Statistical Analysis of Repair and Maintenance of Institute Vehicles Nerist Diplomaproject

7/31/2019 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


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


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


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


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


failures and system-assemblies for Tata

Indigo GLX

25

3.3


failures and system-assemblies for

Ambassador 1800 ISZ

26

3.4



LP1210 bus (42 seats)

26

3.5




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


31

3.10Sub system 'Front axle and brakes' bar

diagram for Tata LP1210 bus (42 seats)

32

3.11



Indigo GLX

32

3.12Sub class 'Support systems' bar diagram for

Tata Indigo GLX

33

3.13


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



Ambassador 1800 ISZ

34

3.15




34


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


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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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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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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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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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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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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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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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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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


defects or opportunities.

first by showing the pro

comprise. This is based

problem.


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


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


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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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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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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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:


31/63



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.


33/63



Fig (3.1): Pareto Chart of number of occurrences of failures and system-assemblies

for Maruti Versa SDX


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



34/63




for Hindustan Ambassador ISZ 1800


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


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



35/63




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


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


36/63



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


37/63



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


38/63



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



39/63



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


N

o.

offailures


40/63



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.


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


No.

offa

ilures


41/63



Fig. 3.12 Sub-class Support systems' bar diagram for Tata Indigo GLX

Hindustan Motors Ambassador 1800 ISZ


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


No.

offailures


42/63



Fig. 3.14 Sub-class Support systems' bar diagram for Hindustan Motors 1800 ISZ

Tata bus LP1210 (62 seats)


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



43/63



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


44/63



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


45/63



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


46/63

Stati


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


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


47/63

Stati


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.


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


48/63



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


49/63




Self starter assembly defects


50/63




brake assembly defects


51/63



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.


52/63



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)


53/63



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


Model: Indigo GLX, 475 SI MPFI; Colour: Meadow

Green; Body: Saloon



54/63



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


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


Model no.: 1800 ISZ, Colour: White; Body: SaloonDate of delivery 7/4/2001

Price Rs. 4,20,405.00


Engine Fuel: Petrol; Cylinder: 4; Capacity: 1817 CC; Power:

75 Ps, 22.8 HP

Gear box All synchromesh 5 speed gear box including

overdrive


55/63



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


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)


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


56/63



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


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


57/63



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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