Journal of Engineering Productivity Improvement by using Six-Sigma

International Journal of Engineering and Technology Volume 3 No. 12, December, 2013

ISSN: 2049-3444 © 2013 – IJET Publications UK. All rights reserved. 1056

Productivity Improvement by using Six-Sigma

Md. Enamul Kabir, S. M. Mahbubul Islam Boby, Mostafa LutfiDepartment of Industrial Engineering and Management,

Khulna University of Engineering & Technology, Khulna- 9203, Bangladesh

ABSTRACT

Globalization, advanced technology, and increased sophisticated customer demands change the way of conducting business. Old

business models no longer work in new economy. Defects rate of product plays an important role for the improvement of yield and

financial conditions of any company. The objectives of this paper are to study and evaluate processes of the case organization, to find

out current sigma level and finally to improve existing sigma level through productivity improvement. According to the objectives,

current sigma level has been calculated and given suggestions for improvement. This has been done by using six-sigma DMAIC

cycle. Especially in improve phase of DMAIC cycle, different improvement tools are used like 5s, supermarket and line balancing

etc. By using these it has been possible to improve productivity by reducing defect rate. This research work has been carried out in a

fan manufacturing company to show how to improve its productivity and quality by using Six-sigma. This paper related to work is

not only applied to fan manufacturing company but also in any other types of organizations. By implementing Six-sigma a perfect

synchronization among cost, quality, production time and control time will be observed.

Keywords: improvement, sigma level, DMAIC cycle, 5S, supermarket, line balancing.

1. INTRODUCTION

Six- Sigma is a statistical measurement of only 3.4 defects

per million. Six-Sigma is a management philosophy focused

on eliminating mistakes, waste and rework. It establishes a

measurable status to achieve and embodies a strategic

problem-solving method to increase customer. Satisfaction

and dramatically reduce cost and increase profits. Six-Sigma

gives discipline, structure, and a foundation for solid decision

making based on simple statistics. The real power of Six

Sigma is simple because it combines people power with

process power. The Six Sigma is a financial improvement

strategy for an organization and now a day it is being used in

many industries. Basically it is a quality improving process of

final product by reducing the defects; minimize the variation

and improve capability in the manufacturing process. The

objective of Six Sigma is to increase the profit margin,

improve financial condition through minimizing the defects

rate of product. It increases the customer satisfaction,

retention and produces the best class product from the best

process performance.

If an organization is focused on customer satisfaction, then

Six Sigma will offer a method and some tools for the

identification and improvement of both internal and external

process problems to better meet customer needs by

identifying the variations in organization’s processes that

might influence the customer’s point of view, negatively.

The purposes of this paper are

To study and evaluate processes at a fan

manufacturing company

To calculate the current sigma level of that

manufacturing company

To develop in order to get competitive advantage in

the long run

To give suggestions for improvements by using

Six-Sigma DMAIC process improvement methods.

2. LITERATURE REVIEW

The literature review will give a basic idea about the

evolution of six-sigma, what it is about and its methodology.

Some case studies to highlight its importance are also

discussed in this literature review. Case studies will brief

about six-sigma and how it has helped in productivity

improvement.

2.1 Six-Sigma Evolution

Though Fredrick Taylor, Walter Shewhart and Henry Ford

played a great role in the evolution of six-sigma in the early

twentieth century, it is Bill Smith, Vice President of Motorola

Corporation, who is considered as the Father of Six-sigma.

Fredrick Taylor came up with the methodology of breaking

systems into subsystems in order to increase the efficiency of

manufacturing process. Henry Ford followed his four

principles, namely continuous flow, interchangeable parts,

division of labor and reduction of wasted effort, in order to

end up in an affordable priced automobile. The development

of control charts by Walter Shewhart laid the base for

statistical methods to measure the variability and quality of

various processes.

Later during the 1950s, the Japanese Manufacturing sector

revolutionized their quality and competitiveness in the world

based on the works of Dr. W. Edwards Deming, Dr. Armand

Feigenbaum, and Dr. Joseph M Juran. Dr. W. Edwards

Deming developed the improvement cycle of ‘Plan-Do-

Check-Act’, better known as the PDCA cycle. Dr. Joseph M

Juran gave to the world his ‘Quality Trilogy’ and it was Dr.

Armand Feigenbaum who initiated the concepts of ‘Total

International Journal of Engineering and Technology (IJET) – Volume 3 No. 12, December, 2013


Quality Control’ (TQC). Between 1960 and 1980, the

Japanese understood that everyone in an organization is

important to maintain quality and so training programs were

conducted for almost all employees not considering the

department they belong to. Any organization that is

dynamically working to build the theme of six-sigma and to

put into practice, the concepts of six-sigma, in its daily

management activities, with noteworthy improvements in the

process performance and customer satisfaction is considered

as a six –sigma organization [3].

2.2 Related Works

M. Soković et al. undertook projects to identify areas in the

process where extra expenses exist, identify the biggest

impact on production expenses, introduce appropriate

measurement system, improve process and reduce expenses

on production times, and implement improvements [4].

Gustav Nyren represented the variables influencing the

chosen characteristics variable and then optimized the process

in a robust and repeatable way [5].John Racine focuses on

what six-sigma is today and what its roots are both in Japan

and in the west and what six-sigma offers the world today [6].

Zenon Chaczko et al. introduced a process for the module

level integration of computer based systems which is based

on the Six-sigma Process Improvement Model, where the

goal of the process is to improve the overall quality of the

system under development [7]. Philip Stephen highlighted a

distinct methodology for integrating lean manufacturing and

six-sigma philosophies in manufacturing facilities [8].

Thomas Pyzdek focuses that helps the user identify worthy

projects and move them steadily to successful completion, the

user identify poorly conceived projects before devoting any

time or resources to them, the user identify stalled projects

and provide them with the attention they need to move

forward again, the user decide when it’s time to pull the plug

on dead projects before they consume too much time and

resources and provide a record for the user that helps improve

the project selection, management and results tracking

process.

2.3 Six Sigma Improvement Approach

The main thing of Six Sigma is to taking the existing product,

process and improves them in a better way. It is a very

powerful approach to achieve the financial goals for the

organization and improving the company’s value by the

following;

Data driven

Project based

Disciplined and systematic

Customers focused (internal & external)

Success of every organization is dependent on, how to

introduce and implement Six Sigma in the organization. For

clear understanding, “Six Sigma Onion” is a best example for

showing the process of implement Six Sigma in the

organization

2.4 Process Capability

Sigma value increases the process performance in a better

way. Another way of measure the process capability and

performance by the statistical measurements like Cp, Cpk, Pp

and Ppk. The Six Sigma means a 3.4 % defects part per

million or yield of 99.9997% (perfect parts). Following is the

table of comparison of different Sigma values at different

defects part per million and capability of process here [9].

Table 2.1 Six Sigma Value Chart

SIGMA DPMO COPQ CAPABILITY

6 sigma 3.4 <10% of sales World class

5 sigma 230 10 to 15% of sales

4 sigma 6200 15to 20% of sales Industry Average

3 sigma 67000 20 to 30% of sales

2 sigma 310000 30 to 40% of sales Non Competitive

1 sigma

DPMO- Defects per Million Opportunities

COPQ- Cost of poor Quality

2.5 DMAIC

The DMAIC methodology uses a process-step structure.

Steps generally are sequential; however, some activities from

various steps may occur concurrently or may be iterative.

Deliverables for a given step must be completed prior to

formal gate review approval. Step Reviews do occur

sequentially. The DMAIC five steps are

Step1. DEFINE the problem and scope the work effort of the

project team.

Step2. MEASURE the current process or performance.

Figure 2.1 DMAIC Methodology



Step3. ANALYZE the current performance to isolate the

problem

Step4. IMPROVE the problem by selecting a solution.

Step5. CONTROL the improved process or product

performance to ensure the target(s) are met.

A DMAIC project typically runs for a relatively short

duration (three to nine months), versus product development

projects (using UAPL or DFSS) and operational line

management (using LMAD), which can run years. Given the

relatively shorter duration to other types of Six Sigma

methodologies, we distinguish the DMAIC as having five

steps, rather than phases.

2.6 Analysis Tool

2.6.1 Process Block Diagram

In order to visualize the changes required to convert raw

materials into a finished product, it is necessary to specify the

basic transformations that define the production process. The

same is true in representing the major steps involved in

offering a service [10]. Each of the basic transformations

corresponds to a stage in the process and can be accomplished

in a variety of ways depending on technologies available and

the economic and other restrictions to the problem. A block

diagram displays the structure of the process in the broadest

possible terms. The number of stages depends on the

complexity of the product and the extent of vertical or

horizontal integration in the organization. A typical process

block diagram for one way communication process is shown

below:

2.6.2 Production Layout

In developing a layout for an operation system the optimum

allocation of space is seek to the components of production

process. The best arrangement of facilities are tried to

determine and equipment capable of satisfying anticipated

demand at lowest cost. In layout all elements of a process

must be integrated. Special care must be taken to create an

environment conducive to high productivity and the

satisfaction of social and psychological needs of the people at

work. The layout of a production floor plays an important

role in the formulation of groups of people and

communication links with peers, superiors and subordinates.

For existing system the proposed layout must satisfy

constraints from existing buildings, docks and other physical

structure that form part of the production process. Sometimes

difficulties encountered in the production layout phase make

it necessary to revise previous decisions on product and

process design so that in an iterative fashion management can

arrive at an “optimum” combination of decisions for all facts

of the system- design problem [10].

2.6.3 Cause and Effect Diagram

Cause & effect diagram is a common tool in improvement

projects. It is also known as Ishikawa diagram after its

originator or as a fishbone diagram. This tool is used to come

up with new ideas like in a brainstorming session but in a

more balanced way. It is often used as input to a Design of

Experiments. A type of cause &effect diagram has an input of

x variables, both noise and control variables and an output of

variables.

Figure 2.2 A Typical Cause & Effect Diagram

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2.7 Improvement Tool

2.7.1 5s

5s is a program developed by the Japanese. It is a series of

activities designed to organize the work environment so that

everything is visual and problems aren’t covered up. While

5S system improves the quality and safety, it provides

effective company organization and focuses on the

simplification of work environment and the minimization of

wastes principles. It is expressed by five Japanese words that

express cleaning and order at the company and accepting this

as work discipline. These words are:

Seiri: Sort

Seiton: Set in Order/Straighten

Seiso: Shine/Sweep

Seiketsu: Standardize

Shitsuke: Sustain/Self-discipline

The greatest feature of 5S approach is that it is simple; for

that reason it easily finds area of application. Forming a

ground for the other improvement activities, 5S is an

important term that carries priority in improvement at a

company. The liability and failure, if available, in this kind of

a change belongs to the administration, not to the personnel.

If the personnel recognize the importance of the innovation

and developments to be realized, then the established system

will be operated in a healthier manner. [11]

2.7.2 Supermarket

Supermarkets are particularly effective at addressing the

Muda caused by transport and unnecessary movement. As

supermarket come closer to the line-side and reduce the Muda

caused by unnecessary movement and transport.

Supermarkets also reduce the Muda caused by waiting.

Supermarkets are never fixed. The supermarket typically

comprises meat, fresh produce, dairy, and baked goods

departments, along with shelf space reserved for canned and

packaged goods as well as for various non-food items such as

household cleaners, pharmacy products and pet supplies.

Supermarkets usually allocate large budgets to advertising,

typically through newspapers. They also present elaborate in-

store displays of products.

2.7.3 Kaizen

Kaizen was created in Japan following World War II. The

word Kaizen means "continuous improvement". It comes

from the Japanese words 改 ("kai") which means "change" or

"to correct" and 善 ("zen") which means "good".

Kaizen is a system that involves every employee - from upper

management to the cleaning crew. Everyone is encouraged to

come up with small improvement suggestions on a regular

basis. This is not a once a month or once a year activity. It is

continuous. Japanese companies, such as Toyota and Canon,

a total of 60 to 70 suggestions per employee per year are

written down, shared and implemented.

Kaizen involves setting standards and then continually

improving those standards. To support the higher standards

Kaizen also involves providing the training, materials and

supervision that is needed for employees to achieve the

higher standards and maintain their ability to meet those

standards on an on-going basis. [12]

2.7.4 Line Balancing

Line balancing is the assignment of work to station in a line

so as to achieve the desired output rate with the smallest

number of workstations. Normally, one worker is assigned to

a station. The line that produces at the desired pace with the

fewest worker is the most efficient one. Achieving this goal is

much like the theory of constraints, because both approaches

are concerned about bottleneck. Line balancing differs in how

it addresses bottlenecks. Rather than, (1) taking on new

customer orders to best use bottleneck capacity or (2)

scheduling so that bottleneck resources are conserved, line

balancing takes a third approach. It creates workstation with

workloads as evenly balanced as possible. It seeks to create

workstations so that the capacity utilization for the bottleneck

is not for the higher than for the other workstations in the

line. Another difference is that line balancing applies only to

line processes that do assembly work or to work that can be

bundled in many ways to create the jobs for each workstation

in the line.

The analyst begins by separating the work into work

elements, which are the smallest units of work that can be

performed independently. The analyst then obtains the time

standard for each element and identifies the work elements,

called immediate predecessors that must be done before the

next elements can begin [13].

3. FINDINGS OF THE STUDY

To implement six-sigma it is needed to follow DMAIC

approach step-by step. In the following sections, this

approach is briefly described for the concerned organization.

3.1 Process Definition

In this stage, the process which is needed to improve is

identified by proper investigation. To understand the whole

manufacturing process of lovely fan, a process block diagram

is shown in Figure 5 schematically including the different

stages of production. Block diagram has become a key tool in

the development of information systems, quality management

systems, and employee handbooks. Here in this stage the

processes are clearly identified and the critical process for

improvement is recognized. Though it has not been done,

benchmarking is also essential here to understand the

situation.

3.2 Process Measurement

In this measurement stage, different variables are identified to

measure. As it has been tried to improve the sigma level of

the organization, initially the present sigma level has been

measured by using an Excel based sigma calculator and it was

found that the present sigma level of the studied organization

not satisfactory and it was 3.7 only. Hence, to improve this

level, different quality improvement tools have to be

employed and the organization has to be set a milestone to

achieve.

http://en.wikipedia.org/wiki/Meat

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http://en.wikipedia.org/wiki/Canning

http://en.wikipedia.org/wiki/Pharmacy

http://en.wikipedia.org/wiki/Pet



3.3 Process Analysis

It is a very important stage to consider because lack of proper

analysis may lead to the process to a wrong way which will

deviate from the main function of improvement. In this stage,

different basic tools of quality are preferably used to analyze

the real condition of the processes. Every successful work

goes on some specific sequence. This work also completes

some specific step. After completing each successful, it is

necessary to move next step. The steps that are followed for

data analysis are:

Step 1- Find out the existing sigma level of the production

shop.

Step 2- Analysis the existing layout of the production shop.

Step 3- Analysis the existing operation sequence by the

process block diagram.

Step 4- Analysis the existing problem by cause and effect

diagram.

3.3.1 Find out The Existing Sigma Level of The

Production Shop

Sigma level is a procedure to know the existing condition of a

production shop. The calculation of sigma level is based on

the number of defects per million opportunities (DPMO). In

order to calculate DPMO, three distinct pieces of information

are required:

a) The number of units produced.

b) The number of defects opportunities per unit.

c) The number of defects.

The actual formula is:

DPMO=

(1)

For this purpose the relevant data is collected. By using this

data the defect rate of each process is calculated and

converted it into the total defect. From collected data, the

number of units produced was 240 pieces per day, the number

of defects opportunities per unit was 5 and the number of

defects was average 18 pieces per day. Finally this

information is put into sigma level calculator. This

automatically finds the DPMO of the production shop which

is 15000. The sigma level calculator used to find the sigma

level is shown following:

After plotting the required information into sigma level

calculator, the calculator shows that the sigma level of the

production shop is 3.7.

3.3.2 Analysis The Existing Layout of The Production

Shop

The layout problem presents a challenge to management

because of the complex interactions of several key factors and

the difficulty in assessing their impact on the system

performance. The production layout is used this research for

the following purpose:

Placing equipment in a position resulting in its

maximum utilization (adjusting machine capability

and manpower utilization).

Reducing congestion in the flow of materials or

people through successive stages in the process (by

applying supermarket).

Providing easy access for equipment maintenance

and repair.

Creating efficient production lines for a smooth and

rapid product flow

Suitable means for fast and safe materials handling.

Maintaining best utilization of space.

Maintaining best utilization of human resources by

providing a comfortable and safe working

environment.

The production layout of the case organization is given in

Figure4.1.



Figure 3.1: Production Layout of Case Organization

3.3.3 Analysis the Existing Operation Sequence by Process

Block Diagram

After completing the successful analysis of production layout

further study is going on process block diagram. To find out

the existing problem of a complete production process, it is

more preferable to represent the operation sequence by

process flow diagram. For this purpose, the operation

sequence is analyzed and obtained a chart shown in Figure

3.2



Figure 3.2: Process Block Diagram of Case Organization

3.3.4 Analysis the Existing Problem by Cause & Effect

Diagram

To analyze a problem cause & effect diagram is one of the

best tools. After obtaining process flow diagram, the next step

is to find the root cause and sub-cause of the existing process.

The required cause & effect diagram is shown in Figure 3.3



Figure 3.3: Cause & Effect Diagram of Case Organization

3.4 Process Improvement

In this stage, improvement strategies are developed for

achieving the desired goal. According to the analysis, perfect

measures should be taken to progress the current situation. As

the major concern to implement six-sigma here in the case

organization to improve the productivity, it is highly needed

to diagnose the critical issues. For this reason 5s, supermarket

and line balancing are used to improve the current situation of

the production shop which is discussed below respectively.

3.4.1 5s

When the problem and sub- problem is known then it is very

easy to improve the existing process. One of the major

problems of the production system is disorder the materials,

tools, affluent, work-in-progress etc. It is often happened that

a worker do not find a tool or material in first time. For this

reason it spends time. Disorderly work-in-progress causes

increasing difficulty to pick up. Before applying 5s in any

organization, it is necessary to know the 5s score of the

defective product per day. The 5s score of the case

organization is given in Table 4.1.

Table 3.1: 5s score of 30 days for Case Organization

Sl No Date Defective Product 5s Score

01 11.12.2010 17 2.76

02 13.12.2010 20 2.95

03 14.12.2010 18 2.94

04 15.12.2010 17 2.94

05 16.12.2010 19 2.84

06 18.12.2010 16 2.88

07 19.12.2010 22 2.95

08 20.12.2010 13 2.92

09 21.12.2010 21 2.95

10 22.12.2010 18 2.94

11 23.12.2010 16 2.81



12 24.12.2010 18 2.89

13 26.12.2010 21 2.95

14 27.12.2010 19 2.89

15 28.12.2010 20 2.95

16 29.12.2010 18 2.94

17 30.12.2010 17 2.88

18 01.01.2011 15 2.93

19 02.01.2011 18 2.94

20 03.01.2011 16 2.81

21 04.01.2011 18 2.89

22 05.01.2011 16 2.94

23 06.01.2011 15 2.87

24 08.01.2011 15 2.87

25 09.01.2011 20 2.95

26 10.01.2011 19 2.89

27 11.01.2011 18 2.89

28 12.01.2011 17 2.94

29 13.01.2011 17 2.94

30 15.01.2011 18 2.94

From Table 3.1, it is clearly seen that the 5s score is not so

very good in every day. Besides this average 5s score in 30

days is very poor which is 2.91.For this reason improvement

is necessary in this case. The 5s score is determined based on

some quality parameter. These are Rpm, Watt, Air

Circulation, Ampere, Bearing sound, Balancing, Body short,

Coil Cutter, Low Speed, Magnetic sound, Painting and

Bearing Housing. By applying 5s, it is possible to improve if

the organization maintains the following improvement

technique:

Sort

Importance of particular items should be ranked and

eliminated what was not needed such as chop pieces.

Shop has to clean including all cabinets and ceiling

pipes.

Old sinks and calibration stations should be

upgraded.

Entire shop would be painted with special industrial.

Set in order

Repositioned air tools, grinder and electrical

stations, making processes more efficient.

Proper labels for all materials should be developed.

Functional placement for storage and retrieval of

materials should be created.

Each employee should be assigned an individual

workstation.

Shine

Daily inspections of work areas and equipment have

to perform.

Trash and foreign matter should be eliminated from

the workstations and keep area clean on a continuous

basis.

Standardize

The area has to maintain with consistent operations.

Clear, simple and visual cues should be used to

detect abnormalities.

Sustain:

Weekly team meetings should be held to discuss

accomplishments and opportunities for

further improvements.



Applying 5s score totally depends on the step sustain. It is not

possible to improve after completing first four steps without

sustain. So the case organization will only improve if sustain

is properly maintained.

3.4.2 Supermarket

To solve work-in-progress disordering, supermarket is used

as an improving tool.

Figure 3.4: Applying Supermarket of Case Organization



By applying supermarket, the following benefits are obtained:

a) Supermarket reduces the hazards of the production shop.

b) It helps to find out materials easily.

c) It helps to find out tools for the first time.

d) It reduces the floor space and best utilization of floor

space.

The running way of case organization is too much complex

with the criteria of time and distance. So the main purpose of

this undergraduate research paper is to deal with these

obstacles and reducing time & distance as well as increasing

the production rate, ultimately defects rate will fall down.

There are almost 18 defects which are occurring everyday due

to some lacking of existing layout. The main reasons are

improper sorting, heavy working pressure of each worker,

disorderly move of some workers, performing critical task

with small space and bottleneck processes. So if anyhow it is

possible to reduce the causes, it is possible to reduce amount

of damage product and simply it can be done successfully by

applying 5s & supermarket. 5s and supermarket have

smoothly solved the above causes which are discussed in the

section of 4.4.1 and 4.4.2.

3.4.3 Line Balancing

The industries must produce momentous quantities in shorter

lead times. Product is highly correlated with high level of

productivity; production floor should be balanced in shorter

possible time and effective way for each style and quantity.

The focal constraint against the higher productivity is the

difference in individual capacity which is the mode of

improper line balancing and bottle neck process. This paper is

based on an effective layout model where to hit upon the

bottleneck process through benchmark capacity. The research

shows that this balanced layout model has increased the

efficiency by 19% and labor productivity by 73%.

3.4.3.1 Procedure of Line Balancing

The paper is discussed comparing the productivity and

efficiency before and after applying the balancing technique.

Considering experience, capacity, production line is selected.

Two important attributes have been considered, one is

possible standard method for each process and another is

considerable time in between the input has been fed to actual

individual capacity of each worker. The time is recorded to

make each process for each and every worker to find out the

number of operator and individual capacity. To find out the

(standard allowable minute) S.A.M value, process wise

capacity has been calculated, in addition to that the target,

benchmark capacity, actual capacity, labor productivity and

line efficiency are calculated. Line has been balanced

considering the bottleneck and balancing process where the

balancing process has shared the excess time after the

benchmark production in the bottleneck process. After

balancing, new manpower has been proposed and final

capacity of each worker has been reallocated. We have

compared the line graph after balancing the line, labor

productivity and line efficiency. Finally a proposed

production layout has been modeled with balanced capacity.

3.4.3.2 Equations

The following equations are used for line balancing:

Target = *

100% (2)

Labor Productivity =

(3)

Machine Productivity =

(4)

Line Efficiency=

* 100% (5)

3.4.3.3 Calculations

Table 3.2 Labor and Machine Productivity and Line

Efficiency Before Balancing the Line.

Total output per day 240 Pieces

Total manpower 98

Working time 480 minutes

SAM 126.05 minutes

Labor productivity 2.45

Machine

productivity

8.28

Line efficiency % 64.31

Process wise capacity of each work station has been found

where Standard allowable minutes (S.A.M) has been

calculated. The above table show the target per hour for the

line calculating total 98 manpower worked on that line for

480 minutes with a S.A.M value of 126.05. The Bench mark

target have standardized of 298 pieces of production at 80%

efficiency. Observation before balancing the line has been

reflected as labor and machine productivity is 2.45 and 8.28,

line efficiency is 64.31%.

3.4.3.4 Bottleneck process

Some variations are identified in process capacity from the

bench mark target and the lower capacity from the bench

mark target is the bottleneck process as production flow

would stick on the bottleneck point. Comparing total capacity

of each process to the 80% bench mark target, the bottleneck

processes have identified named Pressing 1, Pressing 2,

Binding and Grinding, marked red color.



3.4.3.5 Balancing process

Balancing method is very essential to make the production

flow. Considering working distance, type of machines and

efficiency, workers who have extra time to work after

completing their works, have been shared their work to

complete the bottleneck processes.

Table 3.3 Balancing Process

Shifted

manpower

From To

Process No Time Process

No

Time

1 9 36 4 24

1 10 42 5 18

1 12 20 7 40

1 22 50 16 10

Operator who work in Process no. 9 Hydraulic pressing, have

been worked for 36 minutes per hour in her first process,

capacity 42 pieces and then have been worked in the process

no. 4 pressing 1 for last 24 minutes to make additional 12

pieces for overall capacity of 42 pieces on process no. 4.

Similarly Process no. 10 shaft pushing have been worked for

42 minutes and rest 18 minutes have been worked on process

no. 5 pressing 2 to make total capacity of 39 pieces which

was originally 30 pieces. Process no.12 and 22 have been

similarly worked on the process no.7 and 16 for the capacity

of 43and 41 pieces per hour.

3.5 Process Control

After taking appropriate actions for improving the process, it

has been checked again. On the basis of the results of this

assessment, previous steps may be repeated to achieve the

desired level. It is not possible always to get success at the

first time, so recurring of all the steps will lead the process to

be set at the preferred point.

Figure 3.5: Proposed Layout for the Case Organization



4. RESULTS & DISCUSSIONS

The used improvement tools have helped to improve in this

production line. Basically 5s and supermarket is the visually

applicable tool so it is not possible to show improvement

graphically by using these two tools. But if any organization

can follow these tool that have discussed above then the

organization must be improved.

Changing from traditional layout to balanced layout model,

there are considerable improvements have moved which are

given below:

Table 4.1 Bench Mark Target, Labor and Machine Productivity and Line Efficiency After Line Balancing

Total output per day 312 Pieces

Total manpower 98

Working time 480 minutes

SAM 126.05 minutes

Target/Hour 373 100% efficiency

Target/Hour 298 80% efficiency Bench Mark



Labor productivity 3.18

Machine productivity 10.75

Line efficiency % 83.60

In a day we have boost up the production up to 312 and with

manpower of 98, line efficiency has been improved from

64.31% to 83.60% which is shown in above table. The Bench

mark target have standardized of 298 pieces of production at

80% efficiency.

There were some uncertainties in the validity and reliability

of the sampled data. These were based on the assumption .As

the main purpose of this research is to increase productivity,

it has been tried to achieve this by improving the level of

sigma. Though this case study has been conducted in a fan

manufacturing organization, the procedures and the outcomes

will be suitable for any manufacturing organization. During

the study not all the information was collected instantly, but

some previous records have been also used for better

understanding.

The DMAIC problem solving approach has helped to reach

measurable results and conclusions. An incitement to develop

feasible solutions is created by this methodology. The

magnitude of this research paper has restricted the possibility

to implement all suggested improvements. It is seemed that a

project of smaller magnitude would have been more suitable

in order to complete the control phase in full. This method is

endorsed since it is easy to apply and provides a structured

approach to problem solving.

During this research paper, key information and experience

was accessible, giving a better overall view and a more

effective progress. By doing this, it is possible to access a

much greater base of knowledge and improve morale. This is

done when “everyone”, from operating personnel to

management, feels that they are part of the solution.

All the charts and diagrams used here are drawn carefully to

show the real scenario of the case organization. The

organization is trying itself to improve its productivity, but

without using appropriate tools and techniques, it is almost

impossible to make that happen.

5. CONCLUSION AND

RECOMMENDATIONS

5.1 Conclusion

The six-sigma framework provides an impetus for

establishing best practice with the company. It also provides

the company with a performance benchmark on which it

could base its future performance enhancement programs. As

it has been observed that the level of its sigma is not

satisfactory, there is no way to improve this by DMAIC. The

implementation of six-sigma will save money which will

result higher profit of the organization. As the businesses are

influenced by globalization, the competition is arising more

and more and so, to sustain in the global business every

organization needs to maintain appropriate quality level. This

study will contribute to a new management approach on

improving business process for both efficiency and consistent

quality customer service. After reviewing the benefits and

limitations behind Six Sigma, a company should determine



whether or not Six Sigma is for them. A clear trend is that Six

Sigma is diversifying into large service oriented

organizations. In the case organization it is noted that the

workers are very busy to produce their expected amount of

fan. Almost all time they perform repetitive task which waste

time. As a result, sometimes they produce defective fan. By

applying 5s and supermarket, it is possible to reduce

repetitive task by saving time which have shown on data

analysis. Consequently, there is less possibility for producing

defective fan which is the main target of six-sigma. On the

other hand by applying line balancing, productivity increases

from 240 to 312 per day by reducing defect. Finally it is said

that, it is possible to improve productivity by using six-sigma

which is the main purpose of this study. In the future, it is

likely that more changes will emerge; making Six Sigma an

even more beneficial application for organizations of all types

and sizes. It is believed that other companies can learn the

insights from this study to identify further research areas for

efficiency and quality services. To ensure this quality and

also the sustainability, six-sigma will no doubt play a vital

role in the long run.

5.2 Recommendations for Future Research

There are several approaches to choose from when the goal is

to increase the productivity of a fan manufacturing company.

The techniques used in this research paper have been limited

due to insufficient time and resources. In this research paper

only 5s, supermarket and line balancing are used as

improvement. These have given a better solution. But if any

one uses other technique of industrial engineering then he

will get more benefit than this research paper . If it is decided

to use the data in future studies it would be interesting .By

this way it may be possible to specify high productivity. The

quest for higher productivity will never stop and the project

extreme fan manufacturing will proceed. An important

suggestion for future work is to test if the findings are

applicable to other products and machines within the factory.

A deeper understanding could possibly make the conclusions

from this study more understandable and easier to apply to

other products.

Result would have been more effective if we would have

taken some large quantity order and balancing the process is

highly related to the type of machines as machine utilized in

bottleneck and balancing process should be similar.

Further improvements in the productivity can be achieved by

considering large amount of order minimum 10000pieces.

The new bench mark target which can be the further chance

of improvements to balance the line with this new bench

mark target. Proposed layout model has been followed the

logic of modular system (one worker works more than two

processes who is skilled on all processes and these

combination of skilled workers finish their work in piece flow

production) and traditional system (one worker works in one

process and all the workers who may be skilled or not finish

their work in bundle flow production) both together where

only modular production system can be applicable with a

series of skilled workers to achieve more productivity. On

this occasion, skilled workers are eligible for the production

processes and proper training and supervision is essential to

achieve the optimum improvements on productivity and

efficiency.

REFERENCES

[1] Stevenson WJ,2005, ‘Competitiveness, Strategy and

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[2] Park, SH, 2003, ‘Six Sigma for Quality and

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[3] Siddhartan Ramamoorthy, 2003, ‘Lean Six Sigma

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[11] Korkut,D.S., Cakicier, N., Erdinler,E.S,2009, “5s

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Duzce,81620, Turkey, Istanbul University, Faculty of

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Numarine Yacht Company, Istanbul Turkey and

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[12] www.graphicproducts.com/tutorial/kaizen

[13] Krajewski, L.J, University of Notre Dame, Ritzman

L.P, The Ohio State University and Boston College,

Malhotra M.K, University of South Carolina,2007,

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8th

edition, Pearson Education ,Inc.

APPENDIX

The 5s Score Of 30 Days For Case Organization

5s score for the date of 11.12.2012

The 5s score of the day is 2.76























































































Documents

Journal of Engineering Productivity Improvement by using Six-Sigma