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The purpose of this study is to develop a robotic training system for the hand movements during manual welding. The system provides real-time notice-feedback with sound or light alarms, whenever the welding hand vibrates beyond the nominal level observed with professional welders.

The large variations of hand movements are detected by monitoring the deviation of the tool position from a smooth curve estimated in real time by a Kalman filter. An alarm is generated in the form of a flashing light or beep sound whenever the deviations exceed a predetermined threshold. The performance of hand movements is measured in terms of the variations of the position data. Twelve novice and five professional welders took part in the experiments and answered a questionnaire that assessed the usability and work load of the system.

Compared to the sound alarms, the light alarms resulted in a larger and statistically significant decrease in the variation of hand movements of the novice welders and brought the level of variation close to that of the professional welders. The alarms did not result in a significant decrease in the variation of hand movements of the professional welders. The responses to the questionnaire indicated that both professional and novice welders found the system useful and they did not experience any significant work load.

The system developed in this study can ease the training of novice welders, by speeding up the learning and reducing the need for human tutors.

This study is first to provide real-time notice-feedback for training while manual welding, based on a comparison of the performances of novice and professional welders.

The purpose of the study is to analyse the feasibility of using the potential and exponential curve models to assess the learning of a group of welders, when welding stainless steel piping with the tungsten inert gas process.

The welding productivity data grouped according to the requirements of the ASME SECTION IX code is organised into two groups: average productivity and baseline productivity. When processing the adjustment to the two models, the Excel software Solver tool was used. The criteria for assessing the quality of the fit were: least squared method, Spearman's correlation coefficient and graphical method. The impact of the variation coefficient on the average productivity and the amplitude (difference between the minimum and maximum productivity) was also evaluated on the baseline productivity.

The curves elaborated based on the average productivity presented better quality of adjustment than those constructed from the baseline productivity. The potential and exponential models presented similar adjustment conditions, with the second having a slightly superior performance. There were no productivity gains due to learning in the studied time interval. The grouping of the average daily productivity data based on the diameter range established in the ASME code section IX presented satisfactory results, enabling its use by the industry.

There is no news of work on piping welding with this focus. The proposal to group the productivity data according to the degree of difficulty of execution established by the ASME code section IX, widely used in the industry, is a significant contribution to monitoring the evolution of learning. In the same way, the results allow to adopt the average productivity determined from the first 20 days of realisation of a project, as a reasonable indicator to estimate the future performance of the work, helping to correct deadlines during the realisation of a project.

The purpose of the study reported in the paper is to apply a structured problem-solving approach based on the Lean approach to analyse weld defects and derive appropriate solutions.

Manufacturing organisations involved in welding fabrication are expected to reduce weld defects to attain competitive advantage. Weld defects need to be systematically analysed for valve performance enhancement. In this research study, Lean approach is used to reduce variations and waste by annihilating the root causes for failures that occur during submerged arc welding (SAW) process.

The deployment of solutions facilitated weld defect reduction and substantial financial savings for the organisation.

The framework has been test-implemented for analysing variations and wastes generated in the SAW process. In future, studies could be conducted for assessing different welding processes.

The proposed Lean framework has been successfully implemented in a large-scale manufacturing unit involved in fabrication work.

Lean framework has been test-implemented in a large-scale manufacturing organisation involved in weld fabrication work.

The purpose of this paper is to present and implement an algorithm to prioritize welding quality deterioration factors for improving welding personnel performance. A case study is carried out in a piping components fabrication process which supplies these components to oil and gas production and processing facilities on the Norwegian continental shelf (NCS).

The quality deterioration factors' prioritization is carried out using statistical methods in conjunction with the data recorded in the welding inspection database (WIDB) of the case study company. Data cleaning and rearrangements were performed to reflect final objective. Based on the welding procedure specifications (WPSs) and quality imperfection groups classified in NS‐EN ISO 6520‐1, the analysis is performed to prioritize the welding quality deterioration factors.

Based on the WPSs and quality imperfection groups classified in NS‐EN ISO 6520‐1, it is possible to prioritize the welding quality deterioration factors. These factors are possible to use for improving the performance of welding personnel to assure the quality of welds in steel fabrications.

The factors prioritized are possible to use for improving the performance of welding personnel to assure the quality and reliability of welds in a steel fabrication.

Assuring quality as proposed in the manuscript, the catastrophic failures that are potential in production and process plants can be mitigated. This enhances health, safety and environmental performance of welds in steel fabrications.

The value of this paper is to illustrate an innovative approach to a real life quality problem; it demonstrates how the application of qualitative and quantitative quality instruments in accordance with technical specification can help in increasing and maintaining product compliance and in optimizing the management of resources.

The purpose of this paper is to identify, present and categorise the main requirements, challenges and impacts of Lean Six Sigma (LSS) applications. Emphasis is given to the soft impacts of LSS applications, which are intangible in nature and difficult to quantify and measure, highlighting the most frequently cited ones.

A qualitative synthesis of the studies using the narrative synthesis approach is adopted to descriptively summarise and categorise the requirements, challenges and impacts of LSS applications. The studies were searched by using the following keywords: “LSS applications,” “LSS requirements,” “LSS challenges” and “LSS impacts” in almost all major electronic databases such as Emerald, Taylor and Francis, ScienceDirect and Wiley. A total of 116 articles published between 2007 and 2017 in 41 academic journals were collected and reviewed. Consideration was also given to a number of substantial publications in 2006, 2018 and 2019.

In addition to its process efficiency and financial impacts, LSS was found to have another impact category related to individual and organisational behaviours. Management commitment, training and organisational culture were concluded to be amongst the most important and required categories for successful LSS applications. It was also found that the lack of awareness of LSS tools and benefits and the lack of change management and resistance to change were amongst the most cited categories of implementation challenges.

The studies published between 2007 and 2017 are mainly considered in this paper. It is believed that 10-year publication period considered in this research is sufficient to study the evolution, benefits, limitations and future trends of a particular research topic. However, the exclusion criteria used in the search process with respect to the articles’ year of publication and search terms and keywords may limit the generalisation of the research findings. In addition, the qualitative nature of this research study and the lack of empirical data to support its findings is another limitation that future research should consider.

This research paper may serve as a valuable source of information for LSS researchers as it will provide them with useful and new insights and directions for further research in LSS. It will also increase the awareness of LSS practitioners about the kind of impact LSS has, and therefore, achieve a better utilisation of its tools by ensuring availability of application requirements and overcoming application challenges.

This study differs from previous research studies as it focusses attention on the soft impacts of LSS applications and highlights them. The study identifies and prioritises LSS application impacts, requirements and challenges. The study on these aspects was found to be limited and lacking in previous research studies.

Learning as the way in which labor acquire new knowledge and skills has important strategic implications for the competitive advantage of an organization. The purpose of this paper is to present an agent-based modeling (ABM) approach to investigate the learning behavior of workers. The effect of interactions among different workers as well as the factors affecting the workers’ learning behavior is assessed using the proposed ABM approach.

For this purpose, the processes through which the competency value of worker is changed are understood and the workers’ learning behavior is modeled, taking account of various influencing factors such as knowledge flow, social ability to teach and forgetting factor.

The proposed model is implemented on a real steel structure project to evaluate its applicability and performance. The variation in the competency value of different workers involved in the project is simulated over time taking account of all the influencing factors using the proposed ABM approach.

In order to assess the effect of interactions among welders as well as the welders’ characteristics on their learning behavior, the competence value of different welders is evaluated.

This research presents an ABM approach to investigate the workers’ learning behavior. To evaluate the performance of the proposed ABM approach, it was implemented on a real steel structure project. The learning behavior of different welders (agents) was simulated taking account of their interactions as well as the factors affecting the welders’ learning behavior. The project involved the welding of a 240-ton steel structure. The initial project duration was estimated as 100 days. In this project, it has been planned to execute the welding process using three different welders namely welder A, B and C.

The main purpose of this paper is to identify sources of temp agency work satisfaction and discuss whether or not these sources differ from those well‐known to traditional satisfaction research (i.e. those appropriate for employees with a permanent contract).

The paper is a qualitative study (semi‐structured interviews and fieldwork) among low and medium skilled metalworkers (welders and fitters) in two Dutch companies. The authors were able to identify sources for temp agency work satisfaction: organizational conditions, central personality constructs, labour market experiences, and layoff experiences.

The findings in the paper conclude that satisfaction theory is transferable to temp agency workers, but that future satisfaction research should include less studied factors such as labour market and layoff experiences, as well.

The paper is a qualitative case study research within two Dutch companies and involved a certain occupational group: metalworkers. Consequently, the external transferability of the results (i.e. country, occupational group, industries) may be limited. Furthermore, the research approach used does not allow for the making of casual assumptions. For example, it was not possible to address the question as to whether “perceived alternatives” influences “sensation seeking” or vice versa. Longitudinal questionnaire research could help to clarify such issues. Job satisfaction theory in general is helpful in creating a framework for agency work satisfaction when it comes to Human Resource Management policies and practices. However, in order to explain agency workers' satisfaction, there is a need to broaden the traditional psychologically‐orientated theories and include aspects related to history and (occupational) sociology such as work experience in sectors where non‐permanent employment relationships are common.

The paper shows that hiring‐in companies can contribute to agency workers' satisfaction and, it is believed, other non‐permanent workers such as freelancers and collegial loan‐in, by means of equal treatment policies and practices with respect to job characteristics, development and mobility policies, working conditions, direct employee influence, and (fringe‐) benefits.

In this paper the focus has been on a relatively seldom‐discussed phenomenon in employee attitude research: temp agency work satisfaction. The authors focus on sources that can explain the preference for a ménage à trois employment relationship over life‐time employment arrangements with one employer, i.e. a traditional permanent labour contract between two parties.

This paper reports a study that compares two different team-building approaches. The first one is the traditional top-down management approach. The second one is a hybrid bottom-up approach based on the consensus model. The aim of this paper is to determine which of the two approaches is the most effective across a number of performance measurements.

A case study is presented using data collected and analysed from a small family-owned vehicle maintenance firm. A mixed methods approach to data collection is utilized, including participant observation, focus groups, survey questionnaires and organizational performance reports. A convenience sample of eight routine maintenance jobs was selected for team performance comparison purposes. The measures used for comparing the two team approaches were lead time, customer satisfaction ratings and employees’ satisfaction ratings.

The teams assembled using the consensus approach performed better than those selected using the traditional top-down approach across all three performance measures, i.e. the jobs were completed faster and both customers and employees were more satisfied.

This is an exploratory case study limited to one small family-owned business and, as such, findings may not be generalizable.

As an alternative to manager selected work teams, managers should involve and empower employees to select their own teams. This has the potential to offer benefits for both customers and employees of faster delivery times and increase satisfaction, as well as increase productivity for the firm.

This is the first field study to compare the performance of a hybrid, bottom-up approach to team building with the performance of a more traditional management, top-down approach to team building. It paves the way for a wider study to be conducted in the future to test the findings’ generalizability.

Large p.v.c. aprons, each measuring 120 × 30 ft. and weighing nearly half a ton, have recently been made for the Ministry of Supply for lining test areas where petrol tanks of up to 30,000 gallon capacity are subjected to impact and other tests. In use, the aprons are draped inside and over the sides of a sandbagged dispersal, and their purpose is to prevent the wastage of large quantities of petrol in the event of a tank bursting or splitting. The aprons were welded from Vybak VB.177 sheet of 0020 in. thickness by Plysu Products Ltd., Woburn Sands. This special grade of p.v.c. sheeting makes use of a polymeric plasticizer, and is thus resistant to the solvent action of petrol, which is liable to leach out conventional plasticizers. The aprons were made by welding sheets of Vybak together using an RF welder mounted on a wheeled chassis. Two operators were involved in the fabrication, one guiding the p.v.c. sheet, the other manipulating the RF welder. Vybak VB.177 p.v.c. sheet is supplied by Bakclite Ltd., 12–18 Grosvenor Gardens, S.W.1.

STIMULATING the interest of the employee in his job has become one of the most challenging problems facing management today. Daily repetition of tasks seemingly unrelated to the end product can very quickly cause boredom and fatigue, reducing individual efficiency and lowering productivity.