Toward a structured approach for the integration of Lifecycle

Toward a structured approach for the integration of Lifecycle Requirements in Quality Management Systems Matteo M. Savino*, Gaetano Nicchiniello* and Abdelaziz Bouras** *

Department of Engineering, University of Sannio - Piazza Roma, 21 – 82100 Benevento, Italy [email protected] [currently visiting Prof. at University of Lyon] **

University of Lyon, Lyon II, LIESP Lab - 160 Bd de l’Université 69676 Bron Cedex, France [email protected]

1. Abstract The fast and continuous markets’ change and the growing needs of product quality and efficiency during the entire lifecycle require deep transformations in terms of product quality and quality management. In this context, enterprises should consider a continuous Customer Satisfaction, optimising the entire product lifecycle to be sure to remain competitive in the global worldwide market. In order to carry out these objectives, it is necessary to manage, in a structured way, all the activities that constitute the core processes of engineering, production, product distribution embedded with their Quality Management Systems -QMS (Dilani et al., 2002). This becomes possible through the application of the Lifecycle Management point of view (PLM) thanks to which we identify a model of business target, from a perspective of the organization and processes management. The proposed work aims at realizing a structured approach, able to embed the actions to be done to establish a Lifecycle Management point of view inside a QMS of a certain enterprise. In particular, the proposed approach considers the operative lifecycle actions, in terms of procedures and modules, to be provided in a QMS. The first part of the work highlights the lifecycle functions and analyses them through some existing approaches. In the second part, a structured set of actions for the integration of the Lifecycle point of view in a QMS system is proposed for the maintenance phase. The developed methodology has been applied in a enterprise producing power generators where a certified QMS system was already in use. The measurement of the benefits related to the lifecycle integration has been concentrated on the post-sale/maintenance phases. Keywords: Lifecycle Management, Quality Management System, Maintenance

2. Introduction on PLM concept To obtain better performances, enterprises need management systems that allow a greater synchronisation among all functions and activities of the value chain and able to manage, in an integrated way, the answers to the demands of the market (Subrahmanian et al., 2005). Some demands are quite difficult to achieve and may need many business requirements, such as:

     

Times and budget projects’ respect; Partners using to promote the innovation; Processes trace; Adherence to the business requisites; Increase the productivity of the workforce; Re-engineering of slow processes;

The PLM paradigm aims at giving an overall solution, using the product lifecycle as a general supporting framework (Stark, 2005). It considers the hole phases of the life of this product, from the first footsteps of an idea, crossing its development, launch and, finally, following the market phase, with a careful maintenance (where it is possible) to lengthen as much as possible its useful working life (Fontana, 2005; Elangovan et al., 2006). PLM identifies the necessary contents to the completion of each phase and the critical runs or the flow with the possible “bottle hills” or weak spots of the process (Pratt, 2005). It manages the “knowledge business” in the way to integrate persons, processes and technology, to facilitate the creation, management, distribution and use of all the product related information from its initial conception to the end of its life. The finalities of such PLM paradigm can be summarized as follows (Figure 1):

Product Lifecycle Management

Modular

Exhaustive

Demonstrable

Figure 1 – PLM paradigm specificities The modular structure makes us able to individuate fastly the possible re-usable components and each component of the system is described in terms of: Requisites, External interfaces, Architecture and documentation of development; and Requisites’ tests. The exhaustivity allows to cover all the necessary phases related to the realization of the product; allowing to individuate those that fit better to the particular application. The demonstrability offers the possibility to document the process during its lifecycle across the development of documentation on product, analytical validation of requisites, simulations, comparison with existing systems. The Lifecycle concepts (Garetti et al., 2005) related to some activities around the product are summarised as follows (figure 2). The QMSs, through their specific procedures and modules deal

with all these activities, assuring that they are accomplished according to the enterprise’s Policy of Quality and to the objective of level of service to guarantee to the customers: 1.

Market analysis, across the study of Customer Relationship Management of the specific market sector, analysis of the demands of the portfolio customers, evaluation of the new production capacity. 2. Planning of the business resources, with an Enterprise Resource Planning and definition of the strategies to adopt. 3. Planning analysis of the operational formalities and quality controls about their performances within all the phases of the project to guarantee that the products answer to the predefined requisites of quality and reliability. 4. Prototype definition; in which a golden item (prototype) is realised attesting the relative requisites. 5. Logistics, Delivering Analysis, times and methods. 6. Quality Analysis and improvement of the product in relationship with the quality policy of the enterprise. 7. Staff deliveries; definition of Staff’s operative responsibility and formality that influence the product’s quality. 8. Assembly and production, in which are accomplished each issue related to the production phase (e.g. analysis of the bill of materials, times and production methods production line characteristics, layout, etc.). 9. Tests and simulations, defining test campaigns and the related operative testing responsibilities and formalities, sales and distributions. 10. Assistance and maintenance, defining a strategy of sale and post-sales assistance, such as preventive maintenance, contracts of maintenance, manuals of selfmaintenance.

Assistance

Market analisys

Sales and distribution

Enterprise resource planning

Simulation and tests

Planning

Assembly and production

Prototype

Staff deliveries

Logistics

Figure 2 – Lifecycle and QMS

3. Product Lifecycle Management and Quality Management Systems As stated, the present paper addresses the issue of improving the development of a QMS according to the objectives linked to the lifecycle of a product. The main task is to embed the main lifecycle concepts while developing the QMSs (for example for an ISO 9000 Certification), facilitating the data sharing and determining an unique path that allows having a global vision on the whole life of the product (Bouras et al, 2005). Product Lifecycle Management is able to tie to Quality Systems for defining more in detail the managerial strategies to follow the product during its lifecycle (Fontana, 2005). Figure 3 shows the concept of Deming Quality Wheel, as the concept of quality is linkable to the lifecycle management, starting from the customer’s analysis requisites, going to the responsibilities of the direction and the continuous amelioration policy that determines the set in actions of the following known QMS statements (Foster, 2006):  

communicate to the organization the importance to comply with the customer requirements and to the legal ones; establishing the Quality Policy;

  

assuring that the objectives for the quality are defined and known; Making the reviewing of the system by the Top management; Assuring the availability of resources.

Assistance

Figure 3 – Quality Systems and Lifecycle Management

The objective is to assure that the realization of the product is done in accordance to the predefined qualitative standards. In this context, PLM techniques (hrough its central functions accomplished by systems such as Customer Relationship Management, Enterprise Resource

Planning and Product Data Management) give the key management strategies to follow analytically the life of the product (Pratt, 2005).

4. Integration of Lifecycle concepts into QMS The possibility of embedding Lifecycle concepts into a QMS has been structured trough the five phases of a QMS:     

Phase 1 – Product conception Phase 2 – Engineering Phase 3 – Assembling and/or production Phase 4 – Logistic Phase 5 – Assistance and maintenance

In the following paragraphs we will define in details the embedding issues and possible operative tools for the Assistance and Maintenance phase and then we will extend the approach to the other phases. The assistance and maintenance is a phase that may determine the extension of the maturity's period of a product in its lifecycle. During this phase it can be necessary to adopt policies of assistance/maintenance to guarantee to the consumer the possibility of a realiable utilisation of the product for the most part of its useful life (Baldini et al, 1999). Quality systems do not define specific approaches for the management of the post-sale assistance, but they leave to the organization the freedom to fix its own procedures. The lifecycle links to this phase an approach of Customer Satisfaction with a careful analysis of the product in terms of performances. As well known, the reliability of a product during the lifecycle can be represented through a curve (Figure 4) denominated bathtub curve (Carter, 1986) in which λ expresses the failure rate related to the three main life periods of the product (beginning, middle and end of life). λ(t) = Failure Rate

Childish breakdowns

Useful Life

Beginning of Life

Middle of Life

Breakdowns for wearing out

End of Life

Figure 4 – Bathtub curve To use a lifecycle approach, the enterprise has to individuate the three periods that characterize the product in the bathtub curve: Childish breakdowns, Useful life, and Breakdowns for wearing out. The childish breakdowns are referred to the period of adjustment (“Infantile mortality”), these faults are usually due to wrong design processes, production and/or defective components coming

t

from the suppliers. From a point of view of the customer's satisfaction, the infantile mortalities are unacceptable. Consequently, to avoid the premature mortalities, the supplier of the product has to determine the methods to eliminate the defects. The respect of design specifications, through a correct transmission of the information, is a way that a PLM system should suggest. In addition to better design methods, we need to anticipate the test phases in such a way to evaluate the design weaknesses and discover the specific problems related to both raw material and product components. In the figures 5(a) and 5(b) the two limit cases are depicted. In the first curve the optimal case is depicted because the rate of breakdown is the lowest possible and the useful life is lengthened. The second one, instead, shows a situation of very bad planning in which the useful life is nearly inexistent (Levitt, 2000). λ(t) λ(t)

t

t

Figure 5

(a) – Project optimal situation

(b) – Project bad situation

The objective of the PLM, in this phase, is to lengthen as much as possible the space of the useful product's life, keeping low the costs of maintenance. For PLM purposes the following maintenance policies can be adopted (Baldini et al., 1999): Failure maintenance: The maintenance action is performed in consequence of a damage or generally at the moment when happens a breakdown. Its advantages are low costs, if correctly applied, and the fact that it does not require organized structures and/or complex plannings. The disadvantages are that any breakdown can have safety problems and/or interruption of the working of the product. This type of maintenance does not allow the optimal use of maintenance teams, often left in waiting for the occurrence of breakdowns, and the spare parts waiting can be high. Preventive maintenance: Under this category are included all those interventions performed after a certain time period, defined by the working mean life of each component of the product. Among advantages, it allows a reduction of the breakdowns, a better use of the maintenance’s team, and an optimisation of the spare parts waiting times. As well know the adoption of this policyincreases maintenance costs. Furtherm it is correctly applicable only when the breakdown rate λ and its related function λ(t) are well known. Predictive maintenance: this type of maintenance is based on the concept that the most part of the breakdowns does not happen instantly but they are related to a certain signals and/or variables measurement in a certain time period. The possible types of measurements are the following  Vibrations measure;  Heater analysis;  Lubricating oil analysis;  Acoustic measures;

 Process parameters;  History of the maintenance of the product. After this first phase of surveys, it is possible to develop activities, of analysis and planning for the actions aimed to increase the useful life of every component, seeking the correct compromise between performances and effectiveness. The described maintenance activities can be linked to the λ(t) curve as shown in figure 6.

t The global cost of the failure maintenance is smaller than the global cost of the preventive maintenance

Failure

Failure

Failure

The global cost of the failure intervention is greater than the global cost of the preventive maintenance. The single cost of the inspection is greater of the difference between the global cost of the failure maintenance and the global cost of the preventive one.

Failure

Failure

Cyclical maintenance

The global cost of the failure maintenance is greater than the global cost of the preventive one. The cost of a single inspection is smaller than the difference between the global cost of the failure maintenance and of the global cost of the preventive one.

Condition Maintenance

Condition Maintenance

Condition Maintenance

Figure 6 – Linking of maintenance policies to the λ(t) curve

Regarding to the lifecycle point of view, the following main actions should be accomplished in the post-sale assistance phase:  Decrease as much as possible the “infantile mortality” time through efficient design methods, correct supplier selection and an exhaustive campaign of experiments on the prototypesDefine a plan of preventive maintenance through specific contracts of assistance with customers Define some methods of predictive maintenance that can discover the possibility of a fault and suggest the customer to call the assistance before the fault appears. This allows reducing the possibilities of faults and high expensive corrective maintenance actions during the useful life. The following table 1 shows the actions for the embedding of lifecycle concepts in the maintenance phase, while table 2 makes relationship between the QMS information and the improvements that can be obtained with the introduction of the lifecycle concepts. Table 1 – QMS needs and lifecycle actions for maintenance phase

Phase

QMS statement

Assistance and maintenance

The quality systems assess the maintenance phase as follows: “The organization has to define the activities for the release and the delivery of the product and for the assistance after sale”

Lifecycle actions

- Bathtub curve analysis. - Determination of the critical components of the product - Creation of contracts for planned maintenance - Definition of user and maintenance manuals more directed to the customer with a Frequently Asked Questions section

Operational tools for integration with the QMS Definition of a procedure that assesses the creation of specific contracts for preventive maintenance

Table 2 – QMS improvements with PLM concepts embedding in maintenance phase QMS Improvements with a PLM system

Phase

information Assistance and maintenance

Information on the activities performed by maintenance operator during the post assistance-sale

- Greater prevention to the breakdowns - More complete information on the lifecycle of the product after the sale - Possibility of planning of maintenance activities, with a better use of the maintenance's team and a better optimisation of the spares - Better costs determination from customer side: With a contract of maintenance the customer has the complete control costs during product utilization - Maximization and optimisation of the product's work time - Higher value in case of resale

This analysis has been extended to four other phases of the lifecycle and structured in table 3. Table 3 summarizes the relationships that can be set in QMS systems with respect to PLM point of view.

Table 3 – QMS improvements with lifecycle concepts embedding in other four phases of the product lifecycle Phase

Product conception

QMS statement

The organization has to define the requirements related to the customer’s perception and about how much the organization has satisfied the customer’s requirements.

Elements of entry: functional requisites and performances.

Design

Elements of exit: satisfaction of the input requirements with respect to the enterprise’s philosophy.

Definition of processes, documents and specific resources to realize the product Assembly and/or Production

Planning of each specific activity of verification, validation, monitoring, inspection for the product and the related acceptance criteria The organization has to assure that the supplied components fit to the specific supplying requisites.

Logistics The organization has to evaluate and select the suppliers on the base of their ability to supply product in conformity to the enterprises’ requirements

Lifecycle actions  Market analysis and results elaboration  Setting up a system for a better attention to the customer, across the creation of a "listening team" able to understand the real requirements of the consumer  Development of products, or parts of product in collaboration with the customer  Creation of personalized offers  Customer's segmentation

 Creation of a “Design Team” able to make control and audit in standardized manner.  Correlations with existing projects.  Realisation of a dossier for each product that contains information on: CAD ketches, BOM, materials list, production plan  Sharing design information through business tools (like internet).  Management of the production team to get the maximum output from the business knowledge  Definition of measurable and testable steps  Continuous exchange of information between production departments  Determination of the product's cost  Determination of production times  Buffer costing  Control of the products’ flows  Identification and scheduling of the processes and the produced components  Packaging analysis  Information on how to retrieve the product 's parts  Knowledge on transport's characteristics, related methodologies and delivery times

Operational tools of integration with the QMS Creation of a form/procedure for customer satisfaction (needs of the customer, possible suggestions to improve the product…) Extension of the procedure "resources management" by creating a new procedure that defines a listening group. Creation of a form for customers segmentation (information/data on the customers and their previous transactions)

Creation of a new form of design history that contains data on existing and previous projects, in order to be able to do correlations Module of Bill of Materials (BoM) that determines a detailed list of the product components

Definition of an additional procedure (to that one related to product realization) to determine costs and times of production

Definition of a procedure/form for the determination of:  warehouse costs  transportation flows  transport features that gives additional data related to the supply features

5. Case Study The possibility of embedding of lifecycle concepts into a QMS for the assistance and maintenance phase has been tested in an enterprise producing power generators. The enterprise is ISO9000 certified and produces 20 different models of power generators in 6 different plants. In our application case we have analysed a new mid-range model of power generator (fig 7). This model will substitute an old one which is the most known in terms of diffusion and utilisation, representing 15 % of the total sales of the enterprise

Figure 7 - The new product analysed for the case study The product is made by a steel sheet chassis with a four cylinder engine (figure 8) and the related generator unit. The entire unit is managed through an electronic panel.

Figure 8 – The steel chassis and the engine The enterprise had a failure-based maintenance system, oin which the maintenance action is activated on the calls of the customers. First, the mean useful life of the machine has been determined. This has been done after an experimental campaign, analysing a production lot of six machines during ten months. The Bill of Materials of the product has been organized into eight sub-products with respect to the possible maintenance activities as follows:   

Chassis Fuel tank Cabin

    

Engine Alternator Battery Electric panel Command centre

The first phase of the analysis is related to the break-in period related to 700 working hours, corresponding to three month. This first survey analysis has spotted out the main problems due to welding errors on the fuel tank, while the percentage related to engines breakdown is due to various factors, as the turbine, a defective battery charger, or failures related to the electric starter. During the measurement campaign the mean on the total breakdowns for the six machines observed has been calculated. The results of the breakdown rate (λ) are summarized in table 4. Table 4 – λ values for the first phase of life Sub-product λ (%) Chassis 0.3-0.5 Fuel tank 0÷0004 Cabin 0 Engine 0÷1 Alternator 1÷2 Battery 0.7÷1 Electric panel 0.1÷0.3 Command centre 0.5÷1 After the first phase the useful life of this kind of group is assessed from 700 up to 6000 non stop working hours (24 hours per day) which corresponds approximately to 10 months. These results of the breakdown rate (λ) for this phase is summarized in table 5. Table 5 – λ data for the phase of useful life Sub-product λ (%) Chassis 0.1÷0.2 Fuel tank 0 Cabin 0 Engine 0.3÷0.4 Alternator 0.1÷0.15 Battery 0.3÷0.5 Electric panel 0.02÷0.03 Command centre 0.2÷0.3 Finally, Table 6 shows the breakdown rate in the last phase of life of the product (> 6000 working hours), which is assessed approximately at two months, while in figure 9 we give the λ curve for one of the sub-products (Alternator). Table 6 – λ data for the last phase Sub-product λ (%) 0.7÷1 Chassis 0.5÷0.7 Fuel tank 0.4÷0.6 Cabin 0.7÷0.9 Engine

Alternator Battery Electric panel Command centre

0.3÷0.6 0.9÷1 0.04÷0.15 0.5÷0.6

λ

Childish

Useful life

Break-down

t

Figure 9 – λ curve for the Alternator Before the launch of the product on the market the procedure of the QMS has been revisited introducing two modules  A Technical Sheet, to report every maintenance activities made on the machine, the changed parts, the tests and controls made on the machines  A Planned maintenance sheet, related to the establishment of a maintenance contract sold with each machine. An extract of the module is reported in table 7: Table 7 – Planned maintenance sheet Working hours

Maintenance activities

100

700

2000

4000

1. Visual inspections; 2. Change of oil and filter of the engine; 3. Main belt control and regulation; 4. Cooling liquid control; 5.Battery control.

1. Visual inspection; 2. Oil change; 3. Filter change; 4. Cooling liquid refill; 5. Battery control; 6. Screws controlling; 7. Lock of control panel contact clips; 8. Alternator voltage control; 9.Tank cleaning.

1. Visual inspection; 2. Oil change; 3. Filter change; 4. Cooling belt change; 5. Cooling liquid refill; 6. Battery change ; 7. Engine valves tune up; 8.Fuel injectors control;

1. Oil change; 2. Filter change; 3. Cooling liquid refill; 4. Tune up Engine valves; 5. Fuel injectors control; 6. Tank cleaning 7. Screws controlling; 8. Lock of control panel contact clips; 9.Control of water pump.

To verify the results, we have compared the total working hours of the previous model and those of the present model after its launch on the market. With the technical sheet module we have taken the data related to the maintenance of five groups sold between October and December 2005 for 14 months. The results are given in the bar charts of figure 10, in which the data related to the total working hours of the previous model (right bar) are compared with the results of total working hours of the new model (left bar), obtaining an improvement up to 20%. 8000 7000 6000 5000

New Product Maintenence Old Product Maintenance

4000 3000 2000 1000 0

Figure 10 – Results related to the total working hours

Finally, we have taken the historical data of the previous model in terms of MTTR (Mean Time To Repair), MTBM (Mean Time between Maintenance) and MTBF (Mean Time between Failures), to compare with the data retrieved from the new one. The results are shown in Table 8 where we can se a huge decrease of MTTR and an increase of the MTBM

Table 8 – Value of maintenance times between the old and the new model

MTTR New model (preventive maintenance)

1.30 hours

MTBM

1700 hours

Old model (failure maintenance)

10-11 hours

MTBF

1500 hours

As last results we show the maintenance costs related to the previous and the new model, where we can see a great decrease of the cost (Table 9)

Table 9 – Maintenance costs between the old and the new models Cost of the single action

Yearly cost

New model

67.50 €

405.00 €

Old model

495.00 €

1485.00 €

6. Conclusion Product Lifecycle is going to be a key issue for product performances improvement both in terms of conformity to design specification and in terms of keeping these performance during the lifetime of the product. For the most parts of entreprises, especially SMEs, the Quality Certification as a performance key, has become a must for keeping them competitive in a global international context. In this scenario, the present paper has addressed the issue of linking the lifecycle concepts to the requirement of a Quality Management System (QMS) according to ISO 9000 norms. The main objective has been to face these concepts with the requirements related to a QMS, showing the possibilities of integration and related benefits. A general approach has been depicted and an application related to the maintenance area has been detailed. The results obtainend have led to the conclusion that a better diffusion of Lifecycle concepts imbedded into QMS statements can lead SMEs to a deployment of a Product Lifecycle Management (PLM) vision. This specific topic can be extended, giving the full managerial guidelines to apply PLM concepts with QMS requirements to the entire lifecycle of the product, towards a complete embedding of the two systems. A deeper analysis of this possibility could be a further development of this work.

7. References 1. K. Elangovan, V. Selladurai, S.R. Devadasa Maintenance quality policy statement: its research, design and executive support system Int. Journal of Technology, Policy and Management 2006 - Vol. 6, No.3 pp. 237 – 255 2. S. Thomas Foster On horizontal deployment of quality approaches within a firm - Int. Journal of Services and Operations Management 2006 - Vol. 2, No.2 pp. 168 – 177 3. Eswaran Subrahmanian, Sudarsan Rachuri, Steven J. Fenves, Sebti Foufou, Ram D. Sriram, Product lifecycle management support: a challenge in supporting product design and manufacturing in a networked economy, International Journal of Product Lifecycle Management, Vol. 1, No. 1, 2005 4. Abdelaziz Bouras, Sudarsan Rachuri, Balan Gurumoorthy, Alain Bernard, ISO 10303, The STEP standard for product data exchange, and its PLM capabilities, Internation Journal of Product Lifecycle Management, Vol. 1, No. 1, 2005

5. Marco Garetti, Sergio Terzi, Organisational change and knowledge management in PLM implementation, International Journal of Product Lifecycle Management, Vol. 1, No. 1, 2005 6. Riccardo Fontana, Opportunità e benefici dell’introduzione di un sistema PDM/PLM nelle PMI, plmentor.it, june 2005 7. John Stark, PLM: a new way of thinking about products, plmentor.it, june 2005 8. Marco Garetti, Sergio Terzi, Norma Bertacci, Maurizio Brianza, Organisational change and knowledge management in PLM implementation - Int. Journal of Product Lifecycle Management 2005 - Vol. 1, No.1 pp. 43 – 51 9. Dilani Jayawarna, Alan W. Pearson, Managing quality in the product development process: impact and implications through case study evidence - Int. Journal of Business Performance Management 2002 - Vol. 4, No.1 pp. 57-75 10. Eswaran Subrahmanian, Sudarsan Rachuri, Steven J. Fenves, Sebti Foufou, Ram D. Sriram Product lifecycle management support: a challenge in supporting product design and manufacturing in a networked economy, Int. Journal of Product Lifecycle Management 2005, Vol. 1, No 1 pp. 75-101 11. Michael J. Pratt ISO 10303, the STEP standard for product data exchange, and its PLM capabilities Int. Journal of Product Lifecycle Management, 2005 Vol. 1, No 1 pp. 86-99 12. Levitt, J., Complete Guide to Preventive and Predictive Maintenance, Industrial Press, 2000 13. Baldini, A., Furlanetto, L., Roversi, A., Turco F., Manuale di manutenzione degli impianti industriali e servizi, Ed. FrancoAngeli, 1999 14. Carter A.D.S,. Mechanical Reliability, Mac Millan, 1986