A literature view on the application of failure mode ...

Int. J. Value Chain Management, Vol. 5, Nos. 3/4, 2011

A literature view on the application of failure mode and effects analysis in tea industry I. Alfred Ebenezer* and S.R. Devadasan Department of Production Engineering, PSG College of Technology, Coimbatore – 647 004, Tamil Nadu, India E-mail: [email protected] E-mail: [email protected] *Corresponding author

C.G. Sreenivasa Department of Industrial and Production Engineering, University B.D.T College of Engineering, Davangere – 577 004, Karnataka, India E-mail: [email protected]

Päivi Iskanius Department of Industrial Engineering and Management, Faculty of Technology, University of Oulu, P.O Box. 4610, 90014, Oulu, Finland Fax: + 358-8-553-2904 E-mail: [email protected] Abstract: This paper reports a literature survey which has been carried out to study the application of failure mode and effects analysis (FMEA) technique in tea industry. The first phase of this literature survey indicated that so far no researches on the application of failure analysis techniques likes FMEA in tea industry have been conducted. Meanwhile, it was observed that a few advanced models of FMEA have appeared in literature. The salient features of these advanced models of FMEA which were drawn from literature arena have been presented in this paper. The paper has been concluded by suggesting that due to its simplicity and holistic approach, total failure mode and effects analysis (TFMEA) would be a right advanced technique of FMEA for application in tea industry. Keywords: tea industry; total quality management; TQM; failure mode and effects analysis; FMEA; literature survey; failure analysis. Reference to this paper should be made as follows: Ebenezer, I.A., Devadasan, S.R, Sreenivasa, C.G. and Iskanius, P. (2011) ‘A literature view on the application of failure mode and effects analysis in tea industry’, Int. J. Value Chain Management, Vol. 5, Nos. 3/4, pp.251–264.

Copyright © 2011 Inderscience Enterprises Ltd.

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I.A. Ebenezer et al. Biographical notes: I. Alfred Ebenezer is the Principal of NPA Centenary Polytechnic College, Kotagiri, Nilgiris, Tamilnadu, India. He is currently pursuing his PhD in the Production Engineering Department of PSG College of Technology, Coimbatore, India. He holds a Bachelor’s degree in Mechanical Engineering and a Master’s degree in Production Engineering. He has 20 years of teaching experience. His research interests include TQM and failure analysis. S.R. Devadasan is a Professor in the Production Engineering Department of PSG College of Technology, Coimbatore, India. He holds a Bachelor’s degree in Mechanical Engineering, a Master’s degree in Industrial Engineering, a PhD in Mechanical Engineering and a Doctor of Science degree in Mechanical Engineering. He has 20 years of teaching and research experience. He has published over 88 papers in international journals. He is an editorial advisory board member of the European Journal of Innovation Management and a review board member of the Journal of Management Development. His research interests include agile manufacturing, Six Sigma and total productive maintenance. C.G. Sreenivasa is an Assistant Professor in the Department of Industrial and Production Engineering of the University B.D.T College of Engineering, Davangere, Karnataka (State), India. He holds a Bachelor’s degree in Mechanical Engineering and a Master’s degree in Production Engineering System Technology. He has eight years of teaching and research experience. He has participated and presented papers in seven international and national conferences. Three of his research papers have been published, seven papers have been provisionally accepted and five papers have been communicated for publication in international journals. His area of interest includes agile manufacturing, lean manufacturing and industrial engineering. Päivi Iskanius is a Project Manager at the University of Oulu, Thule Institute. She coordinates the Northern Research and Innovation Platform Project. She has received her MA in Mechanical Engineering in 1988, eMBA in 2002, Licentiate’s degree in Mechanical Engineering in 2004 and PhD in Industrial Engineering and Management in 2006. All of these degrees are from the University of Oulu. Her research interests are logistics, supply chain management and e-business applications in the business networks, and further, innovation systems and networks and processes. Currently, she has over 90 research publications in these areas.

1

Introduction

Right from the olden days, man had been consuming several beverages. Tea is one of the widely consumed beverages by man (Alkan et al., 2009; Liu et al., 2010). Tea is largely used as a sign of hospitality. Nearly two-third of the world’s population drink tea and it is next only to water in its consumption as a beverage. Tea is also an important antioxidant agent which is believed to prevent a wide range of ailments like cancer and heart diseases (Sinija et al., 2007; Chen et al., 2009; Ravichandran, 2004). Tea is predominantly manufactured in countries such as India, China, Sri Lanka and Kenya. There has been a stiff competition among these countries to conquer the international tea

A literature view on the application of failure mode and effects analysis

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market. One of the strategies adopted by these countries to face the competition is the infusing of high degree of quality in the tea produced by them. Besides aiding to face competition, quality of the tea influences the prices (Ravichandran, 2004). Under these circumstances, food technocrats and agronomists have been striving to identify solutions for improving quality of tea. Though it appears as through only the food technocrats can contribute towards the improvement of quality of tea, it is a fact that engineers have a significant role to play in the manufacturing of tea (Temple et al., 2000). This is due to the reason that, the manufacturing processes of tea are developed through the design, production and operations of equipment which fall under the purview of various disciplines of engineering. These manufacturing processes influence the quality of tea to a great extent. The failure to manufacture tea with high quality results in losing of sales too. As food technocrats have been studying the various chemical compositions of the raw material and its implication on the quality of tea, it is felt that engineers can contribute significantly in the manufacturing and engineering aspects of tea to enhance its quality. Though the tea industry has realised the importance of infusing high degree of quality to face the ever increasing competition, there has been a lack of knowledge in the total quality management (TQM) concepts which have been used in other industries worldwide to produce high quality products and services. The need of the hour is that, this research and practice gap needs to be filled by applying the techniques adopted in TQM field in the manufacturing of tea. TQM addresses the concept of ‘continuous quality improvement’. Continuous quality improvement results in improved productivity by eliminating defects, non-value adding activities and rework. Improving quality continuously also leads to the reduction of cycle time and machine time. It is felt that TQM concepts if implemented in tea industry will eliminate failures and thereby produce high quality tea which will fetch higher prices in the international market. Under these circumstances, failure analysis concepts need to be implemented to prevent the manufacturing of low quality tea. The field of TQM has largely employed failure mode and effects analysis (FMEA) technique to carry out failure analysis in several fields (Tay and Lim, 2006). Meanwhile, some researchers have advocated the deployment of advanced versions of FMEA (Pillay and Wang, 2003). Therefore, it becomes important to explore the implementation of FMEA and its advanced versions in tea industry. In this context, literature was surveyed to identify the potential of applying FMEA and its improved versions in tea industry. The details of this literature survey have been presented in this paper.

2

Literature survey methodology

The literature survey reported in this paper was carried out by gathering articles on tea industry and failure analysis in TQM field. The articles were gathered mainly from two databases namely Emerald insight (www.emeraldinsight.com) and Science Direct (www.sciencedirect.com). Articles on tea manufacturing were also gathered from Krishi Vigyan Kendra (KVK), United Planters Association of South India (UPASI) situated in Coonoor, Tamil Nadu State, India. The literature thus gathered were systematically surveyed by following the methodology depicted in Figure 1.

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Figure 1

Literature survey methodology

Literature survey on tea industry Search to identify the application of failure analysis in tea industry

Literature survey on failure analysis in TQM field

Identification of TFMEA as the most practically compatible model for application in tea industry As shown, during the first stage of the literature survey, the researches on tea industry were surveyed. During the second stage of the literature survey, the trend of researches on failure analysis in tea industry was studied by surveying the literature. This survey revealed that no research on applying failure analysis techniques like FMEA in tea industry has so far been reported in literature. In this context, the literature was searched in TQM domain to study the researches on failure analysis. During this stage, the techniques adopted in TQM field to carry out failure analysis were identified. Followed by that, a search was made to study the application of any of these techniques in tea industry for the purpose of exercising continuous quality improvement. During the fourth stage of literature survey, the results were analysed. This analysis favoured the study of applying the technique total failure mode and effect analysis (TFMEA) in tea industry.

3

Researches on tea

The literature survey on the researches on tea was conducted from three perspectives. From the first perspective, the global trend of carrying out researches on tea was surveyed. From the second perspective, the beneficial aspects of tea as reported in literature arena were studied. From the third perspective, the factors influencing the quality in the manufacturing of tea were studied. These details are briefly presented in the following three subsections.

3.1 Global trend of researches on tea The literature was surveyed to trace the global trend of researches on tea by locating the researches on tea conducted in various countries. The listing of countries where researches on tea have been conducted and the papers that have reported them are presented in Table 1.

A literature view on the application of failure mode and effects analysis Table 1 Serial number

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Global trend of researches on tea Countries in which researches have been conducted on tea

Papers reporting the researches on tea

1

Japan

Tanaka et al. (2002)

2

India

Mohapatra et al. (1984), Ravichandran (2004), Kumar et al. (2004), Sinija et al. (2007), Mohanpuria et al. (2009) and Sharangi (2009)

3

USA

Yang et al.(2007), Weisburger (1997), Lambert and Yang (2003) and Hou et al. (2004)

4

Germany

Sohie et al.(2009)

5

UK

Hamer (2007)

6

Mauritius

Ramma et al. (2005)

7

Norway

Nurk et al.(2009)

8

China

Liang et al. (2009), Chen et al. (2006, 2009) and Zhang (2002)

9

Malawi (Central Africa)

Tomlins and Mashingaidze (1997) and Temple et al. (2000, 2001)

10

Thailand

Suteerapataranon et al. (2009)

11

Korea

Wang et al. (2008)

12

Kenya

Owuor and Obanda (1999, 2001)

13

Canada

Dufresne and Farnworth (2001)

As shown the researches on tea are conducted in about 13 countries in the world. This small number may be attributed to the reason that tea plants can be cultivated only in certain countries. Nevertheless, the participation of only few countries in researches in tea is an indication that the role played by the selling of tea in international market is yet to be fully realised by the world community.

3.2 Beneficial aspects of drinking tea The beneficial effects of drinking tea in improving health and preventing various diseases addressed by the researches are enumerated in Table 2. A majority of researchers have focused their attention on the effect of tea in preventing cancer. It is understood that antioxidants such as those present in tea can play an important role in prevention and also control of cancer (Dufresne and Farnworth, 2001; Yang et al., 2007). Researchers have claimed that drinking green tea can reduce blood glucose levels and hence can aid in controlling diabetes. It is also reported that tea can improve gastrointestinal function, aid in healing kidneys, liver, panaceas and stomach injuries, protect skin and eyes, improve oral health, prevent infections and aid in healing other diseases that have an inflammation component. It is also claimed that drinking tea helps in improving the neurological and psychological health of a person. At present, even though there prevails no conclusive proof that tea is a health drink, the quantum of research on the beneficial effects of tea is on the increase (Dufresne and Farnworth, 2001).

256 Table 2 Serial number

I.A. Ebenezer et al. Beneficial aspects of drinking tea Beneficial effect of drinking tea

Paper reporting the topic

1

Role of drinking tea in cancer prevention

Yang et al. (2007), Zhang et al. (2002), Lambert and Yang (2003) and Hou et al. (2004)

2

Influence of drinking tea in treating obesity related diseases

Sohie et al. (2009)

3

Influence of drinking tea in improving cognitive performance

Nurk et al. (2009)

4

Influence of drinking tea in stroke prevention and coronary heart disease

Liang et al. (2009) and Ramma et al. (2005)

5

Influence of drinking tea is boosting attention span

http://www.nutraingredients.com

6

Beneficial effects of drinking tea on immune function

Hamer (2007)

7

Role of drinking tea in health promotion

Weisburger (1997) and Dufresne and Farnworth (2001)

3.3 Factors influencing quality of tea With the increase in the demand for tea, various national and international authorities are setting numerous quality standards (Chen et al., 2006; Estorilio and Posso, 2010). The major tea producing countries like India, have realised the need for producing high quality tea in order to fetch better prices and also to be competitive in the international market (Mohapatra et al., 1984; Ravichandran, 2004). Tea is manufactured from the young tender shoots of the plant called Camellia sinensis. The quality of manufactured tea depends mainly on two important major factors namely the shoots used and the manufacturing process. The derivations of the various researches regarding the quality aspect of tea are enumerated is Table 3. Table 3 Serial number

Factors influencing the quality of tea Factors influencing the quality of tea

Papers reporting the factors

1

Plucking standard of green leaf

Owuor and Obanda (2001) and Ravichandran (2004)

2

Impact of pruning and time between successive pruning on quality

Ravichandran (2004)

3

Influence of withering, including leaf handling

Tomlins and Mashingaiuge (1997)

4

Influence of temperature and duration of fermentation.

Owuor and Obanda (2001)

5

Maintaining proper drying time and temperature

Temple et al. (2000)


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The analysis of literature survey has revealed the fact that quality of tea manufactured depends on the quality of tea leaves harvested and thereby the quality starts from the field from where the green leaf is harvested. The normal plucking standard recommended to produce good quality tea is large quantity of two leaves and a bud, and small quantity of three leaves and a bud (Owuor and Obanda, 2001; Ravichandran, 2004). Withering plays an important role in the quality of tea. Moreover it is also pointed out that a substantial percentage of the market value of tea may be lost if the green leaf is not properly handled while transporting it from the field to the factory (Tomlins and Mastingaidze, 1997). Researchers have also mentioned that pruning plays an important role in ensuring the quality of shoots harvested (Ravichandaran, 2004). It is also established that various other stages in tea manufacturing such as maceration or rolling, fermentation and drying have an influence on the quality of tea manufactured.

4

Failure analysis models in TQM

During the past 50 years, various theories on TQM have emerged. TQM emphasises upon continuous quality improvement through failure identification and rectification. Before the evolution of TQM principles, the scope of the term failure was restricted only to product failures. However the TQM principles view failures as those caused in products, processes, services and throughout the system. TQM professionals have been propagating two techniques namely FMEA and fault tree analysis (FTA) for attaining continuous quality improvement through failure identification and rectification (Devadasan et al., 2003). Of these two techniques, FMEA has penetrated the organisational scenario to some extent. FMEA is an established failure analysis technique that also reports fault tolerant design, testability, safety, logistic support and related functions. The purpose of applying FMEA is to analyse the design characteristics relative to the planned manufacturing process for ensuring that the resultant product meets customer needs and expectations (Devadasan et al., 2003; Sharma and Sharma, 2010). When potential failure modes are identified, corrective action can be taken to eliminate or continually reduce the potential for occurrence. FMEA provides an organised critical analysis of potential failure modes of the system being defined and identifies associated causes. It uses occurrence and detection probabilities in conjunction with severity criteria to develop a risk priority number (RPN) (Tay and Lim, 2006; Sharma and Sharma, 2010). A brief study of the literature on FMEA indicated that though FMEA technique is a powerful tool for failure prevention, it suffers from certain deficiencies (Chin et al., 2009; Arabian-Hoseynabadi et al., 2010). Particularly, it was discernable that, the traditional FMEA processes is not exhaustive and hence, does not contribute towards failure prevention holistically. Under these circumstances various, advanced models on FMEA have been brought out by the researchers (Pillay and Wang, 2003). A list of some of the advanced models of FMEA are indicated in Table 4. A perusal of the contents of Table 4 would indicate that a few new techniques have been adopted by the by researchers to overcome the deficiencies of the traditional FMEA. A few researchers have applied fuzzy logic and fuzzy inference techniques to enhance the failure risk evaluation and prioritisation capabilities of FMEA (Tay and Lim, 2006; Pillay and Wang, 2003). In Wang et al. (2009), instead of

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using fuzzy if-then rules, another model has been proposed using fuzzy weighted geometric mean. Ahsen (2008) has developed an improved model called cost-oriented FMEA where the severity of failures is expressed in terms of costs. Colvin et al. (2008) have suggested a new approach for supporting FMEA for time-critical systems, which has been named as timed FMEA. This model is capable of investigating timing failures. Table 4 Serial number

Advanced models of FMEA Name of the advanced FMEA model

Papers in which the advanced model has appeared

1

TFMEA programme

Devadasan et al. (2003)

2

Fuzzy FMEA with a guided rules reduction system for prioritisation of failures

Tay and Lim (2006)

3

Cost-oriented FMEA

Ahsen (2008)

4

Timed FMEA

Colvin et al. (2008)

5

Automated multiple failure FMEA

Price and Tailor (2002)

6

Risk evaluation in FMEA using fuzzy weighted geometric mean

Wang et al. (2009)

7

FMEA by data development analysis

Chin et al. (2009)

8

Modified FMEA using approximate reasoning

Pillay and Wang (2003)

9

FMEA through knowledge modelling

Teoh and Case (2004)

10

Tool support for incremental FMEA of component-based systems

Elmquist and Tehrani (2008)

Chin et al. (2009) have proposed a FMEA model which uses data envelopment analysis to determine the risk priorities of the failure modes. In this method, the maximum and minimum risk of each failure mode is measured. The maximum and minimum risk values are geometrically averaged to measure the overall risks of failure modes. Teoh and Case (2004) have developed a model which attempts to make use knowledge on FMEA through a knowledge modelling approach. Functional reasoning techniques are used to assist this FMEA model to enable the generation of FMEA automatically from historical data. Price and Taylor (2002) have designed a model called Automated multiple failure FMEA. This model enables to carry out the analysis of a large number of failure combinations but provides the engineers with only those combinations that lead to the derivation of interesting results. Devadasan et al. (2003) have contributed the advanced model called TFMEA. TQM emphasises the integration of all the departments of an organisation but the traditional FMEA is generally applied only to the design and production processes. Moreover conventional FMEA uses a complex procedure to calculate the RPN. RPN is used for estimating the mode and effect of the failures. Though the process of calculating RPN is complex, it is not very accurate (Chin et al., 2009). TFMEA overcomes these deficiencies (Devadasan et al., 2003). In this context it was decided to explore the features of TFMEA and its application potential in tea industry.

Over heating of tea

Case hardening

Burnt taste of tea and loss of quality

Effects of failure

Notes: M – mechanical engineering, Q – quality control

Cause of failure

Failure mode

:

Members present

TFMEA table for production department

: Drying :1

TMFEA number

Date

Present control 8

Rating

Updated by

Last updated on

M, Q

Departments

:

:

:

Recommended activities

Approved by

Table 5

Process name

A literature view on the application of failure mode and effects analysis TFMEA – production

259

260

5


Features of TFMEA

The term ‘total’ in TFMEA refers to two significant meanings. First TFMEA calls for preventing failures that originate not only from design and production departments, but also from all other departments functioning in the organisation. This ensures totality in identifying, analysing, rectifying and preventing the recurrence of failures. Second, TFMEA calls for associating all the departments while analysing and rectifying each failure. These two aspects are fulfilled by developing TFMEA table. These aspects are depicted in Figure 2. Figure 2

Framework of TFMEA

TFMEA – M

TFMEA – P

TFMEA – E

TFMEA – S

TFMEA – Q

TFMEA cards

TFMEA – A

Notes: M – mechanical engineering S – sales and marketing P – production process Q – quality control E – electrical engineering A – accounts and finance

The format of TFMEA table is shown in Table 5. As shown, in the case of TFMEA table, the RPN is replaced by rating. This replacement overcomes the criticism on RPN reported in the literature. Furthermore, the associated departments are indicated in TFMEA table. This triggers the spontaneous participation of representatives from the associating departments as a team in the concerned TFMEA project. TFMEA table is required to be prepared in all associating departments and the rating with respect to each department needs to be indicated. This framework of TFMEA ensures that each failure is prevented from recurrence from a total point of view of the organisation.

6

Potential of TFMEA application in tea industry

Tea manufacturing industry involves core engineering activities and hence TQM and other quality engineering concepts implemented in major manufacturing industries can be


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applied in tea industry to reap the same benefits. Tea industry is labour intensive and most of the labours involved are not knowledgeable to scientifically analyse and point out the causes of quality failures in the manufacturing of tea. TFMEA is a simple, effective and holistic technique and hence, it can be easily implemented in tea Industry. Under these circumstances, it is opined that TFMEA technique if implemented in tea industry will help to identify and prevent failures and thus aid in improving the quality and reducing the cost of tea manufacturing.

7

Conclusions

Tea manufacturing involves major engineering activities, but rarely engineers have shown interest to contribute technologies for enhancing the quality of tea. Particularly TQM does not find applications in tea industry. Upon realising this research and practice gap, the literature survey reported in this paper was carried out. The scope of this literature survey was restricted to study any researches that have been conducted in tea industry for filling the research and practice gap involving the failure analysis. The field of TQM has predominantly applied FMEA techniques to carry out failure analysis. The results of this literature survey indicated a research gap in the form of absence of any research dealing with the application of FMEA in tea industry. Meanwhile, it was found that a number of advanced models of FMEA have emerged in literature. After studying those models, due to its simplicity and holistic capability, TFMEA has been suggested for carrying out failure analysis in tea industry. On the whole, this paper is concluded by citing the application of TFMEA in tea industry as the missing research domain and filling this research domain will aid tea industry to continuously improve the quality of tea and achieve core competitiveness. The literature survey reported in this paper suffered from a limitation. This limitation is the absence of researches reported by TQM professionals dealing with the continuous quality improvement of tea. Hence, engineering and management oriented data on infusing higher degree of quality in the manufacturing of tea using TQM techniques could not be surveyed in literature. This limitation can be overcome by conducting researches in tea industry from the perspectives of implementing TQM techniques and tools. This implies that, in future researches shall be conducted by implementing most advanced TQM techniques like TFMEA in tea industry. Using the experience and knowledge gained by implementing these most advanced techniques, the TQM journey of tea industry has to be accelerated for producing high quality tea.

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