statistical analysis of repair and maintenance of institute vehicles nerist diplomaproject
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STATISTICAL ANALYSIS OF REPAIR AND
MAINTENANCE OF INSTITUTE VEHICLES
A PROJECT REPORT
Prepared by
Pranoy Dutta (DIP/08/ME/012)
Render Sangma (DIP/08/ME/014)
Hage Momo (DIP/08/ME/016)
Ervin M. Sangma (DIP/08/ME/018)
Under the guidance of
Mr. C. M. Krishna
In partial fulfillment for the award of degree
of
CERTIFICATE OF DIPLOMA
IN
MECHANICAL ENGINEERING
NORTH EASTERN REGIONAL INSTITUTE OF SCIENCE AND
TECHNOLOGY(Deemed University u/s 3 of UGC Act 1956)
Nirjuli, Itanagar, Arunachal Pradesh 791109
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SIGNATURE
Mr. Sunirmal Ray
HEAD OF DEPARTMENT
Department of
Mechanical Engineering
NERIST
Nirjuli, Itanagar, Arunachal Pradesh - 791109
BONAFIDE CERTIFICATE
Certified that this project report titled Statistical Analysis Of Repair and Maintenance
of Institute Vehicles is the bonafide work of Pranoy Dutta (DIP/08/ME/012), Render
Sangma (DIP/08/ME014), Hage Momo (DIP/08/ME/016) and Ervin M. Sangma
(DIP/08/ME/018) who carried out the work under my supervision. Certified further,
that to the best of my knowledge the work reported herein does not form part of any
other project report or dissertation on the basis of which a degree or award was
conferred on an earlier occasion on this or any other candidate.
SIGNATURE
Mr. C. M. Krishna
PROJECT GUIDE
Asst. Professor,
Department of
Mechanical engineering
SIGNATURE
Mr. N. K. Rana
COURSE CO-ORDINATOR
Lecturer,
Department of
Mechanical Engineering
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Statistical Analysis of Repair and Maintenance of Institute Vehicles i
NERIST, Nirjuli, Arunachal Pradesh - 791109
CANDIDATES DECLARATION
This work is submitted for award of partial fulfillment of the degree of Certificate of
Diploma in Mechanical Engineering. All data, references and results as produced in the
dissertation are taken to be genuine and used for academic purpose only.
Pranoy Dutta Hage Momo
(DIP/08/ME/012) (Dip/08/ME/016)
Render Sangma Ervin M. Sangma
(DIP/08/ME/014) (DIP/08/ME/018)
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Statistical Analysis of Repair and Maintenance of Institute Vehicles ii
NERIST, Nirjuli, Arunachal Pradesh - 791109
ABSTRACT
The dissertation proceeds to bring to light the most general areas of breakdown of
vehicles under the possession of North Eastern Regional Institute. It may be upheld as a
simple manifestation of application of Statistical Process Control and affirmed as a step
towards the idea of improvement of the maintenance procedures carried out in the
institute. The work is entirely centered on the data corresponding to a sample of five
vehicles selected at random. Parameters effecting the operation of analysis have been
addressed. Implementation of results and evaluation of performance, however, are
beyond this work and have not been alluded hence. The tasks performed show gradual
development of a programme for assessment of maintenance procedures. It illustrates
use of checksheets, pareto charts, histograms and Ishikawa cause and effect diagrams in
the approach. A brainstorming session conducted to gain an idea behind the symptoms
and possible causes of the defects determined as critical can be taken to be the final
stage of the work and the other methods described in between.
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Statistical Analysis of Repair and Maintenance of Institute Vehicles iii
NERIST, Nirjuli, Arunachal Pradesh - 791109
ACKNOWLEDGEMENT
We are thankful to Mr. Sunirmal Ray (Head Of Department, Department of Mechanical
Engineering, NERIST) for presenting us with the opportunity to undertake this project
at the institution premises. We have also received assistance and ideas from Mr. N. K.
Rana (Course Co-ordinator of ME-4299). He generously shared his teaching
experiences and rendered insightful comments on the work. We express our sincere
thanks to our project guide Mr. C. M. Krishna (Asst. Professor, Department of
Mechanical Engineering, NERIST and Chairman, Transport Section) for lending us his
time and knowledge of statistics and quality. We are also thankful to him for directing
us towards such an interesting topic.
We are indebted to Mr. Toko Shama (Transport Officer, Transport Section, NERIST)
for helping us with our queries. We extend our heartfelt thanks to Mr. H. B. Chetri
(Transport Office) for his patience and willing approval to our requests throughout the
work transition. The team also appreciates the efforts of the drivers and a few other
people who have been an integral part of the project for their valuable support and co-
operation.
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Statistical Analysis of Repair and Maintenance of Institute Vehicles iv
NERIST, Nirjuli, Arunachal Pradesh - 791109
CONTENTS
Chapter Contents Page
Candidate's declaration iAbstract ii
Acknowledgement iii
1 Introduction 1
2 Concept of Quality 3
2.1 Introduction to Quality 3
2.2 Cost of Quality 5
2.3 Dimensions of Quality 6
2.4 A Brief History of Quality Control and Improvement 7
2.5 Statistical Methods for Quality Control and Improvement 7
2.6 Statistical Process Control 8
2.7 Sources of Variation 102.8 Statistical Process Control Tools 11
2.9 ISO in Quality Management System 19
3 Case Study 20
3.1 Defining Mission of Study and Approach 20
3.2 Data Ingestion 21
3.3 Analysis of Data 22
3.3.1 Classification of Data 22
3.3.2 Comparison of System-assemblies 24
3.3.3 Sub-systems Comprising Others 28
3.3.4 Sorting of Major Failures 30
3.3.5 Selecting Critical Defects 35
3.4 Brainstorming Causes of Defects 37
3.4.1 Kingpin 38
3.4.2 Self Starter Assembly 38
3.4.3 Brake Assembly 39
3.5 Conclusion 43
Appendix A - List of Vehicles in NERIST 44
Appendix B - Technical Specification of Samples 45
Appendix C - WinSTAT and Microsoft Excel 2003/2007 50
Appendix D - Glossary 53
References 55
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Statistical Analysis of Repair and Maintenance of Institute Vehicles v
NERIST, Nirjuli, Arunachal Pradesh - 791109
LIST OF FIGURES
Figure No. Caption Page No.
2.1 Sample process flowchart 12
2.2 Sample check sheet 132.3 Sample histogram 14
2.4 Sample pareto chart 14
2.5. Sample cause and effect or Fishbone diagram 15
2.6 Sample scatter diagram 16
2.7 Sample process control chart 17
3.1
Pareto chart of number of occurrences of
failures and system-assemblies for Maruti
Versa SDX
25
3.2
Pareto chart of number of occurrences of
failures and system-assemblies for Tata
Indigo GLX
25
3.3
Pareto chart of number of occurrences of
failures and system-assemblies for
Ambassador 1800 ISZ
26
3.4
Pareto chart of number of occurrences of
failures and system-assemblies for Tata
LP1210 bus (42 seats)
26
3.5
Pareto chart of number of occurrences of
failures and system-assemblies for Tata
LP1210 bus (62 seats)
27
3.6Occurrences of failures vs. system assemblies
of the five vehicles
27
3.7
Pareto Chart of number of occurrences of
failures and sub-classes of Others for Maruti
Versa SDX
30
3.8sSub-system 'Front axle and brakes' bar
diagram for Maruti Versa SDX
31
3.9
Pareto Chart of number of occurrences of
failures and sub-classes of Others for Tata
LP1210 bus (42 seats)
31
3.10Sub system 'Front axle and brakes' bar
diagram for Tata LP1210 bus (42 seats)
32
3.11
Pareto chart of number of occurrences of
failures and sub-classes of Others for Tata
Indigo GLX
32
3.12Sub class 'Support systems' bar diagram for
Tata Indigo GLX
33
3.13
Pareto chart of number of occurrences of
failures and sub-classes of Others for
Ambassador 1800 ISZ
33
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Statistical Analysis of Repair and Maintenance of Institute Vehicles vi
NERIST, Nirjuli, Arunachal Pradesh - 791109
3.14Sub class 'Support systems' bar diagram for
Ambassador 1800 ISZ
34
3.15
Pareto chart of number of occurrences of
failures and sub-classes of Others for Tata
LP1210 bus (62 seats)
34
3.16Sub class 'Support systems' bar diagram for
Tata LP1210 bus (62 seats)
35
3.17 King pin assembly 38
3.18 Self starter asembly 38
3.19a Disc brake 39
3.19b Drum brake 39
3.20 Fish bone diagram for kingpin defects 40
3.21 Fish bone diagram for self-starter defects 41
3.22 Fish bone diagram for brake assembly defects 42
LIST OF TABLES
3.1 Classification of system-assemblies 23
3.2 Primary failures in Engine, Transmission and Rear
axle classification
28
3.3 Sub-classification of others 29
3.4 Sorting of Critical defects with respect to both
frequency and cost.
36
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Statistical Analysis of Repair and Maintenance of Institute Vehicles 1
NERIST, Nirjuli, Arunachal Pradesh - 791109
CHAPTER 1
INTRODUCTION
The Statistical Analysis of Repair and Maintenance of Institute Vehicles is an
independent work drawn mainly on the data recorded in the Transport Section of North
Eastern Regional Institute of Science and Technology(NERIST). The Transport
Section, which is responsible for all the vehicles owned by the institute, is comprised of
the Automobile Workshop, the Stores and the Transport Office. The institute at present
has 14 four-wheelers under its possession of which two are unusable. The list is
provided in Appendix A. Of late, it has been found that vehicles are increasingly under
repair for defects developing primarily around a few components. As the financial
implications of these defects on the management are huge, it necessitates detailed study
of the types of defects and their frequency.
The vehicles under normal conditions run an average distance of 15 kilometres a day
being used mainly for staff and student services. The usage characteristic may rise up to
150-250 kilometres per day owing to carrying guests and invitees during celebrations
and events organized within the institute, while long distance journeys responding to
emergency situations and often requiring more than a day on the road beef up the daily
usage to above 600 kilometres for diesel transport and to above 800 kilometres for
petrol.
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Statistical Analysis of Repair and Maintenance of Institute Vehicles 2
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This report entails the application of the basics of Quality Control and Statistical
Process Control tools in analyzing the status of the maintenance operations performed
on the vehicles. Repair works pertinent to mainly replacement of components,
excluding the recurrent expenditures on fuel, engine-oil and coolant, during the period
from 1 January 2003 to 31 December 2009 for the following five vehicles describe the
sample size.
1. Maruti Versa SDX (Reg. No.: AR-01-A-8290)
2. Tata Indigo GLX (Reg. No.: AR-01-A-8291)
3. Hindustan Motors Ambassador (Reg. No.: AR-01-A-4887)
4. Tata Bus LPO 1210 , 62 seater (Reg. No.: ARC-1463)
5. Tata Bus LPO 1210 , 42 seater (Reg. No.: AR-01-3980)
The subsequent sections of this report will provide the procedural progress of the work
and the derived concluding remarks with prior overview of the concept of quality. As
an aid to proper judgement of the condition of the vehicle by narrowing the list of
components to be checked down to the most substantial ones, the regular maintenance
procedure will be boosted surfacing the most likely breakdown in a definite interval of
time. The determination of the critical and major failure prone components
presented at the end of this report however do not conclude the necessary phases of
subsequent similar undertakings for establishing an absolutely functional and controlled
maintenance process. The purpose of the project is to indicate the causes of defects initems catalogued as parts of the most rapidly degenerating system and sub-system
assemblies among the vehicles of NERIST thereby creating avenues for better quality
control.
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Statistical Analysis of Repair and Maintenance of Institute Vehicles 3
NERIST, Nirjuli, Arunachal Pradesh - 791109
CHAPTER 2
CONCEPT OF QUALITY
2.1 INTRODUCTION
The word quality is often used to signify excellence of a product or service. Quality
is defined simply as meeting the requirements of the customer. A customer is
anyone who is affected by the service, product, or process. Customers could be
External or Internal. External Customers include ultimate users (current and potential)
and also intermediate processors, as well as retailers, other customer who are not
purchasers but have some connection to the product, e.g., government regulatory
bodies, shareholders, suppliers, partners, investors, the media, and the general public.
External customers clearly are of primary importance.
Internal Customers include other divisions of a company that are provided with
information or components for an assembly and also departments or persons that
supply products to each other. Thus when a purchasing department receives a
specification from an engineering department for procurement, purchasing is an
internal customer of engineering. When the procurement is provided, then engineering
is the internal customer of purchasing. The external and internal customers are
sometimes called stakeholders.
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NERIST, Nirjuli, Arunachal Pradesh - 791109
The costs of quality are no different from any other costs in that, like the costs of
maintenance, design, sales, distribution, promotion, production, and other activities,
they can be budgeted, monitored and analyzed. Prevention of failure in any
transformation is possible only if the process definition, inputs and outputs are properly
documented and agreed. Quality costs include prevention costs (these are associated
with the design, implementation and maintenance of the quality management system),
appraisal costs (these costs are associated with the suppliers and customers evaluation
of purchased materials, processes, intermediates, product and services to assure
conformance with the specified requirements) and failure costs. Failure costs can be
further split into those resulting from internal and external failure. Internal failure costs
occur when products or services fail to reach designed standards and are detected
before transfer to the consumer takes place. External failure costs occur when productsor services fail to reach design quality standards and are not detected until after transfer
to the consumer. When the ability to produce a quality product or service acceptable to
the customer is low, the total direct quality costs are high and the failure costs
predominate. The indirect quality costs associated with customer dissatisfaction, and
loss of reputation or goodwill, are often intractable. In the services sector the combined
quality cost may be higher than 35% of the total gross revenue.
2.3 DIMENSIONS OF QUALITY
The quality of a product can be evaluated in several ways. Garvin (1987) provides an
excellent discussion of eight components or dimension of quality. These are mentioned
below:
a. Performance (will the product do the intended job?)
b. Reliability (how often does the product fail?)
c. Durability (how long does the product last?)d. Serviceability (how easy is it to repair the product?)
e. Aesthetics (what does the product look like?)
f. Features (what does the product do?)
g. Perceived Quality (what is the reputation of the company or its product?)
h. Conformance to standards (is the product made exactly as the designer
intended?)
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Statistical Analysis of Repair and Maintenance of Institute Vehicles 7
NERIST, Nirjuli, Arunachal Pradesh - 791109
2.4 A BRIEF HISTORY OF QUALITY CONTROL AND
IMPROVEMENT
Most of the statistical quality control techniques used now have been developed during
the last century. Many individuals, during the 20th
century, contributed to the body of
knowledge on achieving superior quality and five names deserve particular mention:
Joseph M. Juran, W. Edwards Deming, Armand V. Feigenbaum, Philip Crosby and
Kaoru Ishikawa. One of the most commonly used statistical tools, control charts, was
introduced by Dr. Walter Shewart in 1924 at Bell Laboratories. The acceptance
sampling techniques were developed by Dr. H. F. Dodge and H. G. Romig in 1928,
also at Bell Laboratories. The use of design of experiments developed by Dr. R. A.
Fisher in the U.K. began in the 1930s. The end of World War II saw increased interest
in quality, primarily among the industries in Japan, which were helped by Dr. Deming.
Industry in the 1980s also benefited from the contributions of Dr. Genichi Taguchi to
design of experiments, loss function, and robust design. The recent emphasis on
teamwork in design has produced concurrent engineering*. The standards for a quality
system, ISO 9000, were introduced in the early 1990s.
2.5 STATISTICAL METHODS FOR QUALITY CONTROL AND
IMPROVEMENT
Statistical Quality Control (SQC) is the term used to describe the set of statistical
tools used by quality professionals. SQC consists of three major areas:
a. Acceptance samplingb. Statistical process control
c. Design of experiments
Acceptance sampling: Acceptance sampling is the process of randomly inspecting
a sample of goods and deciding whether to accept the entire lot based on the results.
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Statistical Analysis of Repair and Maintenance of Institute Vehicles 8
NERIST, Nirjuli, Arunachal Pradesh - 791109
Acceptance sampling determines whether a batch of goods should be accepted or
rejected. The objective is not to control the quality of lots.
Statistical process control (SPC): It involves inspecting a random sample of the
output from a process and deciding whether the process is producing products with
characteristics that fall within a predetermined range. SPC answers the question of
whether the process is functioning properly or not.
Design of experiments: A design experiment is extremely helpful in discovering
the key variables influencing the quality characteristics of interest in the process. Adesigned experiment is an approach to systematically varying the controllable input
factors in the process and determining the effect these factors have on the output
product parameters. Statistically designed experiments are invaluable in reducing
the variability in the quality characteristics and in determining the levels o the
controllable variables that optimize process performance.
All three of these statistical quality control categories are helpful in measuring andevaluating the quality of products or services. However, statistical process control
(SPC) tools are used most frequently because they identify quality problems during the
production process and for general statistical analysis.
2.6 STATISTICAL PROCESS CONTROL
Statistics is the language in which development engineers, manufacturing, procurement,
management, and other functional components of the business communicate about
quality. Statistical methods provide the principal means by which a product is sampled,
tested and evaluated. There have been many successful applications of statistical
process control methods in the manufacturing environment. However, the principles
themselves are general; consequently, there are many non-industrial or service industry
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Statistical Analysis of Repair and Maintenance of Institute Vehicles 10
NERIST, Nirjuli, Arunachal Pradesh - 791109
affect product and service outcomes, and one challenge is to focus on the processes and
variables that are of key concern. SPC tools can be useful in identifying areas that need
attention, but managerial insight is needed to use the SPC tools strategically.
2.7 SOURCES OF VARIATION: COMMON AND ASSIGNABLE
CAUSES
In any production process, regardless of how well designed or carefully maintained it is
a certain amount of inherent or natural variability will always exist. This natural
variability or background noise is the cumulative effect of many small, essentially
unavoidable causes. In the framework of statistical quality control, this natural
variability is often called a stable system of chance causes. A process operating with
only chance causes of variation, also known as Random causes or Common causes, is
said to be in statistical control. In other words, the chance causes are an inherent part of
the process.
Other kinds of variability may occasionally be present in the output of a process. Thisvariability in key quality characteristics usually arises from three sources: improperly
adjusted or controlled machines, operator machines, or defective raw material. Such
variability is generally large when compared to the background noise, and it usually
represents an unacceptable level of process performance. We refer to these sources of
variability that are not part of the chance cause pattern as assignable causes. A
process that is operating in the presence of assignable causes is said to be out of
control.
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Statistical Analysis of Repair and Maintenance of Institute Vehicles 11
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2.8 STATISTICAL PROCESS CONTROL TOOLS
In Statistical Process Control numbers and information will form the basis for decisions
and actions, and a thorough data recording system is essential. In addition to the basic
elements of a management system, which will provide a framework for recording data,
there exists a set of tools which may be applied to interpret fully and derive maximum
use of the data. The simple methods listed below will offer any organization a means of
collecting, presenting and analyzing most of its data:
a. Process flowchart what is done?
b. Check sheet / tally chart how often is it done?
c. Histogram what does the variation look like?d. Pareto chart which are the big problems?
e. Cause and effect diagram what causes the problems?
f. Defect concentration diagram what does the location of the defect signify?
g. Scatter diagram what are the relationships between factors?
h. Control chart which variations to control and how?
Process flowchart: Flowcharts are frequently used to communicate the components of
a system or process to others whose skills and knowledge are needed in the
improvement effort. Therefore, the use of standard symbols is necessary to remove any
barrier to understanding or communication.
The purpose of the flowchart analysis is to learn why the current system/process
operates in the manner it does, and to prepare a method for objective analysis. The team
using the flowchart should analyze and document their findings to identify:
The problems and weaknesses in the current process system.
Unnecessary steps or duplication of effort.
The objectives of the improvement effort.
The flowchart techniques can also be used to study a simple system and how it would
look if there were no problems. This method has been called imagineering and is a
useful aid to visualizing the improvements required. The flowchart below demonstrates
part of a contact lens conversion process.
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Stati
NERIST, Nirjuli, Arunachal
Check sheet: In early st
to collect either histor
investigation. A check s
marks and frequency disdesigning a check shee
collected, the part or ope
useful in diagnosing the
stical Analysis of Repair and Maintenance of Instit
Pradesh - 791109
Fig. 2.1 Sample process flow chart
ges of an SPC implementation, it will often be
ical or current operating data about the
heet can be very useful in this data collection
tribution tables could prove helpful in such ait is important to clearly specify the type
ation number, the date, the analyst, and any ot
ause of poor performance.
ute Vehicles 12
ome necessary
process under
activity. Tally
proach. Whenof data to be
er information
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Statistical Analysis of Repair and Maintenance of Institute Vehicles 13
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Fig. 2.2 Sample Check sheet
Histograms: A histogram is the variation of a product or the results of a process. It
often forms the bell-shaped curve which is characteristic of a normal process. Thehistogram helps you analyze what is going on in the process and helps show the
capability of a process, whether the data is falling inside the bell-shaped curve and
within specifications. A histogram displays a frequency distribution of the occurrence
of the various measurements. The variable being measured is along the horizontal x-
axis, and is grouped into a range of measurements. The frequency of occurrence of each
measurement is charted along the vertical y-axis. Histograms depict the central
tendency or mean of the data, and its variation or spread. A histogram also shows the
range of measurements, which defines the process capability.
Pareto chart: Pareto charts are graphical demonstrations of occurrences, with the most
frequently occurring event to the left and less frequent occurrences to the right. It is a
graph displaying rank in descending order of importance for the categories of problems,
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Stati
NERIST, Nirjuli, Arunachal
defects or opportunities.
first by showing the pro
comprise. This is based
problem.
stical Analysis of Repair and Maintenance of Instit
Pradesh - 791109
Fig. 2.4 Sample Pareto Chart
A Pareto chart or diagram indicates which pr
ortion of the total problem that each of the s
n the Pareto principle: 20% of the sources ca
Fig. 2.3 Sample histogram
ute Vehicles 14
blem to tackle
aller problems
se 80% of the
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Stati
NERIST, Nirjuli, Arunachal
Ishikawa Cause and e
causes of quality proble
and the bones of the fish
to the left. Potential ca
environment, and mana
Useful in brainstorming
multiple perspectives, th
When completed, further
Ishikawa diagram.
Fig. 2.5 Samp
stical Analysis of Repair and Maintenance of Instit
Pradesh - 791109
ffect diagram: These diagrams depict an arr
s. The problem (the head of the fish) is display
representing the potential causes of the probl
uses are often categorized as materials, equi
gement. Other categories may be included
the causes of problems (including potential p
se diagrams should include all possible reasons
analysis is done to identify the root cause. Fig
le Cause and Effect diagram or Fishbone diag
ute Vehicles 15
y of potential
ed on the right,
mare drawn
ment, people,
s appropriate.
roblems) from
for a problem.
re below is an
am
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Statistical Analysis of Repair and Maintenance of Institute Vehicles 16
NERIST, Nirjuli, Arunachal Pradesh - 791109
Defect concentration diagram: A defect concentration diagram is a picture of the unit,
showing all relevant views. Then the various types of defects are drawn on the picture,
and the diagram is analyzed to determine whether the location of the defects on the unit
conveys any useful information about the potential causes of the defects.
Scatter diagram: Scatter plots are also called correlation charts. A Scatter plot is used
to uncover possible cause-and-effect relationships. It is constructed by plotting two
variables against one another on a pair of axes. A Scatter plot cannot prove that one
variable causes another, but it does show how a pair of variables is related and the
strength of that relationship. Statistical tests quantify the degree of correlation between
the variables.
Fig. 2.6 Sample Scatter diagram
Control Charts: Statistical Process Control charts graphically represent the variability
in a process over time. When used to monitor the process, control charts can uncover
inconsistencies and unnatural fluctuations. Consequently, SPC charts are used in many
industries to improve quality and reduce costs. Statistical control does not imply zero
variationsome degree of variation is normal and it is unrealistic to expect zero
variation Control charts typically display the limits that statistical variability can
explain as normal. If your process is performing within these limits, it is said to be in
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Statistical Analysis of Repair and Maintenance of Institute Vehicles 17
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control; if not, it is out of control. Control does not necessarily mean that a product or
service is meeting your needs; it only means that the process is behaving consistently.
The most commonly employed control charts are the mean chart and the range chart,
often referred to as X-bar and R-charts.
Control limits are calculated statistically from your data. They are referred to as the
Lower Control Limit (LCL) and the Upper Control Limit (UCL) on a control chart.
These are set at 3-sigma by default since this is the most commonly used limit. Control
limits define the zone where the observed data for a stable and consistent process
occurs virtually all of the time (99.7%). Any fluctuations within these limits come from
common causes inherent to the system, such as choice of equipment, scheduledmaintenance or the precision of the operation that results from the design. These normal
fluctuations are attributed to statistical variability. An outcome beyond the control
limits results from a special cause. Special causes are events external to the ordinary
operation of a production or service.
Fig. 2.7 Sample Process Control chart
Control charts are divided into two groups:
Variable Data
Variable charts are based on variable data that can be measured on a continuous scale.
For example, weight, volume, temperature or length of stay. These can be measured to
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as many decimal places as necessary. Individual, average and range charts are used for
variable data.
Attribute Data
Attribute charts are based on data that can be grouped and counted as present or not.
Attribute charts are also called count charts and attribute data is also known as discrete
data. Attribute data is measured only with whole numbers. Examples include:
Acceptable vs. non-acceptable
Forms completed with errors vs. without errors
Number of prescriptions with errors vs. without
When constructing attribute control charts, a subgroup is the group of units that were
inspected to obtain the number of defects or the number of defective items. Defect and
reject charts are used for attribute data.
Statistical Process Control (SPC) Charts are essentially:
Simple graphical tools that enable process performance monitoring
Designed to identify which type of variation exist within the process
Designed to highlight areas that may require further investigation
Easy to construct and interpret
Thus, Statistical Process Control is a set of tools for managing processes, and
determining and monitoring the quality of the outputs of an organization. It is also a
strategy for reducing variation in products, deliveries, processes, materials, attitudes,
and equipment. The question which needs to be asked continually is Could we do the
job better?
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2.9 ISO IN QUALITY MANAGEMENT SYSTEM
The International Organization for Standardization (ISO) series programme provides
standards for data documentation and audits as part of a quality management system.
The ISO was developed in Europe but was influenced in the second half of the
twentieth century by U.S. military standards. ISO standards for documenting business
practices, including ISO 9000: 1994 and ISO 9000: 2000 document series aimed to
reduce variation in production. The ISO 9000 series should be viewed as the minimum
elements of a quality system. The emphasis in ISO is not on results but on the existence
and conformance to the elements of a quality system. The automotive industry has its
own definition of the elements of a quality system, i.e. QS 9000. QS 9000 includes ISO
9000 requirements but incorporates additional quality system elements required by the
automotive industry, e.g. process capability and process performance requirements. A
few of the specific standards for Quality Management Systems are cited here:
ISO 9004-1: General quality guidelines to implement a quality system.
ISO 9004-4: Guidelines for implementing continuous quality improvement
within the organization, using tools and techniques based on data collection and
analysis.
ISO 10005: Guidance on how to prepare quality plans for the control of specific
projects.
ISO 10011-1: Guidelines for auditing a quality system. ISO 10011-2: Guidance on the qualification criteria for quality systems
auditors.
ISO 10011-3: Guidelines for managing quality system audit programmes.
ISO 10012: Guidelines on calibration systems and statistical controls to ensure
that measurements are made with the intended accuracy.
ISO 10013: Guidelines for developing quality manuals to meet specific needs.
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CHAPTER 3
CASE STUDY
3.1 DEFINING MISSION OF THE STUDY AND APPROACH
For the large fleet of vehicles owned by NERIST, the institution incurs huge expenses
due to the performance of frequent maintenance operations. The project perceived on
the basis of the fast degrading conditions of the vehicles is sought to be generative
towards a possible pattern for the use of vehicles as under the supervision of theauthorized personnel of the Transport Section.
The approach to the problem is a data-driven approach. The goal is to present a
simplified maintenance process and as such data-driven analysis has not been carried
out independently with the classification whether the engines run on gasoline or diesel,
in view. It has been generalized from the very start of collection of data, although the
vehicles are easily identifiable to proceed with an independent course of analysis.
The few components intercepted for analysis confirming the most potential causes of
defects in the vehicles, in general, constitutes the first phase of the work. The sources
tending to affect conversely the performance of all the components discussed during
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sorting of the minor, major and critical defects have not been evaluated; it is integral to
complete the pattern identification of maintenance control to continue with the analysis
of rest of the components, preferably anew, once the current roots-causes have been
overcome.
The display of analysis results is intuitively interpretable to all who possess the
fundamental concept of statistics. All steps have been delineated in the corresponding
section of the report for further verification if necessary.
The chart designs have been created with Microsoft Excel, a mathematical packagegood for working with absolute and dynamic tables. For rapid development of charts,
WinSTAT, a plug-in compatible with Microsoft Excel 2003/2007, was used. A detailed
step-wise procedure to use WinSTAT has been attached to the end of the report.
3.2 DATA INGESTION
The Transport Office maintains separate record for each vehicle regarding the purchase
of new components, replacement of parts, all minor and major adjustments and
maintenance by external operators. The data gathered for study is based solely on these
records.
The vehicles viz. Maruti Versa SDX, Tata Indigo GLX, Hindustan Motors Ambassador
ISZ 1800 and Tata bus LP 1210 (42 and 62 seats),were selected to represent and build a
database of rich variant of defects. The technical specifications of the five vehicles have
been given in Appendix B. The dates of purchase and manufacture of the vehicles
differ by considerable intervals and their present conditions as well. The 62 passenger
seat bus is now condemned. It is crucial to consider a period for the operable condition
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Statistical Analysis of Repair and Maintenance of Institute Vehicles 22
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of the vehicles for the study. The data, therefore, is confined to the period from 1st
of
January, 2003 to 31st
of December, 2009.
A few other considerations as incorporated during the collection of data are mentioned
in the following:
1. All jobs related to replacement of parts have been neglected. This is because the
purchase of parts and their replacement would unnecessarily double the number
of occurrences; hence the jobs have been conveniently left out.
2. A few components have been excepted as the expense assessed on each unit is
minimal. These mainly include washers, small bolts, bushes, springs, clips and
tyre repairs.
3. The recurring expenditures on engine-oil, coolant, grease, brake-fluid and gear-
oil are regarded expendable since these already form a part of standard
maintenance procedure.
The effort has been to concentrate mainly on technical failures. These failures as found
and documented make up the variables of study at this point.
3.3 ANALYSIS OF DATA
The data obtained for each vehicle had to be transformed into Check sheets as a
catalogue of parts-replaced against the number of times replaced. The total cost for
each component was also duly noted.
3.3.1 Classification of Data
The failures were broadly classified into four groups for each of the vehicles as given
here:
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1. Engine assembly
2. Transmission system
3. Rear axle assembly
4. Others (comprising the rest)
The various sub-systems that make up the above major groups are given in table-3.1
below.
Table 3.1 Classification of system-assemblies
Sl.
No. Group Sub-systems
1 Engine assembly Engine
Valve mechanism
Timing mechanismPiston
Cylinder
Fuel system
Fuel injection pump
Fuel transfer pump
Fuel injectors
Fuel filters
Fuel lines
Intake system
Air filter
Turbo charger
Intercooler
Air filter clogging indicator
Hoses
Exhaust system
Silencer/Muffler/Expansion
Chamber
Catalytic converter
Oxygen sensor (Petrol vehicles)
Cooling system
Water pump
Thermostat
Cooling fan
Oil Cooler
Radiator
Radiator Pressure Cap
Coolant Recovery Tank
Drive belts
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2 Transmission system Clutch
Actuating mechanism
Cable
Master cylinderSlave cylinder
Pressure plate
Gear box
Gear change mechanism
Synchroniser mechanism
Transfer case
Propeller shaft
Differential pinion
3 Rear Axle assembly
Rear brakes
G-valve
Wheel brakes
Axle shafts
Differential
Differential Gears
Crown wheel
Wheels
Wheel spindle
Wheel bearings
Rear suspensionSprings
Shock absorber
Stabilizer bar
4 Others Comprising the rest
3.3.2 Comparison of system-assemblies
Taking help of Pareto Charts
To distinguish the group with the highest number of defects, Pareto charts were plotted
for each of the vehicles. Figures (3.1) to (3.5) demonstrate the relationship of various
system groups with the corresponding number of failures under them.
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Fig (3.1): Pareto Chart of number of occurrences of failures and system-assemblies
for Maruti Versa SDX
Fig (3.2): Pareto Chart of number of occurrences of failures and system-assemblies
for Tata Indigo GLX
63
10
61
78.75
91.25
98.75 100.00
0.00
20.00
40.00
60.00
80.00
100.00
0
10
20
30
40
50
60
70
80
Others Rear axle Engine Transmission
Frequency cumulative (%)
4542
21
4
40.18
77.68
96.43 100.00
0.00
20.00
40.00
60.00
80.00
100.00
0
10
20
30
40
50
60
70
80
90
100
110
Others Engine Rear axle Transmission
Frequency cumulative (%)
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Fig (3.3): Pareto Chart of number of occurrences of failures and system-assemblies
for Hindustan Ambassador ISZ 1800
Fig (3.4): Pareto Chart of number of occurrences of failures and system-assemblies
for Tata bus LP 1210 (42 seats)
65
30
20 18
48.87
71.43
86.47
100.00
0.00
20.00
40.00
60.00
80.00
100.00
0
10
20
30
40
50
60
70
80
90
100
110
120
130
Others Rear axle Engine Transmission
Frequency cumulative (%)
128
44 4033
52.24
70.20
86.53
100.00
0.00
20.00
40.00
60.00
80.00
100.00
0
20
40
60
80
100
120
140
160
180
200
220
240
Others Transmission Engine Rear Axle
Frequency cumulative (%)
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Fig (3.5): Pareto Chart of number of occurrences of failures and system-assemblies
for Tata bus LP 1210 (62 seats)
The combined comparative representation for all the sample vehicles together is
displayed with the help of histogram in figure (3.6).
Figure (3.6): Occurrences of failures vs. system assemblies of the five vehicles.
62
28 26
10
49.21
71.43
92.06
100.00
0.00
20.00
40.00
60.00
80.00
100.00
0
10
20
30
40
50
60
70
80
90
100
110
120
Others Engine Rear Axle Transmission
Frequency cumulative (%)
6
42
20
40
28
14
18
44
1010
21
3033
26
63
45
65
128
62
0
20
40
60
80
100
120
140
Maruti Versa
SDX
Tata Indigo GLX Ambassador
1800 ISZ
Tata Bus LP 1210
(45 seater)
Tata Bus LP 1210
(62 seater)
Engine
Transmission
Rear axle
Others
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The number of failures detected under each of the engine, the transmission and the rear-
axle assemblies is evidently less than the rest of the failures together grouped under
Others for all the cases. A further macro-level analysis to assess the arbitrary failures
as included under Others is detailed in the next section. The varying features of the
charts corresponding to different vehicles may be illustrated on the basis of period of
use, conditions of driving, maintenance procedures followed and, the quality and
performance reputation of the brand and model. A few of the major failures noted
under the other three assembly-groups as regards both frequency and cost are given in
table 3.2 below.
Table: 3.2 Primary failures in Engine, Transmission and Rear axle classification
Group Failures/Defects
Engine Both by cost and frequency Silencer Assembly
Timing belt
By cost Radiator fan & motor
Transmission Both by cost and frequency Centre bearing
Universal Joint spider
By cost Differential pinion
Rear axle Both by cost and frequency Strut assembly
Wheel Cylinder Assembly
By cost Shock absorber
Rear axle bearing
3.3.3 Sub-systems comprising Others
All remaining systems and sub-systems, besides those specifically provided in table-
3.1, have been included in Others. This has been further sub-classified into four more
categories. These are:
1. Steering system
2. Front axle and brakes
3. Heating, Ventilation and Cooling (HVAC) system
4. Remaining support systems
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The class of component-failures making up the main classification is better explored
with the help of table (3.3)
Table 3.3 Sub-classification of 'Others'
Sl.
No. Sub-group Components
1 Steering system Gear box
Steering wheel
Steering inner/outer columns
Tie rods
Power steering pump
Power steering reservoir
Hoses
2 Front Axle and Brakes SpringsShock absorber
Stabilizer bar
Tandem master cylinder
Vacuum pump
Wheel brakes
Brake fluid reservoir
Axle shafts
Wheel bearings
3 Heating, Ventilation & Cooling system Condenser
Blower
Heater
Evaporator
Compressor
Thermistor
Thermo amplifier
4 Remaining support systems Alternator
Battery
Wiring harness, fuses, relays, switches
Generator
Lighting system
Windshield wiper systemDoor locking systems
Window operating systems
It is, therefore, seen that the sub-classification consists of the entire steering system
adopting any of the steering gear box mechanism such as rack and pinion or re-
circulating ball type along with power steering arrangement, the suspension system at
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the front, the front brake assembly and also the central hydraulic brake components
(excepted in the Rear axle assembly earlier) such as the tandem master cylinder and the
fluid reservoir, the cabin climatic condition control system, the electrical instruments
and the body.
3.3.4 Sorting of Major Failures
The major failures for all sample vehicles were examined with the development of
Pareto charts depending on their frequency in each of the sub-classes of Others as
elucidated in the undermentioned figures. A vehicle-wise interpretation of the results is
provided here.
Maruti Versa SDX
Fig.3.7 Pareto Chart of number of occurrences of failures and sub-classes of Others
for Maruti Versa SDX
The front axle and brake assembly, demonstrating the highest frequency, is properly
accounted as the major failure prone class of components in Versa. A component-wise
study reveals that the Joint Stabilizer and the Suspension-arm assembly are the most
common factors of lapse in vehicle performance, as denoted by fig. (3.8).
38
20
6
0
60.32
92.06
100.00 100.00
0.00
20.00
40.00
60.00
80.00
100.00
0
10
20
30
40
50
60
Axle(F) & brake Support systems Steering Heating, Cooling &ventilation
Frequency cumulative (%)
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Fig. 3.8 Sub system 'Front axle and brakes' bar diagram for Maruti Versa SDX
Tata LP 1210 bus (42 seats)
The front-axle & brake assembly is also obtained as the major failure prone class of
components for Tata LP1210 bus (42 seats) described in figures (3.9) and (3.10).
Fig. 3.9 Pareto Chart of number of occurrences of failures and sub-classes of Others
for Tata LP1210 bus (42 seats)
Unlike the Versa SDX, the component-wise distribution in this case indicates that
front-wheel oil seal and wheel cylinder kit need to be paid substantial attention. The
HVAC is ruled out from failures because of absence of the system in the vehicle.
7
6
5 5
4
22 2
2 1 1 1
0
1
2
3
4
5
6
7
8
Series1
5952
17
0
46.09
86.72
100.00 100.00
0.00
20.00
40.00
60.00
80.00
100.00
0
20
40
60
80
100
120
Axle(F) & brake Support systems Steering Heating, Cooling &ventilation
Frequency cumulative (%)
N
o.
offailures
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Fig. 3.10 Sub system 'Front axle and brakes' bar diagram for Tata LP1210 bus (42seats)
Tata Indigo GLX
The subsequent figures put the sub-category of Remaining Support Systems
consistently as the major class of defaults with Headlamps as the critical defect. This is
well understood from the pareto charts of the remaining sample vehicles.
Fig. 3.11 Pareto Chart of number of occurrences of failures and sub-classes of Others
for Tata Indigo GLX
8
7
5
4 4 4
3 3 3
2 2 2 2 2
1 1 1 1 1 1 1 1
0
1
2
3
4
5
6
7
8
9
Series1
22
14
6
3
48.89
80.00
93.33100.00
0.00
20.00
40.00
60.00
80.00
100.00
0
10
20
30
40
Support systems Steering Axle(F) & brake Heating, Cooling &ventilation
Frequency cumulative (%)
No.
offa
ilures
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Fig. 3.12 Sub-class Support systems' bar diagram for Tata Indigo GLX
Hindustan Motors Ambassador 1800 ISZ
Fig. 3.13 Pareto Chart of number of occurrences of failures and sub-classes of Others
for Hindustan Motors Ambassador 1800 ISZ
5
3
2 2 2
1 1 1 1 1 1 1 1
0
1
2
3
4
5
6
Series1
37
16
11
1
56.92
81.54
98.46 100.00
0.00
20.00
40.00
60.00
80.00
100.00
0
10
20
30
40
50
60
Support systems Axle(F) & brake Steering Heating, Cooling &ventilation
Frequency cumulative (%)
No.
offailures
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Fig. 3.14 Sub-class Support systems' bar diagram for Hindustan Motors 1800 ISZ
Tata bus LP1210 (62 seats)
Fig. 3.15 Pareto Chart of number of occurrences of failures and sub-classes of Others
for Tata bus LP1210 (62 seats)
9
3 3 3 3
2 2
1 1 1 1 1 1 1 1 1 1 1 1
0
1
2
3
4
5
6
7
8
9
10
Series1
32
24
6
0
51.61
90.32100.00 100.00
0.00
20.00
40.00
60.00
80.00
100.00
0
10
20
30
40
50
60
Support systems Axle(F) & brake Steering Heating, Cooling &ventilation
Frequency cumulative (%)
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Fig. 3.16 Sub-class Support systems' bar diagram for Tata bus LP1210 (62 seats)
3.3.5 Selecting Critical Defects
Based on the above charts, a lot of components may be identified as deserving crucial
attention regarding improvement of maintenance process. Nevertheless the study has so
far been based on the number of occurrences of failures in these components alone. It is
desirable to work out failures which may be simultaneously cost-effective. Hence a
comparative study concerning both frequency and cost of failure has been shown in
table-4.4. It is to be noted that the joint-stabilizer comprises of both joint-stabilizer bar
and bush. Similarly, the door comprises of door lock, pad and handle.
9
3 3 3
2 2 2 2
1 1 1 1 1 1
0
1
2
3
4
5
6
7
8
9
10
Series1
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Table-3.4 Sorting of critical defects with respect to both frequency and cost.
The components in the above table have been sorted in descending order of their
frequency. The costs do not decrease correspondingly hinting at the fact that a few parts
are particularly expensive. These components may be called as High Cost components
while others may be called as Medium Cost or Low Cost components.
Table 3.4 thus gives headlamps, door, fog lamps, strut assembly, suspension assembly,
wheel cylinder and joint stabilizer as the critical defects. The cost-value of front wheel
oil seal per repair is low and hence may be assumed manageable. A brainstorming
activity over the reasons behind critical failures is indispensable for practical
implementation of the results.
Defect Versa
SDX
Indigo
GLX
Ambassador
ISZ
Bus 45-
seats
Bus 62
seats
Total
N=frequency N1 Cost N2 Cost N3 Cost N4 Cost N5 Cost N6 Cost
Headlamps 4 475.00 5 655.00 3 640.00 13 3929.00 9 2342.00 34 8041.0
Door 7 11647.00 1 185.00 9 3810.00 2 245.00 0 0.00 19 15887.0
Front wheel oil
seal 0 0.00 0 0.00 0 0.00 8 865.00 2 210.00 10 1075.0
Foglamps 2 2423.00 3 2050.00 3 2200.00 2 300.00 0 0.00 10 6973.0
Kingpin 0 0.00 0 0.00 0 0.00 5 5842.00 5 2756.00 10 8598.0
Joint Stabilizer 7 2299.00 0 0.00 2 675.00 0 0.00 0 0.00 9 2974.0
Wheel cylinder 0 0.00 0 0.00 1 240.00 7 1702.00 1 1680.00 9 3622.0
Suspension arm
assembly 6 4484.00 1 454.00 0 0.00 0 0.00 0 0.00 7 4938.0
Strut assembly 5 15020.00 1 2832.00 0 0.00 0 0.00 0 0.00 6 17852.0
Self - starter 0 0.00 1 200.00 0 0.00 3 949.00 1 9717.00 5 10866.0
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3.4 BRAINSTORMING CAUSES OF DEFECTS
What may be termed as Measure Phase in a quality improvement process, this stage is
defined by the identification of key parameters and process characteristics affecting the
occurrence of failures and measures the current control process capability. The
documentation of the project in terms of defects invariably draws the need to know the
pertinent causes as well. Multiple causes are common, in which case they follow the
Pareto principle; i.e., the vital few causes will dominate the rest. The diagnosis
(progress from symptom to cause) is studied in three steps:
Studying the symptoms surrounding the defects as a basis for theorizing about
causes. Theorize on the causes of these symptoms.
Collect and analyze data to test the theories and thereby determine the causes.
This has been satisfactorily applied in description of symptoms responsible for a few
major defects determined earlier. The various symptoms may be conveniently arranged
with respect to the following:
a. Man
b. Machine or material
c. Method
d. Environment
Man helps relate the driving practices and repair procedures to the component
failures, while machine/material specifies the availability and quality of components
required or used for repair. Method includes the maintenance and measurement
processes and, environment corresponds to the effects of natural conditions that result
in the constant growth of defects. These four areas were extensively studied for the
critical defects already recognized. A brainstorming session as undertaken with the co-
operation of the drivers employed by the institute authority together with the Transport
Officer facilitated assigning potential causes behind the selected breakdowns. The
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Stati
NERIST, Nirjuli, Arunachal
process has been illustrat
in the diesel-run buses), s
3.4.1 Kingpin
The kingpin is the m
mechanism of a car or o
was literally a steel pi
steerable wheel was mo
limits the degree of free
the front suspension. Kin
advantage of being able t
The results and validati
(3.20) with the help of Is
3.4.2 Self Starter As
An automotive start
commonly automobi
starter, or simply "start
is an electric motor nee
over the engine before it
itself. Car starters engage
connects to the battery t
there is a short in the
starter to receive a curren
have a solenoid attache
stical Analysis of Repair and Maintenance of Instit
Pradesh - 791109
ed in the following for three components viz. k
elf-starter and braking assembly.
ain pivot in the steering
ther vehicle. Originally this
on which the moveable,
unted to the suspension. It
om of motion of the rest of
gpins in suspension have the
o carry much heavier weights.
n of the causes for breakdown of kingpin is
ikawa cause and effect diagram.
embly
r motor,
ile self-
er motor",
ed to turn
can power
when you turn the key in the ignition mechani
o operate once the key is turned in the igniti
iring that connects these components, which
t from the battery even if the ignition is turned
d to the starter. Specifically, a lever from t
Fig. 3.17
Fig. 3.18 Self starter assem
ute Vehicles 38
ingpin (critical
shown figure
sm. The starter
on. Sometimes
can cause the
off. Some cars
he solenoid is
ingpin assembly
bly
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Stati
NERIST, Nirjuli, Arunachal
connected to the starter's
long enough to turn the fl
The results and validatio
(3.21) with the help of Is
3.4.3 Brake assembl
The modern automotiverefined for over 100
extremely dependable a
brake system consists o
either disk or drum-brake
a system of tubes and h
each wheel to the maste
that are connected with
booster and the anti-lock
On a disc brake, the flui
forced into a caliper whe
The piston in-turn sque
the disk (rotor) which
forcing it to slow down
fluid is forced into the
friction linings are presse
wheel to stop.
stical Analysis of Repair and Maintenance of Instit
Pradesh - 791109
clutch and pinion assembly. A starter is meant
ywheel and crank the engine.
n of the causes for breakdown of self-starter i
ikawa cause and effect diagram.
brake system has beenyears and has become
nd efficient. The typical
disk brakes in front and
s in the rear connected by
ses that link the brake at
cylinder. Other systems
the brake system include the parking brakes
system.
from the master cylinder is
re it presses against a piston.
zes two brake-pads against
is attached to the wheel,
or stop. With drum brakes,
heel cylinder, which pushes the brake shoes
d against the drum, which is attached to the wh
Fig. 3.19a Dis
Fig. 3.19b Dru
ute Vehicles 39
to engage only
s shown figure
, power brake-
out so that the
el, causing the
c brake
brake
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In either case, the friction surfaces of the pads on a disc brake system or the shoes on a
drum brake convert the forward motion of the vehicle into heat. Heat is what causes the
friction surfaces (linings) of the pads and shoes to eventually wear out and require
replacement.
The results and validation of the causes for breakdown of brake assembly is shown
figure (3.22) with the help of Ishikawa cause and effect diagram.
Fig. 3.20 Fish bone diagram for
Kingpin defects
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Fig. 3.21 Fish bone diagram for
Self starter assembly defects
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Fig. 3.22 Fish bone diagram for
brake assembly defects
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3.5 CONCLUSION
We describe this work as a demonstration of gradual progress of improvement of
quality control in general spheres and a careful implementation may require further
analysis and verification. What this project does is provide the basics of process control
and defines the relationships between the various components studied and the general
factors affecting their performance. A general implication of the project may be cited as
being directive towards better comprehension of the frequent need of repair works
carried out on the vehicles.
The work, in all aspects, may be sought to present the ideas at macro-level form of
analysis only. It is therefore desirable to extend the work with further assessment.
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APPENDIX A
LIST OF VEHICLES IN NERIST
1. Tata Bus LP 1210 (45 seat), AR-01-3980
2. Tata Bus (27 seat), ARC-2356
3. Tata Bus LP 1210 (62 seat), ARC-1463 (off-road)
4. Tata Winger (15 seat), AR-01-C-7303
5. Tata Mobile, AR-01-4598
6. Mahindra Scorpio VLX 7star, AR-01-C-4964
7. Hindustan Motors Ambassador 1800 ISZ, AR-01-4887
8. Maruti Gypsy IMG, AR-01-4600
9. Maruti Gypsy, AR-01-C-7523
10. Maruti Versa SDX, AR-01-A-8290
11. Tata Indigo GLX, AR-01-8291
12. Tata Sierra, AR-01-A-5281 (condemned)
13. Maruti Omni (Ambulance), AR-01-5286
14. Star Bus (54 seat), AR-01-C-4865)
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APPENDIX B
TECHNICAL SPECIFICATIONS OF SAMPLE VEHICLES
Maruti Versa SDX
Name of the supplier with address M/S Buishi Yada Motors, A-Sector, Naharlagun,
Arunachal Pradesh - 701110
Name of vehicle manufacturer Maruti Udyod Ltd.
Name of Authorized dealer M/S Buishi Yada Motors, A-Sector, Naharlagun,
Arunachal Pradesh - 701110
Vehicle Registration Number AR-01-A-8290
Model no.: Versa SDX; Colour: Starlite silver; Body:
Saloon
Date of delivery 28-02-2003
Price Rs. 5,39,493.00Year of manufacture 2003
Engine Fuel: Petrol; Cylinder: 4; Capacity: 1298 CC; Power:
82 bhp @ 6000 rpm
Gear box Manual 5 forward all synchromesh, 1 rear
Seating capacity 6 passenger seats + 1 driver
Brakes Fluid SAE J1703 or DOT; Disc brake
Steering Electronic Power Steering
Spark Plug NGK-BKR6E, Champion - RC 8YL, MICO - FR6DC4
Battery 12 V, 36 Amp hr
Fuses 12 V
Fuel tank 40 L
Engine sump 5 L
Coolant 5.3 L
Gear box 1.3 L
Rear axle 1.3 L
Gross weight 1500 kg
Tata Indigo GLX
Name of the supplier with address M/S Abhishek Motors Pvt. Ltd., G.N.B. Road,
Guwahati - 781003Name of vehicle manufacturer Tata Engineering & Locomotives Co. Ltd.
Name of Authorized dealer M/S Abhishek Motors Pvt. Ltd., G.N.B. Road,
Guwahati - 781003
Vehicle Registration Number AR-01-A-8291
Model: Indigo GLX, 475 SI MPFI; Colour: Meadow
Green; Body: Saloon
Date of delivery 26-03-2003
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Price Rs. 4,87,020.00
Year of manufacture 2003
Engine Fuel: Petrol; Cylinder: 4 inline; Capacity: 1405 CC;
Power: 62.3 KW or 85 ps at 5500 rpm
Gear box Synchromesh on all forward gears, sliding mesh for
reverse gear; model: TA65-5/3 42
Spring & suspension Front: Independent, lower wish bone Mc pherson
strut
Rear: Independent, 3 links and Mc pherson Strut
type; antiroll front and rear
Brakes Service brakes: Dual circuit, diagonal split hydraulic
brakes through Tandem Master cylinder;
Front: 231 mm dia. disc brakes; Rear: 200 mm dia.
drum brakes
Parking brake: lever type, console
Steering gear box Hydraulic power assisted Rack & Pinion steering gearwith collapsible steering column
Clutch Single Plate dry friction diaphragm type with 190
mm disc dia. With 285 cm2
friction area
Alternator 12 V, MF 50 Z
Fuel tank 42 L
Engine sump Servo Indica P 20 W/40; capacity: 4 L
Gear box Servo Gear HP80W
Steering gear box Servo Trans Fluid A
Brake fluid IS 8654/DOT3
Coolant Golden Cruiser 1400 M, Capacity: 6 L
Gross weight 1490 kg
Hindustan Motors Ambassador
Name of the supplier with address M/S Goenka Automobiles, G.S.Road, Guwahati -
781005
Name of vehicle manufacturer Hindustan Motors Ltd.
Name of Authorized dealer M/S Goenka Automobiles, G.S.Road, Guwahati -
781005
Vehicle Registration Number AR-01-A-4887
Model no.: 1800 ISZ, Colour: White; Body: SaloonDate of delivery 7/4/2001
Price Rs. 4,20,405.00
Year of manufacture 2001
Engine Fuel: Petrol; Cylinder: 4; Capacity: 1817 CC; Power:
75 Ps, 22.8 HP
Gear box All synchromesh 5 speed gear box including
overdrive
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Spring and suspension Front: Independent Suspension with torsion bear
springs and anti-roll bar
Rear: Semi-elliptical leaf springs
Shock absorber Front & Rear : Telescopic double acting shock
absorber
Number of wheels 4+1
Brakes Servo assisted dual circuit hydraulic with 21 mm
diameter drum brakes on front wheels, dual braking
on front and leading trailing on rear
Steering gear box Helical rack and pinion
Carburettor Electronic type fuel pump
Self starter 12 V, 45 A
Battery 12 V, Negative earth, 55 amp-hr at 20 hr rating
Alternator 12 V, 45 A
Fuel tank 42 L
Engine sump 4.5 LGear box 1.6 L
Rear axle 1.14 L
Steering gear box 0.20 L
Clutch disc diameter 215 mm
Gross weight 1554 kg
Tata Bus LP 1210 (45 seats)
Name of the supplier with address M/S Tata Engineering & Locomotive Co. Ltd.
Regional Sales Office, G.S Road, Guwahati - 781007
Name of vehicle manufacturer Tata Engineering & Locomotive Co. Ltd
Name of Authorized dealer M/S Himat Singha Auto Enterprise, Banderdewa,
Arunachal Pradesh
Vehicle Registration Number AR-01-3980
Model: Tata Bus LP 1210 (42 seats)
Date of delivery 28-02-1995
Price Rs. 7,12,552.08
Engine Cylinder: 6; Fuel: Diesel; Capacity: 4788 CC; Power:
31.5 HP
Gear box GBS-40 Synchromesh on 5 powered gears and sliding
mesh on reverse gearFront axle Forged Eye beam of Reverse Elliot type
Rear axle Hypoid type fully floating
Shock absorber Hydraulic Telescopic type at front and rear
Number of wheels 2+4+1
Size: 700 x 20 x 148 mm
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Brakes Hydraulic Brakes on front and rear wheels, assisted
by Single Chamber air pressure booster.
Steering gear box Heavy Duty re-circulating ball type with Universal
Joint
Wind Screen motor 14 W
Fuel injection Pump Inline type - MICO
Battery 12 V, 180 amp hr (20 hr rating)
Alternator 12 V, 35 Amps
Fuel tank 200 L
Engine sump 14 L
Engine oil filter 2.5 L
Oil bath air cleaner 0.5 L
Gear box 5.2 L
Transfer case 4.0 L
Front axle 4.35 LRear axle 5.0 L
Steering gear box 0.95 L
Brake fluid 1.7 L
Radiator 6.5 L
Gross weight 13,200 kg
Tata Bus LP 1210 (62 seats)
Name of the supplier with address M/S Himat Singha Auto Enterprise, Banderdewa,
Arunachal Pradesh
Name of vehicle manufacturer Tata Engineering & Locomotives Co. Ltd.
Name of Authorized dealer M/S Himat Singha Auto Enterprise, Banderdewa,
Arunachal Pradesh
Vehicle Registration Number ARC-1463 (62 seater Tata Bus)
Model No.: Tata LP 1210E/55
Date of delivery 11/6/1987
Price Rs. 3,78,977.20
Year of manufacture 1986
Engine Cylinder: 6; Fuel: Diesel; Capacity: 4788 CC; Power:
31.5 HP
Gear box GBS-40 Synchromesh on 5 powered gears and slidingmesh on reverse gear
Front axle Forged Eye beam of Reverse Elliot type
Rear axle Hypoid type fully floating
Shock absorber Hydraulic Telescopic type at front and rear
Number of wheels 2+4+1
Size: 700 x 20 x 148 mm
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Brakes Hydraulic Brakes on front and rear wheels, assisted
by Single Chamber air pressure booster.
Steering gear box Heavy Duty re-circulating ball type with Universal
Joint
Wind Screen motor 14 W
Fuel injection Pump Inline type - MICO
Battery 12 V, 180 amp hr (20 hr rating)
Alternator 12 V, 34 Amps with built in regulator
Fuel tank 160.0 L
Engine sump 14 L
Engine oil filter 2.5 L
Oil bath air cleaner 1.5 L
Gear box 5.2 L
Transfer case 4.0 L
Rear axle 5.0 L
Steering gear box 0.95 LBrake fluid 1.7 L
Radiator 6.5 L
Gross weight 12,180 kg
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APPENDIX C
WINSTAT AND MICROSOFT EXCEL 2003/2007
The WinSTAT is a registered trademark of Robert K. Fitch. It may be ordered online at
http://www.winstat.com/order/order.htm
A full functional demo version is available which is time-limited to 30 days after the
first installation. WinSTAT version 2009.1 has been used with Microsoft Excel 2007.
The WinSTAT toolbar looks like as shown below:
Graphics menu
The WinSTAT toolbar provides 4 menus viz. Statistics, Graphics, Data and Help, to
work with normal distribution, descriptive statistics, correlation functions, survival
analysis and a few more statistical tools besides serving the purpose of creation of
various types of charts.
The Graphics menu gives access to
WinSTATs graphics capabilities. The
following charts may be plotted with
WinSTAT:
1. Histogram
2. Means plot
3. Box & Whisker
4. Scatterplot
5. Cumulative frequency
6. Quality control
7. Pareto Chart
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Creating Pareto Chart
The information on Checksheet must be organized on worksheet as follows:
Others Engine Rear axle Transmission
45 42 21 4
It is not required to arrange the variables according to the descending order of their
frequencies as stipulated for analysis with Pareto Charts. Also, the frequencies may be
spread over any number of lines. In any case, the program will sum each column in its
entirety to calculate the Pareto chart.
From the dialog box, which allows selection of variables to be included in the chart, the
specified variables are produced in the output along with the cumulative frequency over
all the variables.
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APPENDIX D
GLOSSARY
Centre bearing: Used in open-type propeller shafts with tubular cross-section in the
third universal joint to support the centre of the drive line.
Concurrent engineering: It is a team approach to design, with specialists in
manufacturing, quality engineering and other disciplines working together with the
product designer at the earliest stages of the product design process. The other
approach is known as the Over-the-wall approach in which the specification limits are
usually determined by the design engineer without much interaction with or
knowledge of the manufacturing processes that must be used.
Differential pinion: A bevel pinion attached to the right end of the propeller shaft or
universal joint yoke, it rotates the crown wheel at right angles.
Engine: It generates power for locomotion. It converts chemical energy of the fuel to
mechanical energy. Engine develops power and torque.
Macro level analysis: Analysis not involving use of inspection instruments.
Radiator:A heat exchanges with hot coolant (water) from the engine entering the top
tank and passing through the core to the bottom tank. Cool atmospheric air is drawn
over the core by the cooling fan, leading to cooling of the radiator water.
Silencer: Also known as Muffler or Expansion Chamber, silencer is separate chamber
fitted on the exhaust system to reduce the pressure of the exhaust gases progressively
and lets out the exhaust gases to atmosphere at atmospheric pressure.
Strut: Part of Mac Pherson strut type suspension, mounted between the frame and the
stub axle where the wheel is mounted. The strut contains shock absorber and the
spring.
Timing belt: Part of the timing system by which the camshaft & fuel injection pump
are operated.
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Total Quality Management (TQM): It involves consideration of processes in all the
major areas: marketing, design, procurement, operations, distribution, etc. Approach
such as the TQM will ensure the implementation of the management commitment
represented in the quality policy, and provide the environment and information base
on which teamwork thrives, the culture changes and communications improve.
Universal joint spider: Connects the driver and the driven yokes of universal joint by
means of needle bearings.
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References
1. Montgomery, Douglas C., 2001, 4th
Edition, Introduction to Statistical Quality
Control, John Wiley & Sons, Inc. publication.
2. Juran, J.M., Gryna, F.M., Chua, R.C.H., Defeo, J.A., 2007, 5th
Edition, Jurans
Quality Planning and Analysis for Enterprise Quality, Tata McGraw-Hill
Publishing Company Limited.
3. Oakland, John S., 2003, 5th
edition, Statistical Process Control, Butterworth
Heinemann publication.
4. Leavengood, S., and Reeb, J., 2002, Statistical Process Control Pareto
Analysis and Check Sheets, Oregon State University.
5. Wisner, Priscilla, Statistical Process Control For Quality Improvement,
Qfinance, www.qfinance.com.
6. Rohani, J.M. & Teng, C.K., 2001, Improving Quality With Basic Statistical
Process Control Tools: A case study, Universiti Teknologi Malaysia.
7. Allen, Theodore T., 2006, Introduction to Engineering Statistics and Six Sigma,
Springer-Verlag London Limited.
8. Automotive Technology (Basics), Mahindra Institute of Learning Excellence
9. Websites:
www.carwale.com
www.spiritus-temporis.com
www.en.wikipedia.org
www.ranamotors.in
www.carsalesindia.com
clubs.hemmings.com
www.spiritus-temporis.com
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