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Failures represent an important source of variability in service operations and a major performance challenge. As a consequence, the effective management of failures is a prerequisite to achieve lean services. The purpose of this paper is to focus on the operational perspective of failures; that is attempt to quantify the impact of critical failure parameters on key system performance measures, such as cycle time and work‐in‐process. The authors also analyze various operational concepts, or management practices, that service organizations use to address the effects of failures.

Discrete event simulation was used to model the behavior of a typical two‐stage service system (front‐office, back‐office), and design of experiments to estimate the impact of significant parameters that characterize service failures, on key system performance measures. In a final experiment, three of the most common practices used by management to address failures, and the impact of these practices on system performance under different conditions were analyzed. The findings are validated through a case study in the financial services.

The results of this study suggest that failures and rework degrade the performance of service systems. This adverse impact is reinforced, if specific inputs of the system deteriorate, such as the ability of the service organization to deliver appropriate quality, to detect failures early and to be capable enough to recover timely and efficiently from failures. In addition, the results show that typical management practices used to address the impact of failures have strengths and weaknesses depending on the characteristics of both the service system and the failures. If this is not taken into consideration, the above managerial practices may lead only to short‐term improvements, while the main causes of failures will remain unsolved.

Analyzing the impact of failures in a service environment is a challenging task. This paper complements the existing literature on service failures by focusing on the related effects on operations. With the use of simulation, the authors quantify the impact of failures on key aspects of operations of the service system and also provide useful insight into the parameters that determine the effectiveness of various management practices used in practice to address failures. Finally, the authors use a case study in financial services to validate the results.

This paper aims to consider a multi-site production planning problem with failure in rework and breakdown subject to demand uncertainty.

In this new mathematical model, at first, a feasible range for production time is found, and then the model is rewritten considering the demand uncertainty and robust optimization techniques. Here, three evolutionary methods are presented: robust particle swarm optimization, robust genetic algorithm (RGA) and robust simulated annealing with the ability of handling uncertainties. Firstly, the proposed mathematical model is validated by solving a problem in the LINGO environment. Afterwards, to compare and find the efficiency of the proposed evolutionary methods, some large-size test problems are solved.

The results show that the proposed models can prepare a promising approach to fulfill an efficient production planning in multi-site production planning. Results obtained by comparing the three proposed algorithms demonstrate that the presented RGA has better and more efficient solutions.

Considering the robust optimization approach to production system with failure in rework and breakdown under uncertainty.

Service businesses are struggling with customer demands for better quality service and managerial demands for cost reduction. There is evidence to suggest that service businesses are in practice failing on both these counts, seeing increased costs and reductions in service quality. The application of lean production approaches to the service context has been suggested as a means to resolve these problems, reducing costs and improving quality. Despite the validation of lean approaches in the product‐service context, the application of lean approaches in the pure service environment remains largely untested. The purpose of this paper is to assess the suitability of lean production methodologies in the pure service context.

Three financial service companies in the UK were followed through a common programme of lean transformation. The improvements observed in each company were recorded. The change programme is evaluated to determine the “leanness” of the initiatives. The suitability of lean for the service context is discussed.

The paper's findings highlight significant improvements in quality and cost positions with minimal investment through adoption of lean tools in the pure service context. The paper proposes the suitability of basic lean methodologies such as value understanding, process mapping and problem solving for the pure service context.

The lean approach is well established in the manufacturing sector and certain product‐service contexts. Evidence on lean in pure service environments is very limited. The paper addresses this shortcoming.

The general objective of this research was to identify the practices of the mass production industries, on the decisions related to the detection of defective products and to identify relevant criteria, actions, effects and variables to be used in a decision-making model.

A survey questionnaire was developed and structured in 20 questions, with 18 closed questions and 2 open questions. The questions were constructed based on the literature review, with the identification of 15 theoretical and practical concepts of quality. Seven other information requests were included, concerning the initial characterization of the defective items and industry. The company, the product, the processes and the defects were contextualized, and then the decision-making process was framed, to understand the factors that influenced it.

The industries of the Industrial Pole of Manaus discard or rework their defective products influenced by promoting the lowest cost and the required quality. The factors with the biggest influence on decisions are rework and disposal costs, and time available for rework and replacement. The main requirements defined for the decision-making model were: 1) compare the rework and discard options, only if the rework reaches the required quality level; and 2) identify and account the effects of defective items on quality, productivity and costs.

Overall, 109 questionnaires were sent, representing 21.3% (109/512) of the companies at the Industrial Pole of Manaus. The respondents represent 14.6% (75/512) of the population.

Defects can occur, requiring a decision that promotes the lowest cost and the required quality. Quality cost models do not show a systematic analysis for identification, accounting, evaluation of effects and criteria associated with the destination of manufactured defective items. Therefore this research was done to fill this gap.

The purpose of this paper is to investigate effects of the multiple rework of ball grid array (BGA) components on mechanical strength of BGA balls, as well as any possible intermetallic (IMC) embrittlement, and obtain data correlated with possible estimation on the maximum permitted limits of BGA rework.

In this paper, mechanical strength of BGA components assemblies with multiple numbers of rework operations was evaluated. Mechanical evaluation was conducted using BGA ball shear tests and four‐point bending tests of BGA assemblies. Test samples were prepared under the following conditions: virgin, one, two, three and five BGA reworks. Failure mechanism was evaluated using cross‐section and SEM analysis.

The results show that both ball shearing tests and four‐point bending tests indicates that strength of BGA solder ball itself was not reduced significantly after repair/rework operation from one to five cycles. The IMC structure layer after rework is a mixture of IMC, Sn‐rich and Pb‐rich phases. This mixture layers with thickness even more than 10 μm in thickness does not show reduction of strength of BGA solder balls and do not cause premature embrittlement. However, the bonding strength of the copper pads to the laminates is reduced with rework/repair operation, with the great reduction coming from the first and second rework operation.

In general, the industry recommends two rework cycles for BGA components on the same spot. This study indicates that further rework (up to five) causes little degradation, therefore there is room to increase the total rework cycle limit beyond recommended two for plastic BGA components.

Presented test results shows that in most cases industry overestimates risks associated with increased embritlement of the BGA solder joints due to the intermetallics growth after multiple BGA rework operations. Strength reduction of BGA assemblies is mostly associated with reduction of bonding strength of the copper pads to the laminates is reduced with rework/repair operation and number of reworks could be increased in most cases.

This paper proposes a decision support model that can be used to help decide the destination of defective products, for mass production industries. The objective of this model is to reduce the cost of the defect, and consequently reduce the total quality costs.

The decision model was developed based on the theory of quality costs and decision-making models, considering the practical aspects of reality through data collection, observation and experience in Industrial Pole of Manaus (Brazil) industries. A decision model adjusted to reality assists in the construction of the decision process, indicating the facts, data collection and the planning of the actions to choose the best alternative.

The specific contributions of this research are: (1) define a sequential structure of actions, effects and costs associated with defective items; (2) allow a comprehensive approach to failure costs, including various elements of lost opportunity costs; (3) minimize failure costs, and consequently reduce total quality costs, without necessarily investing in prevention and assessment; (4) describe the use and application of the built theory; (5) identify the quality cost elements most representative in existence of defective items; and (6) identify improvement points in the management of possible future defective items.

Much of the work of implementation of quality cost models do not emphasize the analysis of the destination of defective items. Also, there are no studies that use decision models with identification, accounting and evaluation of effects and criteria of quality, productivity and cost to define the destination of manufacture defective items.

In the assembly process of high reliability printed wiring boards (PWBs), rework cycles seem to be an unfortunate fact of life. The question repeatedly arises as to how many times a solder joint incorporating plated‐through‐holes (PTHs) can be reworked without degrading the configuration. By performing a controlled experiment, the authors were able to answer that question and make recommendations as to the limits that should be placed on the number of reworks. They were further able to look at the following factors: operators, board type, number of layers and solder temperature to determine which were the most significant in determining limits to the number of rework cycles. The results showed that the more layers the board contained, the more at risk the PTH was to rework‐induced defects. This perhaps defies conventional wisdom that the board type or temperatures were the driving contributors. The increased number of board layers corresponds to thinner dielectric layers. The experimental results were repeated in a theoretical review using a finite element analysis (FEA) model that was developed showing the thermally induced stresses in the solder joint and PTH region. For multilayer boards, it is recommended that rework be limited to three cycles. The present work shows that there is evidence of degradation by the fifth cycle on boards with thinner dielectric (10‐layer board, dielectric thickness 0.008 in.). By limiting the number of reworks, the risk of inducing failure mechanisms into PWAs (printed wiring assemblies) is dramatically reduced.

The purpose of this paper is to identify the main reworks and their causes in a case study of the ongoing mass housing project in Iran. Using the real data captured from the project, the most important causes for reworks have been computed and prioritized.

More than 900 non-conformance forms filled in the construction site have been used to categorize reworks. Then, the frequency and cost of each rework group in the project have been estimated. Finally, using these data, the primary classification and sorting of the main causes of reworks have been specified.

Results show “Poor site supervision and inspection” with 24 percent of costs had the most impact and “unclear project management process” with about 6 percent of costs had the least impact on the formation of non-conformances. “Cost of each incidence” (COI) ranged from 0.67 for “The need to categorize the complicated operations” to 1.86 for “Unclear project management process.”

The causes of rework which are not in contractor’s hand (like change orders from the client) have not been considered in this study.

Although some works have been done in rework causes, the key elements and causes of reworks in mass housing projects in developing countries have not been yet fully specified through the real data. Knowing the root causes of reworks can help project managers to remove them and reduce reworks costs in future projects. COI which is defined here for the first time and computed in a relative concept could be a good criterion to compare rework causes between two or more similar projects.

To share the findings of recent investigations of the influences of RoHS requirements on printed wire board (PWB) reliability.

Interconnect stress testing was used to measure the reduction in reliability of coupons that replicated high‐density multilayer circuit boards, after exposure to a simulation of the thermal excursion associated with “tin‐lead” and “lead‐free” assembly and rework. Coupons were preconditioned by exposure to tin‐lead assembly temperatures (230°C) or lead‐free assembly temperatures (245 or 260°C). Standard statistical methods were applied to the test data, which was compared between more than 20 dielectric materials.

There is a shift from copper quality being the dominant influence in reliability to copper and material quality working in concert being the major influence on PWB reliability. Delamination and crazing increases with lead‐free assembly and rework and this has the effect of artificially extending cycles to failure, frequently confounding data. Reliability testing to lead‐free temperatures requires an evaluation for delamination to ensure the cycle data are not artificially extended. A robust, well fabricated coupon's reliability is found to be reduced by 50 percent after lead‐free assembly and rework.

There is objective evidence of a significant reduction in reliability with the thermal excursion associated with lead‐free assembly but there has been no apparent reduction in acceptance criteria or limitation on warranties. This paper does not address the influence of reliability on the solder joints, components or other structures of an assembled PWB. This paper is limited to reliability influences on the PWB. The identification of materials used in this study is protected under non‐disclosure agreements.

This study expands the understanding of the implications of the effect of RoHS requirements on PWB reliability. It allows companies to optimise PWB reliability with quality fabrication, using robust materials and optimised PWB designs and to make sound business decisions in order to meet the new challenges of RoHS. Meeting the challenge of RoHS is not limited to a question of compliance by getting the lead out; it is also a question of optimising PWB's reliability.

The purpose of this paper is to improve the failure analysis and troubleshooting process in engineering to order (ETO) product development, and reduce the amount of parts with failures. This is important because parts with failures are associated with the additional costs resulting from corrections of the product, reduced productivity due to the time waiting for the corrected part, delays in delivery and harm to the image of the organization.

FMEA and A3 are combined in a document for failure analysis and recording of the generated knowledge. The method is applied to an industrial automation company that designs and manufactures ETO products. Initially, the failures identified in mechanical assembly products are mapped, and then FMEA and A3 are combined in a document template, and a checklist for reviewing the detailing is built. Then, the method is applied in the design phase, and also for solving conceptual failures in the mechanical assembly and testing phase and the knowledge generated is recorded.

The results show the feasibility of the proposed method for both failure analysis and knowledge generation. Moreover, the adoption of improvement practices in routine activities, for example, the checklist for reviewing the detailing, can reduce up to 10 percent the amount of parts with failures.

The integration of FMEA and A3 encourages group thinking and monitoring the implemented actions. Since the document contains minor changes in the layout from the design phase to the assembly and testing phase, it contributed to the understanding of the people who participated in performing each phase. It should be ensured that the participation of experienced individuals with a proactive assertiveness who encourage the exchange of knowledge, preventing recurring failures from occurring in the conceptual phase. The approach to ensure quality was well accepted by the personnel in the company, but the implementation requires changing habits and establishing new practices.

The method proposed in this paper was applied to a company that designs and manufactures ETO industrial automation products. Since such products have high variety, the company has different characteristics compared with the companies that were considered in the few publications that attempted to combine the FMEA and A3 methods for failure analysis. The proposed method provides convenience for queries and updates, since it allows the inclusion of different failures in a single A3 report, reducing the number of separate documents. Also, the method includes a checklist for detailing review, which contributed to the reduction of failures.