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Page 1: A LEAN SIX -SIGMA MANUFACTURING PROCESS … · A Lean Six-Sigma Manufacturing Process Case Study  500 editor@iaeme.com and implement the lean and six-sigma in organization

http://www.iaeme.com/IJMET/index.

International Journal of Mechanical Engineering and Technology (IJMET)Volume 8, Issue 7, July 2017, pp. Available online at http://www.iaeme.com/IJMEISSN Print: 0976-6340 and ISSN Online: 0976 © IAEME Publication

A LEAN SIX

PROCESS CASE STUDY

Hari

Department of IndustrialInstitut Teknologi Sepuluh Nopember

ABSTRACT

Lean Six-Sigma – LSS

manufacturing floor. Initiated in the automotive industry, continuous improvement

were implemented to improve the manufacturing process change. LSS

elaborate a case where lean

process. Benefits of LSS are to

process inventory. Six-sigma focuses on process flow and pressure

variations. Value Stream Mapping

to reveal problems lean, such as

describes all activity of process,

Therefore, a new VSM is corrected to redesign a new lean process flow through

process improvement with elimination of the root causes of waste. This paper proves

the using of LSS principles and

Key words: Lean Six-Sigma(VSM), Waste, Manufacturing

Cite this Article: Hari Supriyanto and Diesta Iva MaftuhahManufacturing Process Case Studyand Technology, 8(7), 2017, pp. 498http://www.iaeme.com/IJME

1. INTRODUCTION

Six-sigma concept was introduced by Bill Smith in 1986, a senior engineer and scientist within Motorola’s communication division in response to problem associated with high warranty claims. Six-sigma is a now widely applied program for company quality improvement. The first of organization to use sixPolaroid, and Texas InstrumentGeneral Electric, in the mid. 1990s, and was followed by another organizations structure such as Sony, Dow Chemical, Bombardier and GlaxoSmithKline

The success of the efforts at Motorola was not just achieving sig sigma quality level rather the focus was on reducing defect rate in process through the effective utilization of powerful and practical statistical tools and techniques. This would lead to enhance quality of service, improve productivity and customer satisfaction, reduced cost of operations or cost of poor quality, and so on. The quality improvement developed by Motorola can be seen i

IJMET/index.asp 498 [email protected]

International Journal of Mechanical Engineering and Technology (IJMET) 2017, pp. 498–509, Article ID: IJMET_08_07_057

http://www.iaeme.com/IJMET/issues.asp?JType=IJMET&VType=8&IType=76340 and ISSN Online: 0976-6359

Scopus Indexed

A LEAN SIX-SIGMA MANUFACTURING

PROCESS CASE STUDY

Supriyanto and Diesta Iva Maftuhah

Industrial Engineering, Faculty of Industrial TechnologyInstitut Teknologi Sepuluh Nopember, Surabaya, Indonesia

SS is an approach that has been proven and applied in many

manufacturing floor. Initiated in the automotive industry, continuous improvement

ed to improve the manufacturing process change. LSS

elaborate a case where lean six-sigma principles can be adopted for the improvemen

process. Benefits of LSS are to reduce production lead time and to decrease work in

gma focuses on process flow and pressure

Value Stream Mapping-VSM is one of the lean tools used to recognize and

, such as the sources of waste and find the hidden waste

process, both value added and non-value added activity.

a new VSM is corrected to redesign a new lean process flow through

process improvement with elimination of the root causes of waste. This paper proves

principles and its application in case study for a product (gas stove)

Sigma (LSS), Continuous improvement, Value Stream Mapping anufacturing.

Hari Supriyanto and Diesta Iva Maftuhah. A Lean SixManufacturing Process Case Study. International Journal of Mechanical Engineering

, 8(7), 2017, pp. 498–509. aeme.com/IJMET/issues.asp?JType=IJMET&VType=8&IType=7

as introduced by Bill Smith in 1986, a senior engineer and scientist within Motorola’s communication division in response to problem associated with high

sigma is a now widely applied program for company quality of organization to use six-sigma was Raytheon, Allied Signal,

Polaroid, and Texas Instrument, but the amazing incident occurred after further developed by 1990s, and was followed by another organizations structure such

, Dow Chemical, Bombardier and GlaxoSmithKline-GSK [1-3].

The success of the efforts at Motorola was not just achieving sig sigma quality level rather the focus was on reducing defect rate in process through the effective utilization of powerful

ical statistical tools and techniques. This would lead to enhance quality of service, improve productivity and customer satisfaction, reduced cost of operations or cost of poor

The quality improvement developed by Motorola can be seen i

[email protected]

T&VType=8&IType=7

SIGMA MANUFACTURING

l Technology, Indonesia

is an approach that has been proven and applied in many

manufacturing floor. Initiated in the automotive industry, continuous improvement

ed to improve the manufacturing process change. LSS is used to

principles can be adopted for the improvement

decrease work in

gma focuses on process flow and pressures to minimum

VSM is one of the lean tools used to recognize and

the sources of waste and find the hidden waste. VSM

value added activity.

a new VSM is corrected to redesign a new lean process flow through

process improvement with elimination of the root causes of waste. This paper proves

a product (gas stove).

Value Stream Mapping

A Lean Six-Sigma International Journal of Mechanical Engineering

asp?JType=IJMET&VType=8&IType=7

as introduced by Bill Smith in 1986, a senior engineer and scientist within Motorola’s communication division in response to problem associated with high

sigma is a now widely applied program for company quality sigma was Raytheon, Allied Signal,

but the amazing incident occurred after further developed by 1990s, and was followed by another organizations structure such

The success of the efforts at Motorola was not just achieving sig sigma quality level rather the focus was on reducing defect rate in process through the effective utilization of powerful

ical statistical tools and techniques. This would lead to enhance quality of service, improve productivity and customer satisfaction, reduced cost of operations or cost of poor

The quality improvement developed by Motorola can be seen in the

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Hari Supriyanto and Diesta Iva Maftuhah

http://www.iaeme.com/IJMET/index.asp 499 [email protected]

following Table 1. Furthermore, six-sigma, as a quality improvement methodology, has gained considerable attention [4]. Application of the six-sigma methods allowed organization to sustain their competitive advantages by integrate the process with engineering, statistics and project management [5]. Numerous articles and books provide the basic concepts and benefits of the six-sigma methods [6-7]. Six-sigma applications in the service sector are still limited although it has been embraced by many big service oriented companies such as Lloyd, American Express, J.P. Morgan, ESB, Egg, Financial Services, Zurich, BT etc. The last decade has seen many service organizations such as Bank of America, Citibank, Caterpillar, Mount Carmel Health System and Baxter Healthcare in USA and Europe, success by sig sigma implementation [8-10].

Table 1 Motorola’s (six steps to six-sigma) Quality Improvement

Manufacturing

(Manufactured Product)

Non-Manufacturing

(Administration, Office, Service)

1. Physical and functional identification from voice of the customer

1. Identification of the product or service that is created and given to internal and external customers

2. Determine the essential characteristics of the product

2. Identify a product or service from the customer, and determine what customers consider important

3. Determine for each characteristic, whether it can be controlled by the process, part or controlled by both

3. Identify your needs (including needs of the supplier) to provide products or services so satisfy the customer

4. Determine the maximum coverage for each characteristic

4. Define the process for doing work (a process mapping)

5. Determine the variation on the process for each characteristic

5. Mistakes-proof processes and eliminate delays the work and efforts wasted

6. If the process capability (Cp) is less than two then do improvements on materials, products and processes required

6. Always continuous improvements by measuring, analyzing, and controlling the process improvements (build quality and cycle time measurement and improvement goals. Metrics commonly used is the number of defects per unit)

Sources: Motorola Material, Fukuda

The program presented in Table 1 describes that improvement action will be implemented in a project by project. It provides a clear organizational structure, in which improvement project are led by belt as black belt and green belt. To guide black belt and green belt activity, the program provides a methodology consisting of a collection of tools and stepwise strategy consist of five phase improvement cycle – DMAIC, within six-sigma companies has become increasingly common [11]. The goal of this paper is to review and examine lean and six-sigma practice and identify the key factors influencing successful lean and six-sigma. Therefore, this paper integrated lean and six-sigma project and potential applications in managing traditional projects. Wider application to the organization will succeed through senior management involvement, organizational commitment and culture change.

2. RESEARCH METHODOLOGY

The six-sigma method is often imagined as the breakthrough with five phases of DMAIC: Define-D, Measure-M, Analysis-A, Improve-I, and Control-C. It represents a problem solving methods “specifically designed to lead a six-sigma black belt to significant improvement within a defined process” [12, 7]. Thus, the aim of this paper is to identify the issues facing

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A Lean Six-Sigma Manufacturing Process Case Study

http://www.iaeme.com/IJMET/index.asp 500 [email protected]

and implement the lean and six-sigma in organization. In order to achieve the objective, the researcher used secondary data such as journals and documents, books, thesis, and scientific websites specialized in eliminating wastes.

Two sources were used to collect the primary data. First, wastes identification was implemented through a brainstorming session with some managers to answer seven wastes questions. The illustration and analysis are based on literature review and the answers of the brainstorming groups. Second, a questionnaire was distributed to the management of all of the manufacturing division having more than some employee, and member of the research team offloaded and analyzed the results and resolution through the use of the statistical procedure. The data collection in this study involves quantitative and qualitative methods. Using this approach, information can be generated from the practical issues in implementation of lean six-sigma. Some qualitative data were set on ten point scale, where 9 = extremely important, 7 = very important, 5 = important, 3 = somewhat important, and 1 = not important. Furthermore, the last step is to determine the weighting to calculate the ranking of importance.

3. LITERATURE REVIEW

3.1. Six-Sigma

Six-sigma is a systematic approach for improving manufacturing or service processes. Strengthen of six-sigma lies in its framework to facilitate the application of tools and techniques in a build data driven to support decision making [14-15]. The application of six-sigma was predominant in manufacturing process improvement. Recent developments show that its application is increasing in non-manufacturing operations such as transactional processes [16]. In order to apply six-sigma more broadly, need to introduce non-manufacturing that also involve processes. Identification of process parameters is one of the key to implementation of six-sigma in nonmanufacturing or service [17-18].

The success of six-sigma depends on certain success factors such as, top management commitment; tools and techniques; application of six-sigma methodology in DMAIC; and identification of KPIs such as financial impact measurement [19, 14]. Meanwhile, the statistical aspects of six-sigma must complement business perspective and challenges to the organization to implement six-sigma. Various approaches to six-sigma have been applied to increase the performance of different business sector. Integrating data and six-sigma processes in to organization still has room for improvement. Culture changes require time and strongly commitment before implanted into the organization [18]. Effective six-sigma principles and practices will more succeed by refining the organizational culture continuously. Six-sigma is a business improvement approach that seeking to find and eliminate causes of defects or mistakes in business processes by focusing on process output which critical in the eyes of customers. Six-sigma principles can be used to shifts the process average, help to create robust product and process and reduce excessive variation in process which lead to poor quality.

The term of sigma is a measure indicating the deviation in the performance characteristic from its mean performance. The basic goal of a six-sigma strategy is to reduce variation of performance characteristic. In order to improve the quality, it is imperative to measure or quality variation and then developed potential strategies to reduce variation. There are many literatures available on tools and techniques used in sig-sigma. Tools are mostly having a clearly defined role but narrow in focus, whereas techniques have wider application and require training, creativity and specific skill [1]. Some other literature provide classification scheme for tools and techniques used. Some researchers [3] discussed tool sets in three groups; statistical tools, process tools, and team tools. As for six-sigma tools and techniques

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Hari Supriyanto and Diesta Iva Maftuhah

http://www.iaeme.com/IJMET/index.asp 501 [email protected]

specific to service organization, a researcher [1] provides a guideline for service organization. The statistically based problem solving methodology of six sigma and process data can be used to generate solution. Table 2 represents the principles – strategies and technique – tools for six-sigma.

Table 2 Six-sigma principles – strategies and techniques – tools

Six-Sigma Principles and

Business Strategy Six-Sigma Techniques and Tools

Project management Statistical process control

Data-based decision making Process capability analysis

Knowledge discovery Measurement system analysis

Process control planning Design of experiment

Data collection tools and techniques Robust design

Variability reduction Quality function deployment

Belt system (Master, black, green, yellow) Failure mode and effects analysis

DMAIC process Regression analysis

Change management tools Analysis of means and variances, hypothesis testing, roots cause analysis, process mapping

Six-sigma is likely to remains as one of the key initiatives to improve the management process than just being remembered as one of the fads [20]. The primary focus should be on improving overall management performance, not just counting defects. Integrating between principles and characteristics of six-sigma with Human Recourse Functions [21]; Total Quality Management [22-23]; Lean Production [24]; ISO 9000 [25]; ISO 9001 [26], everything are efforts to optimize the positive effect of the six-sigma principles.

The key indicator and success for the effective implementation and introduction of six-sigma in UK manufacturing and services organizations have been revealed as the following; understanding of six-sigma methodology; management involvement and commitment; tools and techniques; linking six-sigma to customer; linking six-sigma to business strategy; projects selection; organizational infrastructure; review and tracking; linking six-sigma to supplier; culture change; projects management skill and training [19]. However, other researchers [20] provides useful implementation tips for successful six-sigma application, such as continuing training and education of participants and managers, visible and sustained commitment management, selecting project leaders and setting clear expectations, leadership skill, selecting and picking strategically important projects. The following Table 3 represents saving and benefits from six-sigma in manufacturing sector.

Table 3 Savings and benefits from six-sigma in manufacturing sector [27,19, 28]

Company / Project Metric Measure Benefits Savings

Motorola (1992) In process defect levels 150 time reduction

Raytheon / aircraft integration system

Depot maintenance inspection time

88 % reduction measured in days

Business / GE Railcar lease turnaround time in the shop

Reductions up to 62 %

Allied signal (Honeywell) / lamination plant in South Carolina

Capacity Cycle time Inventory On-time delivery

Up 50 % Decrease 50 % Decrease 50 % Increase approaching 100 %

Allied signal (Honeywell) / Bendix IQ brake pads

Concept-to-delivery cycle time

Reduced from 18 months to 8 months

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Hughes aircraft missile systems group / wave solder operation

Quality / productivity Improved 1.000 % / improved 500 %

General Electric Finance $ 2 billion in 1999

Motorola (1999) Finance $ 15 billion over 11 years

Dow Chemical Projects / rail shipments

Finance Saving more than $ 2.45 million for capital expenditure

DuPont plant / Yerkes in New York (2000)

Finance Savings more than $ 25 million

Telefonica de Espana (2001) Finance Savings and increased revenue of 30 million euros in the first 10 months

Texas Instrument Finance $ 600 million

Johnson and Johnson Finance $ 500 million

Honeywell Finance $ 1.2 billion

3.2. Lean Thinking (LT)

The concept of lean thinking developed from Toyota Production System-TPS with identifying the value of a long process and steps eliminating waste by way of sorting out and getting rid of non-value added activities against value added activities. Lean focuses on efficiency to produce products and services as fast as possible and at lowest cost. The top management should begin first to commit against LT and should deploy and exert efforts down to various levels to improve processes flow and efficiency. Lean strategy brings a set of proven techniques and tools to reduce set up times, inventories, lead times, equipment down times, scraps, another hidden and invisible wastes in the process [29].

Lean Production or Lean Thinking has the philosophy to achieve improvements in most economical ways with focus on reducing waste [30-31]. The concept of waste became one of the most important concepts in quality improvement activities and the first idea by Taiichi Ohno’s famous production philosophy from Toyota in the early 1990s [32]. This philosophy was furthermore called as Toyota Production System-TPS in Japan and in 1986 named as Lean Production and Lean Thinking [30].

One of the experts on quality control [33] might be the first to deal with the different forms of wastes. Furthermore, reduction and identification of waste have become one of the main activities in quality improvement. This identification of waste is called the Cost of Poor Quality (COPQ).

3.3. Lean Six-Sigma

Lean is primary focus on information and build value adding with in along the process steps whereas six- sigma can be helpful in handling poor performing. Many lean principles are fundamentally base on qualitative models and developed from a long research. Six-sigma on other hand can play a critical role in understanding what is happening inside the process steps. Figure 1 shows the strong relationship between lean and six-sigma to increase organizational performance.

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Figure 1

Lean and six-sigma will lead to business competitiveness and quality improvement. Theapplication of both lean and sixapplications. Lean and six-sigma both are emphasiswaste on process flow and the thinking is to increase productivity by incand reduce cycle time. Six-variations. It can be seen at Figure 2 describing defect rate (DPMO)value. Lean focuses on reduction of cost by eliminating all sortor wastes. Six-sigma focuses on reduction of cost by systematically sorting cost of poor quality items in along processes.

Figure 2

Some of similarities between lean and siimprovement, such as both methodologies are focusing to business need and customers need; both are process centric and process focus; both concept need multirequire management support fo[29].

4. CASE STUDY AND RESUL

A case study is presented and taken where systematically the control process of manufacturing will be improved by applying of lean sixjoined and eliminated by reduction the down time process and as simultaneouslysteps included the systematic approach of the current state through walking alongdefining a realistic target to reach the ideal state; preparing the process map to inefficiencies and quantity waste; and implementing the improvement actions

Lean speed enables six

quality

Hari Supriyanto and Diesta Iva Maftuhah

IJMET/index.asp 503 [email protected]

Figure 1 Relationship between lean and six-sigma

sigma will lead to business competitiveness and quality improvement. Theapplication of both lean and six-sigma require learning of various techniques, tools and the

sigma both are emphasis of process flow. Lean focuses minimum waste on process flow and the thinking is to increase productivity by increasing how to work

-sigma focuses on process flow and pressure to minimum It can be seen at Figure 2 describing defect rate (DPMO) as an input for sigma

Lean focuses on reduction of cost by eliminating all sorts of non-value adding activities sigma focuses on reduction of cost by systematically sorting cost of poor

quality items in along processes.

Figure 2 Defect rate (DPMO) and sigma value

Some of similarities between lean and six-sigma approaches to process management and such as both methodologies are focusing to business need and customers need;

both are process centric and process focus; both concept need multi-disciplinary team; both require management support for success; both can be used in non-manufacturing or service

CASE STUDY AND RESULT

A case study is presented and taken where systematically the control process of manufacturing will be improved by applying of lean six-sigma methodologies. Waste was

reduction the down time with implement the change of working simultaneously reducing the variation of along business process

steps included the systematic approach of the current state through walking alongdefining a realistic target to reach the ideal state; preparing the process map to inefficiencies and quantity waste; and implementing the improvement actions [34].

Lean speed enables six-sigma

Six-sigma quality enables lean

speed

[email protected]

sigma will lead to business competitiveness and quality improvement. The sigma require learning of various techniques, tools and the

process flow. Lean focuses minimum reasing how to work

sigma focuses on process flow and pressure to minimum as an input for sigma value adding activities

sigma focuses on reduction of cost by systematically sorting cost of poor

sigma approaches to process management and such as both methodologies are focusing to business need and customers need;

disciplinary team; both manufacturing or service

A case study is presented and taken where systematically the control process of sigma methodologies. Waste was

with implement the change of working reducing the variation of along business process. The LSS

steps included the systematic approach of the current state through walking along process; defining a realistic target to reach the ideal state; preparing the process map to inefficiencies

The questionnaire

sigma quality enables lean

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A Lean Six

http://www.iaeme.com/IJMET/index.

survey was designed and used to helpsteps are to conduct in-depth case study. Case study approach helps in developing a theory which is better grounded, more gselected and based on the idea of theoretical sapreferable [36].

The manufacturer of gas stove is the the activity hence, types of activities are classified itypes, such as value added (VA), necessary but non value added added (NVA) [37].

Figure 3

Based on a long process and overall activity that flow along the production processis 23.3 % value adding activity and well as 43.52 % is non-value addpeppered throughout the production process flow.must be identified more depth to know the type of wasteon the surface. Non value adding activity is an activity that causes waste. There are seven commonly accepted wastes ioverproduction, (2) waiting, (3) transportation, (4) inappropriate processing, (5) unnecessary inventory, (6) unnecessary motionthe weight of each waste so can be calculated and viewed the highighest ranking means that it needs ththis case are the defect, inappropriate and wa

A Lean Six-Sigma Manufacturing Process Case Study

IJMET/index.asp 504 [email protected]

used to help in understanding of six-sigma in organization. The next depth case study. Case study approach helps in developing a theory

which is better grounded, more generalizable and more accurate [35]. The case study is selected and based on the idea of theoretical sampling. In this case, theoretical sampling

The manufacturer of gas stove is the case study company. Based on the identification of the activity hence, types of activities are classified in the manufacture of gas stove

value added (VA), necessary but non value added (NNVA),

Figure 3 Value Stream mapping of product

a long process and overall activity that flow along the production processivity and 35.19 % is necessary but non value add

value adding activity. It shows that there are still a lot of waste that are peppered throughout the production process flow. Therefore the non-value added activity

t be identified more depth to know the type of wastes that is hidden and does not appear Non value adding activity is an activity that causes waste. There are seven

commonly accepted wastes in Toyota Production System-TPS [38-overproduction, (2) waiting, (3) transportation, (4) inappropriate processing, (5) unnecessary inventory, (6) unnecessary motion, and (7) defects. The following Table 4 the weight of each waste so can be calculated and viewed the highest ranking to lowest

it needs the attention from the management to do improvements in nappropriate and waiting waste.

[email protected]

gma in organization. The next depth case study. Case study approach helps in developing a theory

. The case study is theoretical sampling is

. Based on the identification of n the manufacture of gas stove into three

VA), and non-value

a long process and overall activity that flow along the production process, there necessary but non value adding activity, as

It shows that there are still a lot of waste that are value added activity

that is hidden and does not appear Non value adding activity is an activity that causes waste. There are seven

-39], such as (1) overproduction, (2) waiting, (3) transportation, (4) inappropriate processing, (5) unnecessary

shows qualitatively hest ranking to lowest. The

o do improvements in

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Hari Supriyanto and Diesta Iva Maftuhah

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Table 4 Seven wastes

No. Waste Score

Total Ranking 1 2 3 4 5 6 7 8 9

1 Overproduction

1 2 1 1 23 4

2 Waiting 4 1 24 3

3 Transportation 3 1 1 7 7

4 Inappropriate Processing 2 1 1 25 2

5 Unnecessary Inventory 2 2 1 23 5

6 Unnecessary Motion 2 2 1 14 6

7 Defects 1 1 1 2 28 1

Weighted 8 7 6 5 4 3 2 1 0

Each row shows a certain wastes and on the seven other wastes; similarly each column shows the degree of interest which is filled by the management as expert judgment. Furthermore, each field of management multiplied by the weight indicated on bottom row. The weights of each row and column were added to obtain total score. The result of the multiplication in form the total of each wastes, then retrieved the ranking of waste from highly risky (1) until the riskless (7). In seven types of waste as calculated and weighted seen that the highest weight is on defect waste. This waste connected directly with defects per million opportunities (DPMO) as input to calculate the value of sigma. Based on the identification of defects and critical to quality-CTQ, types of non-conforming that cause its defects waste can be obtained. CTQ can be used as basis for generating alternative solutions. CTQ in defect waste and waiting waste can be seen in Table 5.

Table 5 Critical to quality in defect waste and waiting waste

Critical to Quality (CTQ) in defect waste Critical to Quality (CTQ) in waiting

waste

1. paint defective: uneven paint and bubbly 1. delay material and not within specifications

2. rivet defective: the hole is too big / small and not within specifications

2. The engine stopped and the damage

3. deformed body: body dents and require reprocessing

3. rework process

Meanwhile, based on CTQ, DPMO as an input for sigma value can be seen in following Table 6.

Table 6 DPMO and Sigma value

Period Production (Unit) Defect (Unit) DPMO Sigma

Value

1 70007 2182 15584 3.7

2 58544 1668 14246 3.7

3 119081 3900 16375 3.6

According to the data defective products above, thereafter for each period can be shown the amount of each types of non-conforming shown in table 7.

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Table 7 The types and amount of nonconforming of gas stove

Type of

Nonconforming

Amount (Unit)

Rivet 2773

Body 1878

Paint 1784

Burner 1315

Based on the types of nonconforming, it can be seen that the highest nonconforming contained in the type of rivet and body which causes body to be damage or product defects. The second waste was inappropriate processing. This waste that cause defect products. Which causes inappropriate processing is inaccuracy in the process of blanking machine, the machine that makes holes for process of joining by using the process of the rivet. The third waste is waiting waste. Waiting waste is a certain amount of time when operator does not use the time to perform value added activities due to waiting for flow of products from the previous process. The indication of waiting on the production process is stated by downtime caused by the machine breakdown. Machine downtime is influenced by several factor such as cleaning, waiting for the material, change tools, the machine is done setting, power failure, maintenance and broken machine,

However, based on the first waste, it can be concluded that a defect and / or nonconformities are caused by the waste that is inappropriate processing waste. The process associated with this defect is blanking process. One reason for the failure is the blanking punch pressure-less; and this is caused the electric power lacking. The emergence of these wastes will result in waste of waiting. This waste gives an indication of the long lead time, and causing a decline in production capacity. Another consequence is the decline in productivity. Furthermore, alternative solutions can be degenerated based on such wastes which is described in Table 8.

Table 8 Alternatives solution

Sub Waste Effect Root Cause Improvement

Breakdown Machine Power Failure Less Electrical Power Raise The Power

Rivet Defective

Operator Error Operators Are Not Careful

Improvement Of Inspection

Hole Processing Errors

Limited Number Of Jig Fixture

The Addition Of Jig Fixture

Body Defective The Body Scratched There Are No A Protective

Provide A Protective Layer

5. CONCLUSIONS

Implementation in lean six-sigma have been proved and success in the last few years. It is becoming a main driving force for technology driven and project driven. Factors influencing successful lean six-sigma projects include management involvement and organization commitment, project management and control skill, continuous training, and culture change. Tracing some of shortcomings, key indicators and weakness of six-sigma gives opportunities for implement lean six-sigma project. It allows better support for strategic and direction, and improving needs for mentoring, training and coaching. Contributing to the development of a lean six-sigma conceptual framework, where the main objective of six-sigma is reducing variation and that of lean is reducing cycle time. This paper presents the application of lean

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methodologies to eliminate waste in along the process and to reduce defect to increasing sigma value.

Lean six-sigma has been proved as structured methodology to improve organizational processes. With focus on customer and systematically translate critical to quality characteristics into improvement project so the success of the organization will be realized. It can be said that lean six-sigma programs enable organization to become more creative through dual focus on efficiency and continuous improvement. In addition, as firms that take advantage on lean six-sigma programs, monitoring, ability in identifying, and finding the needs of future customers maybe dreadfully required.

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[3] Henderson, K. H. and Evans, J.R. Successful Implementation of Six-Sigma: Benchmarking General Electric Company, Benchmarking. An International Journal, 7 (4), 2000, pp. 260-281.

[4] Basu, R. Implementing Quality: A Practical Guide to Tools and Techniques: Enabling the Power of Operational Excellence. London: Thomson Learning, 2004.

[5] Anbari, F. T. Six-sigma Methods and Its Applications in Project Management. Proceeding of the Project Management Institute Annual Seminar and Symposium, San Antonio, Texas, 2002.

[6] Harry, M. J. and Schroeder, R. Six-sigma: The Breakthrough Strategy Revolutionizing the World’s Top Corporation. New York: Doubleday, 2000.

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