Failure Mode Avoidance in the Automotive Industry - Essay Example

FAILURE MODE AVOIDANCE IN THE AUTOMOTIVE INDUSTRY With the increasing competition it has become important for organisations in the automotive industry to manage technical risks. Using various tools, organisations can be able to identify possible modes of failure and to evaluate their effects and relevance. It is often argued that if all the companies were to embrace quality assurance right from the design stage, the incidences of failure would be minimized. This paper examines the role of various techniques in pushing the system away from the failure mode. In future, it is expected that proactive reliability tests will be embraced, in order to avoid simple defects. Such plans should target the development phase, where most of the failure modes occur. In addition, there is need to refine the techniques used in the project risk analysis as they are time consuming and require alot of resources. Table of Contents Table of Contents 3 1.Introduction 4 2.Background 4 3.History 5 4.Literature review 7 4.1 Operating window 9 4.2 Distance to failure mode 10 5.Techniques 11 5.1 FMEA 11 6.Case study 13 7.Challenges 14 8.Conclusion 15 1. Introduction In the recent past, the automotive industry has experienced an increase in competition. In order to provide customers with quality products and services, the manufacturing companies have been forced to adopt effective models. For instance, companies are being forced to re-design their product development process to identify and control the noise factor limits, and then come up with appropriate countermeasures. By distancing products from failure modes, companies can then be able to improve the reliability. The importance of using failure mode avoidance (FMA) methodologies is supported by many researchers. This paper examines the application of this concept within the automotive and manufacturing industries. 2. Background In the modern economy, it has become imperative to produce quality products that are appealing to the customers. With this in mind, car manufacturers constantly improve their production processes and their designs. The concept is very suitable in the face of growing recall cases, and a perfect example, can be borrowed from the Toyota Company. In 2013, the company recalled 1.3 million vehicles due to air bag defects and this exercise is expected to cost the company over $55 billion. In 2010, the company suffered a similar problem occasioned by the pedal entrapment malfunction. Since then, the company has conducted other recalls, and Ahsen, (2008) suggests that such incidences could have been avoided by implementing the Failure Mode and Effects Analysis programs. The FMA approach helps the manufacturers to identify high risk characteristics and develop appropriate measures to avoid potential failures. The current rules and regulations require the automotive industry to use multidisciplinary teams to identify failures and defects. The technical team is required to identify the following three types of failure modes: materials, processes and costs. The concept of the failure mode avoidance was first used by the National Aeronautics and Space Administration(NASA) group in 1960sand was later adopted by the Ford Motor Company in 1980s. Since then, the concept has been extended to the healthcare industry. In this sector, the concept is being employed to reduce the number of the medication errors, and evaluate the effects of the failure modes. The next sections examine the application of the concept in the automotive industry. 3. History The FMA concept was first developed by NASA, to improve and verify various software programs. The automotive industry adopted the technique in 1970s and the company to do was the Ford Corporation. The event follows the happenings which occurred in 1970s, in what is now referred to as the Ford Pinto case. The corporation failed to implement the necessary designs to avoid the high costs of carrying through with the process. The fuel tank was located behind the rear axle, making the Ford Pinto prone to rear-end collision. In one such case which occurred in 1978, three girls stopped on the road and shortly after, a truck drove into their car. The car burst into flames and led to loss of lives, which otherwise would not have occurred if the design was corrected in time. This story highlights the importance of identifying and correcting any design failures. Besides, being used extensively in the automotive industry, the concept has been adopted widely in the treatment of plants, plastics and healthcare industry, It is widely used for reliability analysis and removing the causes for failures or constructing effective systems that can mitigate the effects of failures. In the automotive industry the concept provides the manufacturers with details on how various systems relate and to identify any potential for failures. Besides, helping the manufacturers to understand the cause and defect relations, FMA concept helps them to create an appropriate framework for identifying mitigation actions and problematic areas. According to Graves (2000), the concept is widely applied in the designing of the built-in-Test and failure indications, drawing diagnostic flow charts, and improving the quality of control, inspection and manufacturing parameters. As indicated earlier, FMA is a key concept in the Failure Mode and Effects Analysis (FMEA) procedures. Once the failure modes are identified, the manufacturers then try to understand how they can affect the functions, items and the entire system. The next step is to examine each of the failure modes in terms of the worst potential consequence and identify failure detection methods. The third step is to come up with a corrective design in order control the risk posed by the failure mode. Finally, one should document and analyse the problems which were not corrected by the new design. In the automotive industry, one of the sources of failure modes is redesigning during the late stage of product development. Lack of enough time, limits the verification and testing process. Another source of the failure is lack of the interaction between the manufacturer and the suppliers. The traditional risk analysis model is as shown in figure 1. At times, re-designing requires the participation of the supplier, so that any technical issues arising can be addressed conclusively. Figure 1: Traditional risk analysis (adopted from: Nayab, 2013) 4. Literature review Reliability is an important in engineering and it entails two important factors: mistake avoidance and robustness. Mistakes refer to the design decision and manufacturing decisions that could lead to grave errors. Reliability can be achieved by reducing incidence of mistakes. On the other hand, robustness refers to the ability of a system to operate under a wide rage of conditions. It could also be defined as the probability of failure under specified operating conditions. Closely related to the concept to reliability is Failure mode avoidance entails expanding the failure mode boundaries in order to create a large region in which the system can function effectively. Franklin, Shebl and Barber (2012) observe that failure mode avoidance reduces the ‘specified operating conditions’. Franklin, Shebl and Barber (2012) classify the failure modes into two main groups: hard and soft failures. Hard failures are serious in nature, and they render a system dysfunctional. Hard failures also make it impossible for a product to serve its function. On the other hand, soft failures are classified as partially functional, degraded, intermittent or unintended. Partial failures affect the effectiveness of system performance while degraded failures are characterized by deviations. Systems with degraded functions need to be replaced for them to serve the intended purpose. The intermittent failures occur sporadically while unintended functions happen in the absence of appropriate operating conditions. Failure Mode Avoidance concept as suggested by Carbone and Tippett (2004) helps the company to avoid potential defects during the product development and testing stages. Some of the failure modes include mistakes and lack of rustiness. During the production process many mistakes could occur, but they can be avoided through careful planning and awareness. To improve the robustness and the reliability of the system, there are several strategies that can be used. Firstly, one could change the design to make it insensitive to the noise factors. Secondly, one could remove the noise factors or use a compensation tool. Finally, one could opt to shift the failure mode to another area where it will lead to lesser harm. Another common theme is the use of scientific methodologies to in the identification of the failure modes. The quantitative criticality analysis is used to estimate the loss resulting form each failure mode. According to Carbone and Tippett (2004), the criticality of each potential failure mode is obtained using the following components: item’s unreliability, mode ratio of unreliability and probability of loss. The quantitative analysis be could also be applied to estimate the number of the occurrences over a specific time interval. Some of the quantitative techniques that are used by the manufacturers include: the handbook reliability data, past experience, and Bayesian combinations. On the other hand, qualitative criticality analysis is used to evaluate risk and prioritize corrective actions. The qualitative approach to risk analysis involves: estimating the potential effects of failure, estimating the occurrence rate for each potential failure mode and establishing the severity of each failure mode through the use of criticality matrix. As suggested above, FMA involves deviation from the intended function and this deviation can be represented graphically. Some of the common approaches use to identify failure modes include: operating window and the distance to the failure mode. Each of these techniques is discussed below. 4.1 Operating window The concept was developed at the Xerox Corporation in 1970s and it is based on two practices: increasing the value of noise factors and changing the value of control factors (Pollock 2005). Xerox used the ‘opening window’ process to improve the reliability of the paper handling machines. Prior to embracing the concept, the failure rate was abnormally high and the quality of products was very low. The engineers in the company sought to reduce the high failure rate, by using more reliable machine configurations. In Pollock’s (2005) view, the concept borrows heavily from the Taguchi’s quality philosophy, where the quality of the products is measured according to the size of operating window. According to Pollock (2005), this metric is commonly used to measure and improve the system’s robustness and identify any weaknesses by employing large magnitudes of noise to the system. It could be described as a range where an item functions without failure and so the objective of a manufacturer it expand this component as much as possible. The concept of Operating window is shown on the graph below (Graph 1). In this graph, the failure mode, region is pushed away from the operating window. Graph 1: Adapted from Clausing (2004) 4.2 Distance to failure mode Puente, Pino, Priore and Fuente (2002) observe that this metric is quite similar to the Opening Window concept. This metric applies the following concepts: probability, dispersion, functional output and signal-to-noise ratio. The probabilistic approach seeks to push the system away from the failure mode. The dispersion concept likewise seeks to push the system from the failure modes. The relevance of the opening window concept is well evaluated by Clausing (2004). In this article, Clausng (2004) criticizes the use of traditional reliability engineering tools such as bathtub curves and mean time to failure. Once the system is exposed to large noise levels, failure modes can easily be detected. Noise is characterized as the variations in production, environment and as a result of time and use. The concept of operational window as suggested by Clausing (2004) is very prominent, and it will continue being used in the automotive industry. Clausing (2004) suggests that robustness can be improved by controlling the physics of the system. The application of this approach requires the user to go through a number of steps. Firstly, the user should select an appropriate noise variance, define the failure rate and then apply the stressing noise. The next step is to determine the range of the defining noise variable, after which the user then expands the operating window. Using this approach in the automotive industry offers the manufacturers a number of benefits. Firstly, this practice is very easy to implement in the automotive industry and it is inexpensive. Secondly, the process accommodates two or more failure modes and can be applied in a variety of systems. Finally, the concept provides the industry with great improvements. The engineers could also use the ‘slider bar’ approach to measure a system’s sensitivity to noise. 5. Techniques Related to the concept of the Failure Avoidance is the ‘physics of failure’ approach which was developed by the CALCE at the University of Maryland. The approach is now readily used in the process of product development and life testing. This science-based approach to reliability uses a mix of the modelling and simulation to reduce the decision risk. The approach is also extensively being used to understand the system performance and evaluate the causes of failure. In the automotive industry using the ‘physics of failure’ concept allows the manufacturer to identify failure mechanisms. Currently, the concept of the ‘physics of failure’ concept is not only being used to reduce incidences of failure, but also for computer modelling. The automotive industry has been experiencing major changes such as massive electrification and the need to shorten the development cycles. Using physics based models allows the engineers to try out new designs without building physical prototypes. Using advanced computer aided engineering methods; the manufacturers can also create simulations, which is less costly compared to developing and testing physical prototypes. As suggested the concept has a host of benefits including: providing the engineers with design-in reliability, increasing the fielded reliability, improving prognostics and decreasing operations and support cost. 5.1 FMEA One of the methods for failure reduction is FMEA and it aims to recognize and evaluate the potential failures during the production process. The concept applies the ‘bottom-to-top’ approach to determine how failure modes will affect the upper system levels. The concept is classified into the following components: system, design or construction, process, service and softwarethe different types of FMEA can be seen in Table 1. While the main function of the process is to minimise the likelihood of failures occurring, it also refines the process and product requirements. In this regard, discusses that this tool could be used to assess the customers’ details and identify design characteristics that could lead to failures. Table 1: FMEA types-usage In the recent past, the concept has been integrated with engineering processes. A number of standards have already been developed and they include: Automotive Industry Action Group, Society of Automotive Engineers and Verband der Automobilindustrie (VDA). The FMEA incorporates three processes: probability of failure occurrence, the severity of failure and the capacity to detect failure. The severity, occurrence and detectability guidelines that are used to design the FMEA are shown in Appendix A. Although the technique is readily used in the automotive industry, it has been criticized on various grounds. Firstly, using the RPN approach is not accurate and is not an effective measure of proposals for improvements. In addition, the concept is not realistic because it does not incorporate to changes ion project life cycle and budget. It is also quite common for the companies to delegate the corrective actions to the quality department. The challenges of using the FMEA concept are well captured in an article titled, the reduction of irregularities in the use of “process FMEA”. In this article, Estorilio and Posso (2010) point out that the approach is expensive and time-intensive. Many other researchers concur with these findings, and one such writer is Graves (2000) who argues that the development of the FMEA report takes a lot of time and effort. It is also quite often for the suppliers to delegate their duties to other smaller requirements, and in the process the quality requirements are not observed. In another article titled, cost-oriented failure mode and effects analysis, Ahsen (2008) discusses how the FMA may lead to wrong decisions. For instance, the tool does not take into consideration the potential interdependencies between various failure modes and effects. 6. Case study Trammell, Lorenzo and Davis (2004) examine the FMEA using the example of an international automotive organisation based in Brazil. According to Trammell, Lorenzo and Davis (2004), the product development process follows the framework developed by Cooper’s while gate decisions are carried out in accordance with the ‘delivery fulfilment list.’ In order to minimise failures during the production process, the company has adopted the structural design failure framework which has the following levels: vehicle level, systems level and subsystem level. In yet another study, the FMEA concept to improve the functionality of a cooling fan motor. Vehicles have an internal cooling system which provides the engines with appropriate working temperature while preventing breakdowns. The system has many components which include electro motor, liquid, radiator, water pump, and thermostat tubes. To improve the lifetime of the cooling fan from 500 to 3000 hours, a proper analysis is performed (Table 2). The electro-fans are also redesigned and experimental testings are also done. Table 1: Adopted from Shebl, Franklin and Barber (2009) 7. Challenges Clausing (2004) suggests that it is very hard to implement the FMA concept most of the times due to several factors. Clausing (2004) further suggests that failure modes ought to be identified at the stage which they were created and then fixed at once. Most importantly, the failure identification process should be supported by appropriate tools. However, such a process is likely to be faced with a lot of challenges. For instance, failure modes are hard to identify, especially in the complex multi-disciplinary systems. Another major challenge is the lack of enough resources. In the current economic times, automotive manufacturers are striving to reduce the cost of production. Keeping the costs as low as possible is very pivotal, because producing expensive vehicles will end up being counterproductive. Under such conditions, it becomes hard for the company to conduct all quality-related assessments. At the same time, the failure mode avoidance requires vast financial resources for successful implementation. A lot tests need to be carried out and corrective measures need to be initiated. While FMEA is suitable in detecting and correcting failures, there is another common technique which is almost similar. The FMECA (Failure Mode, Effects and Criticality Analysis) is very often used in the automotive industry, and is an important tool when conducting the reliability tests. Its methodology is based on the inductive approach, and it could be quite costly to implement. FMECA helps the organisations to settle for the most effective and safest design. In addition, it helps the organisation to identify the single failure points, hence allowing the engineers to correct the anomaly before the actual production begins. Other interventions that could be adopted include fault tree analysis and deductive analysis. 8. Conclusion Failure terminates the ability of an item to perform its intended function and in the automotive industries it could to lead loss of lives. To address this problem, the car manufacturers have adopted standards to enhance the production of quality goods and to undertake corrective actions. By developing an effective system, failures can easily be detected in the areas where they are generated. However, it seems that in the automotive industry, there is also need to integrate the client’s system with the supplier’s chain in order to ensure raw material delivered are of high quality. Most importantly, some the FMEA processes should be refined to address some of the concerns raised by the researchers. If such an approach is taken, corporations will be able to observe the safety of the drivers, while minimizing the cost of undertaking correction actions. Potential failure modes could also be avoided by using the various tools suggested by many researchers. Reference list Ahsen, A. (2008) ‘Cost-oriented failure mode and effects analyses’. International Journal quality and reliability management 25(5), 466-476 Carbone, T.A. and Tippett, D.D. (2004) ‘Project risk management using the project risk’. FMEA. Engineering Management Journal 16(4), 28-35. Clausing, D. (2004) ‘Operating window: an engineering measure for robustness/response’. Technometrics 46, 1 Estorilio, C. and Posso, R. (2010) ‘The reduction of irregularities in the use of “process FMEA’. International Quality and reliability Management 27(6), 721-733 Franklin, B, D., Shebl, N.A. and Barber, N. (2012) ‘Failure mode and effects analysis: too little for too much? BMJ Qual Saf 21, 607–611 Graves, R. (2000) ‘Qualitative risk assessment’. PM Network 14(10), 61-6. Pollock, S. (2005) ‘Create a simple framework to validate FMEA performance. ASQ Six Sigma Forum Magazine 4(4), pp. 27-34. Puente, J., Pino, R., Priore, P. and Fuente, D. (2002) ‘A decision support system for applying failure mode and effects analysis’. The International Journal of Quality & Reliability Management 19(1), 137-50. Shebl N.A., Franklin, B.D., and Barber, N. (2009) ‘Is failure mode and effect analysis reliable’. J Patient Saf 5, 86–94 Trammell, S.R., Lorenzo, D.K. and Davis, B.J. (2004) ‘Integrated hazard analysis: using the strengths of multiple methods to maximize the effectiveness’. Professional Safety 49(5), 29-37 Nayab N. (2013). Risk analysis v.s. FMEA. http://www.brighthubpm.com/risk-management/71098-risk-analysis-vs-fmea/ APPENDIX A 1. Severity guidelines for design FMEA 2. Occurence guidelines for the design FMEA 3. Detectability guidelines for design FMEA Read More