear test rig - a review a. p. arun*1, 2a.p.senthil...

International Journal of Mechanical & Mechatronics Engineering IJMME-IJENS Vol:14 No:05 16

140205-9696-IJMME-IJENS © October 2014 IJENS I J E N S

Gear Test Rig - A Review

A. P. Arun*1, A.P.Senthil kumar

2, B. Giriraj

3, A. Faizur rahaman

4

1Department of Mechanical Engineering, Kumaraguru College of Technology, Coimbatore - 641049, India.

*[email protected] 2,3

Department of Mechanical Engineering, PSG College of Technology, Coimbatore-641004, India. [email protected] 4Department of Mechanical Engineering, CSI College of Engineering, Nilgiris-643215, India.

[email protected]

Abstract-- In the past decades, many impressive progress had

been made in the field of simulation and analysis, even though

experiments are necessary in many fields to conduct investigation

on mechanical components [26]. Gears are one of the such

components that needed to be tested experimentally. Therefore,

test rigs are required with the possibility of varying speed and

torque during the test, based on the requirement. In this paper,

development of test rigs for evaluating the performance of gear

has been studied. The main objective of this paper is to give

researchers an idea about the physical development of a gear test

rig. Test rig developed by various researchers based on the

parameters to be tested were discussed with schematic

representation and test procedure. A new gear test rig also

fabricated by the authors and development procedure of the

same was discussed.

Index Term— gear testing machine, FZG test rig, Back-to-back

gear test rig, simple gear test rig.

I. INTRODUCTION Power transmitted by Gear boxes were fluctuating strongly in

many of the applications. For example, in automobiles, based

on the condition of driving, torque and speed varies. In

machining operations, based on the material to be machined,

torque and speed varies. These evidences show that, test rigs

are needed for testing such gear boxes. Performance of gears

depends on parameters like its design, material,

manufacturing and working environment. Developing a

mathematical model to predict the life of gear will be difficult

because of interaction between these parameters [1-7].

Therefore a separate test rig is needed for predicting the life

of the gears. Sometimes noise from the gearbox becomes a

dominating one this creates a bad impression over the gear

quality. To overcome this noise from the gear to be reduced

10–15 dB compared with other noise sources like engine

noise. So gears to be tested for noise under controlled

environment [8, 9]. Other than that when the gear pair

exceeds its load carrying capacity different modes of failure

will occur like, micro-pitting, pitting, tooth breakage,

scuffing, excessive wear, etc. other parameters like the gear‟ s

dynamic behavior and its efficiency also to be investigated

experimentally [26]. Therefore, a test rig which allows to test

gears under controlled environment is needed. A simple

construction of a test rig is shown in Fig. 1 which consists of

a prime mover (motor), loading device (brake, dynamo meter,

pump, etc.) and the test gear box which is to be mounted

between the prime mover and loading device.

Fig. 1. Simple construction of a gear test rig

II. GEAR TEST RIG FOR MEASURING VARIOUS

PARAMETERS

A. Noise Testing

To investigate noise emission from a vehicle gearbox and gear

fault detection and diagnosis Essam Allam et al [10], Hui Li

[11] used the following procedure for investigation and the

schematic representation of their test rig is shown in Fig.2, the

gearbox was running at 200 RPM at 10 mm for 3hours to

make the gearbox settle dynamically and it reaches a

stabilized temperature of 60°C. Input speed of 100 to 500

RPM with a torque of 2.5 to 15 Nm was used as test condition.

Condenser 1/2- microphone with 4189A- 021 type

preamplifier was placed in the center of the gearbox front

casing used to measure the SPLs signals, Bruel and Kjaer (B

and K) portable and multichannel PULSE type 3560-B-X05

was used to analyze the signal occurred. C. Brecher, et al [14]

conducted investigation on gear noise for that acceleration

sensor are mounted close to the bearings and a free-field



microphone is located close to the tooth mesh. The

microphone was located close to the tooth mesh and

acceleration sensors are mounted near the bearing. Fig.3.

shows the schematic representation of the test rig used for this

investigation.Åkerblom M [25] uses a Mechanical power

recirculation type test rig. Were two identical gear boxes were

connected through a universal joint as shown in Fig.4. One of

the gear boxes was tilted with the aid of hydraulic cylinder for

applying load. Accelerometers were mounted on the gearbox

for vibration measurement. Microphones were used to

measure the noise. The total setup was mounted over a

concrete stage. To conduct investigation on the resonance

frequency behavior of spur gears Shuting Li [20] used a power

circulating test rig was used. Rubber couplings were used to

avoid the effect of vibration signals from motor and shaft.

Construction of this test rig is shown in Fig.5.

Fig. 2. Test rig for investigating gear noise emission [10]

Fig. 3. Test rig for investigating gear noise [14]



Fig. 4. Test rig for vibration measurement [25]

Fig. 5. Test rig to investigate the resonance frequency [20]

B. Lubricant viscosity and additives

T. L. Krantz et al [12] investigates the influence of lubricant

viscosity and additives on gear wear, speed of the motor was

maintained at 10000 RPM and it continuously runs for 24

hours. Hydraulic pressure load is applied. Lubricant oil was

supplied at a constant flow rate and temperature measured by



a separate system. 55 μm fiberglass filter was used to remove

wear particles, for each test 3.8 liters of lubricant was used. A

vibration transducer is used to stop the test rig if fatigue

damage occurred over the gear surface. The schematic

representation of test rig used in this investigation is shown in

Fig.6.

To understand the effect of lubricant contamination on gear

wear Mohamed Rafik Sari et al [15] used the test rig as shown

in Fig.7, to conduct the test pinion was rotated at 200 RPM

with a load of 265 N applied by a hydraulic control system.

Lubricating oil was supplied by a gravity feed system so is to

maintain constant meniscus of liquid in the contact area of

gears.

Fig. 6. Test rig to investigate the influence of lubricant viscosity [12]



Fig. 7. Test rig to investigate the effect of lubricant contamination on gear wear [15]

C. Strength of the Gear

Qi Zhang, et al [13] evaluates contact fatigue strength of the

gear, for that motor speed of 1440 RPM was maintained with

1000 Nm. Load clutch is carried by front shaft which is used

to apply the load. The flanges of the load clutch are twisted

relative to each other and bolted together for applying load.

Torque was applied by weights and load lever. Dip lubrication

of 85W/90 GL-5 type heavy-duty automobile gear oil was

used and the temperature of lubricating oil was maintained

constantly by the application of heating and cooling coil. Test

rig used for this work is shown in Fig. 8. To know the contact

fatigue performance of the gear V. Moorthy et al [16] used the

test rig as shown in Fig. 9 input speed of 3000 RPM was

maintained with two different torque levels of 460 NM and

570 NM. Aeroshell oil at 100 ◦C was used as lubricating oil.

Identification of progressive contact fatigue damage was

analyzed by tooth profile measurement at each stage.

Fig. 8. Test rig to evaluate the contact fatigue strength of the gear [13]



Fig. 9. Test rig to evaluate contact fatigue performance of the gear [16]

D. GEAR FAILURE INVESTIGATION

For monitoring distributed pitting failure in gears Hasan

Ozturk et al [17] used the test rig as shown in Fig. 10. Speed

range of 0 to 3000 RPM. Stiffened structure was used to

mount Motor and gear box. Two PCB 352A76 type

accelerometer was used to detect vibration signal produced by

the gears. For determining the resistance to scuffing W.

Tuszynskin et al [19] used FZG T-12U type test rig whose

schematic representation is shown in Fig.11, an AC Squirrel

cage motor makes the input shaft to run at 3000 RPM. A mass

comparator was used to measure the wear rate of the gear.K.

Mao [21] designed polymer composite gear and he developed

a test rig for wear measurement as shown in Fig.12. where the

movement of the bearing block was recorded using capacitive

transducer of non contact type in order to measure gear wear.

R. Yakut et al [23] et al, uses a FZG test rig as shown in

Fig.13. for finding the load capacity of PC/ABS spur gears

and to investigate gear damage. Load range chosen was 16.07,

20.5 and 29.36, rotational speed range was 750, 1000 and

1500. Pitch line velocity (m/s) taken as 3.57, 4.76 and 7.14.

DC electric motor of 7.5 KW is used for producing input

power. Weight loss measured with 0.0001sensitivity weighing

machine. The mean temperature of gear tooth was measured

with impact infratherm pyrometer 510-N at a distance of 7mm

from the gear meshing point.

Fig. 10. Test rig for monitoring distributed pitting failure in gear [17]



Fig. 11. Test rig for determining the resistance to scuffing [19]

Fig. 12. Test rig for wear measurement [21]



Fig. 13. Test rig for finding the load capacity [23]

E. GEAR EFFICIENCY AND PERFORMANCE

Seong Han Kim et al, [18] predicted efficiency of the plastic

worm wheel, input torque was applied by a servo motor and

resistant torque was applied by a power brake. Torque range

of 2 Nm to 60 Nm with angular speed range of 30 deg/s to 360

deg/s was chosen for conducting the tests. Physical

arrangement of the test rig is shown in Fig. 14. To understand

the performance of glass fiber reinforced nylon 6 spur gear

based on the rotational speed, S. Senthilvelan, and R.

Gnanamoorthy [22] developed a power absorption test rig and

its schematic representation is shown in Fig.15. and they

followed the following procedure to test its performance.

Testing of gears were done at torque levels of 0.8, 1.5, 2, 2.5

and 3 Nm., Lewis equation was used to compute bending

stress on gear tooth. 600, 800, 1000 and 1200 RPM is the gear

rotational speeds used to conduct tests. Testing of gears were

conducted under dry conditions. Gears were continuously

running until it fails or until 5 million cycles whichever is

earlier and using microscope failure mechanisms of gears

were observed. T. T. Petry-Johnson et al,[24] developed a

four-square-type gear test rig(Fig. 16) to investigate spur gear

efficiency. The concept of this test rig is that one gear from

each gearbox is connected to the corresponding gear of the

other gearbox. Input is given by a high-speed spindle which

driven by a belt with a 3:1 ratio speed increase from a variable

speed AC motor. Seperate temperature controlled oil

circulation system is used which gives 2.25 LPM at gear mesh

zone. Testing done at 10000rpm with a gear pitch-line velocity

of 48 m/s. Maximum torque value applied it 680 Nm. Test

duration was selected as 10 min, where the last 5 min used for

data measurement.



Fig. 14. Test rig for predicting efficiency of the gear [18]

Fig. 15. Schematic of the power absorption gear test rig [22]

Fig. 16. Four-square-type gear test rig to investigate spur gear efficiency [24]



F. DEVELOPMENT OF SIMPLE GEAR TEST RIG WITH

PUMP AS LOADING DEVICE

Concrete basement was created for placing the frame. The

Frame was bolted to the basement. Motor, brackets for

holding gear box and pump were placed over the frame. 3 Φ

50HP AC induction motor provides input power. Loading of

gear is done by a gear pump with hydraulic system. Schematic

arrange of the test rig is shown in Fig. 17.

Fig. 17. gear test rig with pump as loading device

A separate RPM controller is used to control the

speed of the motor within the range of 0 to 3000 RPM. Flange

couplings are used to connect the motor shaft with gearbox

input shaft and gearbox output shaft with pump shaft.

Eccentricity is avoided with the help of dial gauge while

connecting with flange coupling. Gear loading is done by

adjusting the pressure relief valve mounted between pump

output and storage tank. 0 to 700 bar pressure can be applied

as a load to the gear. Vibration meter with 10 to 1 kHz

frequency range is used to measure the acceleration level of

the gearbox. Decibel meter with 30 to 130 dB is used for

measuring noise level of the gear box. A J type thermocouple

is used to measure the gearbox oil temperature and infrared

thermometer with a range of -30 to 3050C is used to find the

gear tooth temperature, for that a separate hole is produced in

the gearbox above the tooth contact area.

CONCLUSION

Various kinds of gear test rigs developed by various

authors were discussed in this paper. Based on the review a

new test rig was also developed with available equipments

inside the laboratories and the data acquired from the test rig

is more reliable. The developed test rig is ready for conducting

research on gears. This paper will be more useful for

researchers in the field of gears. Based on the parameters to

measure and the test procedure, researchers can develop their

own gear test rig.

REFERENCE [1] B.J.Roylance, A.M.Koroma, J.Vizintin, I.Libuscek, “Tribological

considerations in the operation monitoring, and maintenance of

gear transmission systems”, Proc of the Intl Gearing Conf, Newcastle upon Tyne, U.K, pp 453-457,1994.

[2] C.Madhavan, “Effects of heat treatments on the surface durability

of ferrous based powder metal spur gears”, PhD thesis, IIT Madras, 1991.

[3] T.L.Krntz, M.P.Alanou, H.P.Evans and R.W.Snidle, “Surface

fatigue lives of case carburised gears with an Improved surface finish”, J of Tribology, Vol 123,pp 709- 716,Oct, 2001.

[4] Damodar Reddy, “Oil film thickness measurements in spur gears

in re-circulating test gear”, M. Tech Thesis, IT Madras 1972.

[5] M.Kato, k. Inoue, Shibata and H.Zhou,” Evaluation of the sound

power radiated by a gearbox”, Proc of the Intl Gearing conf,

Newcastle upon Tyne, UK, pp. 69-74,1994. [6] D.J.Fessett,”How to Test Gear Transmissions”, Machine Design,

Vol47, No 18, pp 61-64, July 24, 1975.

[7] D.J.Fessett, “Hardware for Testing Gear Transmissions”, Machine Design, Vol 47, No 19, pp 80-83, August 7, 1975.

[8] Hellinger W., Raffel H. Ch., Rainer G. Ph., Numerical Methods to

Calculate Gear Tranmission Noise, SAE Technical Paper 971965, 1997.

[9] Campell B., et al., Gear Noise Reduction of Automatic

Transmission Trough Finite Element Dynamic Simulation, SAE Technical Paper 971966, 1997.



[10] Essam Allam, Ibrahim Ahmed and Shawki Abouel-Seoud, “An experimental investigation of noise emission from a vehicle

gearbox system” Journal of Mechanical Engineering Research

Vol. 3(3), pp. 75-84, March 2011 [11] Hui Li1 ,Yuping Zhang and Haiqi Zheng, “Gear fault detection

and diagnosis under speed-up condition basedon order cepstrum and radial basis function neural network” Journal of Mechanical

Science and Technology, Vol. 23, pp. 2780~2789, 2009.

[12] T. L. Krantz, A. Kahraman, “An Experimental Investigation of the Influenceof the Lubricant Viscosity and Additives on Gear Wear”

Tribology Transactions, Vol. 47, pp. 138-148, 2004

[13] Qi Zhang, Jing Zhang, Changhong Wu, Zhezhu Xu and SungKi Lyu, “The Evaluation of Contact Fatigue Strength for 20MnCr5

Carburized Gear” International Journal Of Precision Engineering

And Manufacturing Vol. 15, No. 1, pp. 117-121 [14] Brecher, C. Gorgels, C. Carl and M. Brumm, “Benefit of

Psychoacoustic Analyzing Methods for Gear Noise Investigation”

Gear Technology, pp. 49-55,August 2011. [15] Mohamed Rafik Sari, Ammar Haiahem, “Effect of Lubricant

Contamination on Gear Wear” Tribol Lett , Vol. 27:119–126

,2007

[16] V. Moorthy, B.A. Shaw, “Contact fatigue performance of helical

gears with surface coatings” Wear , Vol. 276– 277 ,130– 140,

2012 [17] Hasan Ozturk , Isa Yesilyurt and Mustafa Sabuncu, “Detection

and Advancement Monitoring of Distributed Pitting Failure in

Gears” J Nondestruct Eval , Vol. 29, pp. 63–73, 2010 [18] Seong Han Kim, Min Chul Shin, Jung Won Byun, Kwang Hwan O

and Chong Nam Chu, “Efficiency Prediction of Worm Gear with

Plastic Worm Wheel” International Journal of Precision Engineering and Manufacturing, Vol. 13, No. 2, pp. 167-174

[19] W.Tuszynskin, R.Michalczewski,M.Szczerek,M.Kalbarczyk, “A

new scuffing shock test method for the determination of the resistance to scuffing of coated gears” Archives Of Civil And

Mechanical Engineering, Vol. 12 , pp. 436 – 445, 2012.

[20] Shuting Li, “Experimental investigation and FEM analysis of resonance frequency behavior of three-dimensional, thin-walled

spur gears with a power-circulating test rig” Mechanism and

Machine Theory , Vol. 43, pp. 934–963, 2008.

[21] K. Mao, “A new approach for polymer composite gear design”

Wear , Vol. 262, pp. 432–44,2007.

[22] S. Senthilvelan, R. Gnanamoorthy, “Effect of rotational speed on the performance of unreinforced and glass fiber reinforced Nylon 6

spur gears” Materials and Design , Vol. 28, pp. 765–772, 2007.

[23] R. Yakut, H. Düzcükoğlu, M.T. Demirci, “The load capacity of PC/ABS spur gears and investigation of gear damage” Archives of

Materials Science and Engineering, Vol. 40-1, pp. 41-46, 2009.

[24] T. T. Petry-Johnson A. Kahraman , N. E. Anderson, D. R. Chase, “An Experimental Investigation of Spur Gear Efficiency” Journal

of Mechanical Design , Vol. 130, Pp 062601-1 to 7, JUNE 2008,

[25] Åkerblom M. „Gear Test Rig for Noise and Vibration Testing of Cylindrical Gears‟, Proceedings OST-99 Symposium on Machine

Design, Stockholm, pp. 183–189, 1999.

[26] Athanassios Mihailidis and Ioannis Nerantzis “A New System for

Testing Gears Under Variable Torque and Speed” Recent Patents on Mechanical Engineering, Vol. 2, pp. 179-192, 2009.

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