development and testing of friction and wear test rig

4
International Journal of Tre Volume 3 Issue 6, October 20 @ IJTSRD | Unique Paper ID – IJTSRD2 Development and Kingsley N. Nwa Lecturer, Department of Mechan ABSTRACT This research paper presents a friction a locally available materials. Sizing of the va done as specified by Society of Autom materials for the test rig were sourced loc The input shaft was sized to fit in the machines. The test rig was tested using Soy lubricant. Samples generated from the tes Absorption Spectroscopy to obtain wear Results for three wear elements showed samples ranged from 6.2 % - 10.2 % c speeds, a distinct reduction in wear me Other wear elements followed similar p predicting performance of oil lubrica conditions. The test rig is recommended in between machine failures of production productivity and profitability. KEYWORDS: Test, Rig, Lubrication, Friction 1. INTRODUCTION Friction between two bodies is generally force at their surface of contact which res on one another. The friction force, F is th to initiate or maintain motion. If W is the of one body on the other, the coefficient defined as [1]: Wear is a process of gradual removal of surfaces of solids subject to contact and s of contact surfaces are results of wear [2 include Abrasive wear, fatigue wear, corr Usually, wear is undesirable, because it m frequent inspection and replacements of p deterioration of accuracy of machine part vibrations, fatigue and consequently failur Lubrication is the application of a lub contacting surfaces, moving relative to eac aim of reducing friction [3]. In most cases, is carried by pressure generated within the frictional viscous resistance to motion o fluid between the surfaces. Lubrication m into Boundary lubrication, Eastohydrody Fluid-film lubrication. The science and technology of interact relative motion is called Tribology. Tribo from the Greek word “Tribos” meaning r end in Scientific Research and Dev 019 Available Online: www.ijtsrd.com e 28046 | Volume – 3 | Issue – 6 | September - d Testing of Friction and We ankwo, Gbashi M. Samuel, Yanshio T. Em nical Engineering, University of Agriculture, Ma nd wear test rig, developed from arious components of the rig was mobile Engineers. The required cally, constructed and assembled. e speed range of available lathe oy oil, groundnut oil and SAE 40 oil st rig were analyzed using Atomic r metal count in the oil samples. d that at 40 rpm, copper in oil concentration whereas at higher etal concentration was obtained. profile. The test rig is capable of ants in storage and operating n industries to increase mean time n equipment thereby improving n, Wear, Design How to c Nwankwo T. Emmaue of Friction in Inter Journal of Scientific R and Deve (ijtsrd), 2456-6470 Volume-3 | October pp.147-150 https://ww 8046.pdf Copyright Internation Scientific Journal. Th distributed the terms Creative C Attribution (http://cre by/4.0) y defined as the sists their sliding he force required normal reaction t of friction, µ is (1) a material from sliding. Damages 2]. Types of wear rrosion wear etc. makes necessary parts and leads to ts. Wear induces re of the parts. bricant between ch other with the , the applied load e fluid due to the of the lubricating may be classified ynamic and Full ting surfaces in ology is derived rubbing. It is the study of the friction, lubrica surfaces with a view of unde in detail and then prescrib applications [4]. Variables in load, velocity, contact area, s environment, material of co hardness of contact face and A test rig is an apparatus or e the performance of any mec test rigs are devices used f wear. Laboratory friction and systems of simple geometry cylinder or disc against whi different curvature is presse in combination with ferrog counters, friction and we accurately. These tests asse ability of a lubricant to perm without scuffing, seizure material destruction. This study developed and ev friction and wear test rig to performance of lubricating o 2. COMPONENTS AND ME 2.1. Components of the Te The Test Rig is made of the bevel gears, oil plug, webbed velopment (IJTSRD) e-ISSN: 2456 – 6470 October 2019 Page 147 ear Test Rig mmauel akurdi, Benue, Nigeria cite this paper: Kingsley N. | Gbashi M. Samuel | Yanshio el "Development and Testing and Wear Test Rig" Published rnational Trend in Research elopment ISSN: 0, | Issue-6, 2019, 0, URL: ww.ijtsrd.com/papers/ijtsrd2 © 2019 by author(s) and nal Journal of Trend in Research and Development his is an Open Access article d under s of the Commons n License (CC BY 4.0) eativecommons.org/licenses/ ation and wear of engineering erstanding surface interactions bing improvements in given n friction and wear testing are surface finish, sliding distance, ontact face, type of lubricant, temperature [5]. equipment used for measuring chanical equipment [6]. Tribo for investigating friction and d wear tests utilize tribometer y that may include a rotating ich another solid specimen of ed [7]. When test rigs are used graphic analyzers and metal ar can be measured fairly ess predominantly the overall mit rubbing surfaces to operate or other manifestation of valuated the performance of a o be used for measuring the ils. ECHANISM OF OPERATION est Rig e helical spring, shaft, screw, d lever, and fasteners. IJTSRD28046

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This research paper presents a friction and wear test rig, developed from locally available materials. Sizing of the various components of the rig was done as specified by Society of Automobile Engineers. The required materials for the test rig were sourced locally, constructed and assembled. The input shaft was sized to fit in the speed range of available lathe machines. The test rig was tested using Soy oil, groundnut oil and SAE 40 oil lubricant. Samples generated from the test rig were analyzed using Atomic Absorption Spectroscopy to obtain wear metal count in the oil samples. Results for three wear elements showed that at 40 rpm, copper in oil samples ranged from 6.2 10.2 concentration whereas at higher speeds, a distinct reduction in wear metal concentration was obtained. Other wear elements followed similar profile. The test rig is capable of predicting performance of oil lubricants in storage and operating conditions. The test rig is recommended in industries to increase mean time between machine failures of production equipment thereby improving productivity and profitability. Kingsley N. Nwankwo | Gbashi M. Samuel | Yanshio T. Emmauel "Development and Testing of Friction and Wear Test Rig" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-3 | Issue-6 , October 2019, URL: https://www.ijtsrd.com/papers/ijtsrd28046.pdf Paper URL: https://www.ijtsrd.com/engineering/mechanical-engineering/28046/development-and-testing-of-friction-and-wear-test-rig/kingsley-n-nwankwo

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Page 1: Development and Testing of Friction and Wear Test Rig

International Journal of Trend in Scientific Research and Development (IJTSRD)Volume 3 Issue 6, October 2019

@ IJTSRD | Unique Paper ID – IJTSRD28046

Development and Testing

Kingsley N. Nwankwo

Lecturer, Department of Mechanical Engineering, University

ABSTRACT

This research paper presents a friction and wear test rig, developed from

locally available materials. Sizing of the various components of the rig was

done as specified by Society of Automobile Engineers. The required

materials for the test rig were sourced locally, constructed and assembled.

The input shaft was sized to fit in the speed range of available lathe

machines. The test rig was tested using Soy oil, groundnut oil and SAE 40 oil

lubricant. Samples generated from the test rig were analyze

Absorption Spectroscopy to obtain wear metal count in the oil samples.

Results for three wear elements showed that at 40 rpm, copper in oil

samples ranged from 6.2 % - 10.2 % concentration whereas at higher

speeds, a distinct reduction in wear metal concentration was obtained.

Other wear elements followed similar profile. The test rig is capable of

predicting performance of oil lubricants in storage and operating

conditions. The test rig is recommended in industries to increase mean time

between machine failures of production equipment thereby improving

productivity and profitability.

KEYWORDS: Test, Rig, Lubrication, Friction, Wear, Design

1. INTRODUCTION

Friction between two bodies is generally defined as the

force at their surface of contact which resists their sliding

on one another. The friction force, F is the force required

to initiate or maintain motion. If W is the normal reaction

of one body on the other, the coefficient of friction, µ is

defined as [1]:

� � �

Wear is a process of gradual removal of a material from

surfaces of solids subject to contact and sliding. Damages

of contact surfaces are results of wear [2]. Types of wear

include Abrasive wear, fatigue wear, corrosion wear etc.

Usually, wear is undesirable, because it makes necessary

frequent inspection and replacements of parts

deterioration of accuracy of machine parts. Wear induces

vibrations, fatigue and consequently failure of the parts.

Lubrication is the application of a lubricant between

contacting surfaces, moving relative to each other with the

aim of reducing friction [3]. In most cases, the applied load

is carried by pressure generated within the fluid due to the

frictional viscous resistance to motion of the lubricating

fluid between the surfaces. Lubrication may be classified

into Boundary lubrication, Eastohydrodynamic and Full

Fluid-film lubrication.

The science and technology of interacting surfaces in

relative motion is called Tribology. Tribology is derived

from the Greek word “Tribos” meaning rubbing. It is the

International Journal of Trend in Scientific Research and Development (IJTSRD)2019 Available Online: www.ijtsrd.com e

28046 | Volume – 3 | Issue – 6 | September -

nd Testing of Friction and Wear Test Rig

Kingsley N. Nwankwo, Gbashi M. Samuel, Yanshio T. Emmauel

f Mechanical Engineering, University of Agriculture, Makurdi, Benue, Nigeria

This research paper presents a friction and wear test rig, developed from

locally available materials. Sizing of the various components of the rig was

done as specified by Society of Automobile Engineers. The required

ere sourced locally, constructed and assembled.

The input shaft was sized to fit in the speed range of available lathe

machines. The test rig was tested using Soy oil, groundnut oil and SAE 40 oil

lubricant. Samples generated from the test rig were analyzed using Atomic

Absorption Spectroscopy to obtain wear metal count in the oil samples.

Results for three wear elements showed that at 40 rpm, copper in oil

10.2 % concentration whereas at higher

ar metal concentration was obtained.

Other wear elements followed similar profile. The test rig is capable of

predicting performance of oil lubricants in storage and operating

conditions. The test rig is recommended in industries to increase mean time

een machine failures of production equipment thereby improving

Test, Rig, Lubrication, Friction, Wear, Design

How to cite this paper

Nwankwo | Gbashi M. Samuel |

T. Emmauel "Development and Testing

of Friction and Wear Test Rig" Published

in International

Journal of Trend in

Scientific Research

and Development

(ijtsrd), ISSN:

2456-6470,

Volume-3 | Issue

October 2019,

pp.147-150, URL:

https://www.ijtsrd.c

8046.pdf

Copyright © 2019 by author(s) and

International Journal of Trend in

Scientific Research and Development

Journal. This is an Open Access article

distributed under

the terms of the

Creative Commons

Attribution License (CC BY 4.0)

(http://creativecommons.org/licenses/

by/4.0)

Friction between two bodies is generally defined as the

force at their surface of contact which resists their sliding

is the force required

is the normal reaction

of one body on the other, the coefficient of friction, µ is

(1)

Wear is a process of gradual removal of a material from

ject to contact and sliding. Damages

of contact surfaces are results of wear [2]. Types of wear

include Abrasive wear, fatigue wear, corrosion wear etc.

Usually, wear is undesirable, because it makes necessary

frequent inspection and replacements of parts and leads to

deterioration of accuracy of machine parts. Wear induces

vibrations, fatigue and consequently failure of the parts.

Lubrication is the application of a lubricant between

contacting surfaces, moving relative to each other with the

ing friction [3]. In most cases, the applied load

is carried by pressure generated within the fluid due to the

frictional viscous resistance to motion of the lubricating

fluid between the surfaces. Lubrication may be classified

astohydrodynamic and Full

The science and technology of interacting surfaces in

relative motion is called Tribology. Tribology is derived

meaning rubbing. It is the

study of the friction, lubrication

surfaces with a view of understanding surface interactions

in detail and then prescribing improvements in given

applications [4]. Variables in friction and wear testing are

load, velocity, contact area, surface finish, sliding

environment, material of contact face, type of lubricant,

hardness of contact face and temperature [5].

A test rig is an apparatus or equipment used for measuring

the performance of any mechanical equipment [6]. Tribo

test rigs are devices used for investigating friction and

wear. Laboratory friction and wear tests utilize tribometer

systems of simple geometry that may include a rotating

cylinder or disc against which another solid specimen of

different curvature is pressed [7]. When test rigs ar

in combination with ferrographic analyzers and metal

counters, friction and wear can be measured fairly

accurately. These tests assess predominantly the overall

ability of a lubricant to permit rubbing surfaces to operate

without scuffing, seizure o

material destruction.

This study developed and evaluated the performance of a

friction and wear test rig to be used for measuring the

performance of lubricating oils.

2. COMPONENTS AND MECHANISM OF OPERATION

2.1. Components of the Test

The Test Rig is made of the helical spring, shaft, screw,

bevel gears, oil plug, webbed lever, and fasteners.

International Journal of Trend in Scientific Research and Development (IJTSRD)

e-ISSN: 2456 – 6470

October 2019 Page 147

nd Wear Test Rig

Yanshio T. Emmauel

Makurdi, Benue, Nigeria

How to cite this paper: Kingsley N.

Nwankwo | Gbashi M. Samuel | Yanshio

T. Emmauel "Development and Testing

of Friction and Wear Test Rig" Published

in International

Journal of Trend in

Scientific Research

and Development

(ijtsrd), ISSN:

6470,

3 | Issue-6,

October 2019,

150, URL:

https://www.ijtsrd.com/papers/ijtsrd2

Copyright © 2019 by author(s) and

International Journal of Trend in

Scientific Research and Development

Journal. This is an Open Access article

distributed under

the terms of the

Creative Commons

Attribution License (CC BY 4.0)

http://creativecommons.org/licenses/

study of the friction, lubrication and wear of engineering

surfaces with a view of understanding surface interactions

in detail and then prescribing improvements in given

Variables in friction and wear testing are

load, velocity, contact area, surface finish, sliding distance,

environment, material of contact face, type of lubricant,

hardness of contact face and temperature [5].

A test rig is an apparatus or equipment used for measuring

the performance of any mechanical equipment [6]. Tribo

for investigating friction and

wear. Laboratory friction and wear tests utilize tribometer

systems of simple geometry that may include a rotating

cylinder or disc against which another solid specimen of

different curvature is pressed [7]. When test rigs are used

in combination with ferrographic analyzers and metal

counters, friction and wear can be measured fairly

accurately. These tests assess predominantly the overall

ability of a lubricant to permit rubbing surfaces to operate

without scuffing, seizure or other manifestation of

This study developed and evaluated the performance of a

friction and wear test rig to be used for measuring the

performance of lubricating oils.

COMPONENTS AND MECHANISM OF OPERATION

Components of the Test Rig

The Test Rig is made of the helical spring, shaft, screw,

bevel gears, oil plug, webbed lever, and fasteners.

IJTSRD28046

Page 2: Development and Testing of Friction and Wear Test Rig

International Journal of Trend in Scientific Research and Development (IJTSRD) @ www.ijtsrd.com eISSN: 2456-6470

@ IJTSRD | Unique Paper ID – IJTSRD28046 | Volume – 3 | Issue – 6 | September - October 2019 Page 148

2.2. Mechanism of Operation

The proposed design was actualized by assembling four

bevel gears (two pinions and two wheels) in a gear

housing. A shaft machined to fit into the jaw of a centre

lathe and welded to one of the pinion gears was employed

to transfer torque from the centre lather to the bevel

gears. While performing a test, the center lathe is used to

turn the bevel gears at selected speeds. Pressure between

the meshing gears is achieved by means of a power screw

connected to a spring of known stiffness. During tests, the

system remains submerged in a lubricant carried by the

gear housing. A thermometer is used to take the

temperature reading of each oil sample after every

running operation. After running a sample at a specific

speed, load and time, the oil sample is drained and taken

for metal count. The efficiency of a lubricant is determined

by the degree to which it reduces the amount of metal

worn into the oil.

3. DESIGN CONCEPT

The design of the various components of the test rig was

done, making reference to the scholarly works of Khurmi

R. S. and Gupta J.K. [8-9].

3.1. Design of the Spring

The spring constant, K can be determined from the

relationship below:

� � ��

�� � (2)

Where G = Shear modulus of material, d = Spring wire

diameter, D = Mean diameter of spring, and na = Number

of active coils.

The shear modulus, G is given as:

� � �

�(���) (3)

Where E = Young’s modulus and v = Poisson’s ratio.

The mean diameter, D is given as:

� � ������ − � (4)

Where Douter = Outer diameter.

The maximum force the spring can, Fmax is expressed as:

� !" � �(#$��� − #%�&'�) (5)

Where Lfree = Free length of spring, Lsolid = Solid length of

spring.

The maximum shear stress, τmax is given as:

( !" �)�

*��� !" (6)

Where W is the Wahl correction factor, defined as:

+ �,-.�

,-.,+0.2�3

- (7)

Where C is given as:

4 ��

� (8)

3.2. Design of Shaft for the Pinion

Since the pinion is subjected to torsion only, the diameter

of the shaft, d may be obtained as follows: 5

6�7

� (9)

8 ��

� (10)

Where T = Twisting moment or torque transmitted by

shaft, τ = Shear stress, r = Distance of neural axis from

outermost fibre and J = Polar moment of inertia, defined

as:

9 �*

:��, (11)

The Torque transmitted by the shaft can thus be expressed

as:

; �7

�2(�: (12)

Or

; �20<

�*� (13)

Where: P = Power transmitted by shaft and N = Speed of

shaft in rpm

3.3. Design of the Screw

In order to design a screw jack for a load W, the following

procedure may be adopted:

The core diameter of the screw, dc considering only the

compressive stress, σc may be calculated from:

=> �)?

�@A (14)

The effort at the handle required to raise the load, Pr is

given as:

B� � +CDE(F + G) (15)

The effort at the handle required to lower the load, Pl is

given as:

B& � +CDE(F − G) (16)

Where φ = Angle of friction and α = Screw helix angle.

The torque required to raise the load, Tr is given as:

;� �<�H

� (17)

The torque required to lower the load, Tl is given as:

;& �<�H

� (18)

Where dm = Mean diameter of the screw

This means,

;� � +CDE(F + G)�

� (19)

And

;& � +CDE(F − G)�

� (20)

3.4. Assembly of Test Rig

The test rig was assembled as shown below (Figure 1-3).

The parts include 1. Webbed lever 2. Power screw 3.

Compression spring 4. Test rig casing 5. Gear housing 6.

Pinion shaft 7. Bearing 8. Oil plug 9. Bolt and nut 10 Bevel

gear

Page 3: Development and Testing of Friction and Wear Test Rig

International Journal of Trend in Scientific Research and Development (IJTSRD) @ www.ijtsrd.com eISSN: 2456-6470

@ IJTSRD | Unique Paper ID – IJTSRD28046 | Volume – 3 | Issue – 6 | September - October 2019 Page 149

Figure1: Test Rig - Front View

Figure2: Test Rig – Sectional Front View

Figure3: Test Rig – Three Dimensional Model View

4. TESTING OF RIG

4.1. Generation of Oil Samples

The test was conducted using Soy oil, Groundnut oil and

SAE 40 lubricating oil. A total of 9 test samples were

generated after running the aforementioned oils at 3

different speeds for a constant load at 5 minutes each as

shown in the Table 1 below.

Table1: Samples Generated for Metal Count

SN SAMPLE SAMPLE DESCRIPTION SPEED (RPM)

1 S1 Soy Oil 40

2 S2 Soy Oil 90

3 S3 Soy Oil 120

4 S4 G/Nut Oil 40

5 S5 G/Nut Oil 90

6 S6 G/Nut Oil 120

7 S7 SAE 40 Oil 40

8 S8 SAE 40 Oil 90

9 S9 SAE 40 Oil 120

4.2. Metal Count

Oil samples generated above were taken for metal count

using Atomic Absorption Spectroscopy. Results for the test

are presented in the section that follows.

5. RESULT AND DISCUSSION

5.1. Result

Line graphs obtained from results of metal count are

shown in Figure 4 – 6. Figure 4 shows the Change in

Percentage Concentration of Metals with Input Shaft

Speed for Soy Oil (S1), Figure 5 shows the Change in

Percentage Concentration of Metals with Input Shaft

Speed for SAE 40 Oil (S3) and Figure 6 shows the Change

in Percentage Concentration of Metals with Input Shaft

Speed for Groundnut Oil (S2)

Figure4: Change in Percentage Concentration of

Metals with Input Shaft Speed for Soy Oil (S1)

Figure5: Change in Percentage Concentration of

Metals with Input Shaft Speed for SAE 40 Oil (S3)

Page 4: Development and Testing of Friction and Wear Test Rig

International Journal of Trend in Scientific Research and Development (IJTSRD) @ www.ijtsrd.com eISSN: 2456-6470

@ IJTSRD | Unique Paper ID – IJTSRD28046 | Volume – 3 | Issue – 6 | September - October 2019 Page 150

Figure6: Change in Percentage Concentration of

Metals with Input Shaft Speed for Groundnut Oil (S2)

5.2. Discussion

Comparing figure 4 – 6, it is observed that at 40rpm, the

Soy oil sample (S1) contained 10.2 % Cu, while the

Groundnut oil sample (S2), and SAE 40 oil sample (S3)

contained 6.2 % Cu and 6.6 % Cu respectively. The source

of copper could be traced to the gears and bearings of the

friction and wear test rig. The good performance of the

groundnut oil sample at low speed of 40 rpm could be

attributed to the presence of fatty acids in the oil that

formed metallic soaps with the surface of the gears and

bearings thereby producing a lubrication film that was

able to resist friction and wear. This observation agrees

with Nnuka et al. [7] who found that by adding small

quantity of natural oil to mineral oil lubricant, there was

an improvement in wear and friction performance. For the

samples compared above, it is observed that as speed

increased, there is a general drop in percentage

concentration of copper in the samples. This is in

agreement with [10] who observed that at low speeds,

lubricants tend to perform under boundary lubrication

conditions where composition and properties of lubricants

determine lubrication performance. However, as the speed

increases, hydrodynamic lubrication condition sets in and

the primary property that matter is viscosity.

Also from the figures compared, it is observed that at

40rpm, Manganese stood out but as the speed increased,

Magnesium exceeded Manganese while Copper dropped

progressively due to transformation from boundary

lubrication condition to hydrodynamic condition.

6. CONCLUSION

The friction and wear test rig has been designed and

tested. The test rig is used in combination with

ferrographic analyzers, metal counters, gas liquid

chromatographs, etc. for predicting the ability of oil

lubricants to reduce friction and wear. The test rig plays

an important role in lubrication because it is pivotal in

determining the performance of oil lubricants at different

storage and working conditions. The test rig is

considerably cheap compared to the conventional testing

devices.

REFERENCES

[1] Harold, A. R. (2006). “Friction Lubrication and Wear”,

in David T. (ed.) Mechanical Engineering Handbook.

Michigan: McGraw-Hill. Pp 7.1-7.23,

[2] Alfred Z. (2006). Wear Patterns and Laws of Wear –

A Review. Journal of Theoretical and Applied

Mechanics. 44: 219-253.

[3] Reiger N. F. (1967). Lubrication Design, Mechanical

Technology Inc, Latham, New York, pp54-98

[4] Bharat B. (2001); Introduction to Tribology; John

Wiley,

[5] Sanjay K. and Sen S. S. (2014). Wear and Friction in

Journal Bearing: A Review. International Journal of

Engineering and Management Research.

[6] Raajeshkrishna R. G. and Vikrant M. S. (2012). Design

of Journal Bearing Test Rig. Master’s Thesis.

Department of Mecahanical Engineering. Blekinge

Institute of Technology, Karlskrona, Sweden

[7] Nnuka, E. E. Oseni, M. I. and Ette, A. O. (2005).

Evaluation of Tribometric Characteristics of Selected

Natural Oils. Nigerian Journal of Mechanical

Engineering, 3(1), 1-12

[8] Khurmi R. S. and Gupta J. K. (2005a): Theory of

Machies, Eurasias Publishing House Ltd, pp57 – 654

[9] Khurmi R. S. and Gupta J. K. (2005b): Machine

Design, Eurasias Publishing House Ltd, pp56– 87.

[10] Kragelsky I. V., and Alisin V. V. (1982). Friction Wear

Lubrication: Tribology Handbook. McGraw-Hill.

Texas. 264pp