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With many of the world's governments committing to achieve net-zero greenhouse gas (GHG) emissions by mid-century, with well-defined milestones along the road, it is important to investigate how each sector can contribute towards achieving this global goal. The manufacturing sector, with its energy-intensive processes, large amounts of wastes, and hazardous and harmful emissions, is one of the main contributors to global GHG emissions, as well as other sustainability aspects, and, thus, it has great potential to contribute substantially to achieve net-zero objectives. This paper presents a techno-environmental-economic analysis of technologies that can play a key, enabling and leading role in the quest towards net-zero. Such technologies typically bring modest improvement in the environmental performance; however, the aim of this paper is to demonstrate how such small changes, when implemented in an industrial setting, can contribute significantly to the collective improvement in the environmental performance. In order to put the potential improvements into perspective, a real case study from the UK aerospace manufacturing sector is conducted. In the case study, metrics measuring potential improvements from the installation of a low-to-medium waste heat recovery system, and the upgrade of electric motors in the shopfloor to more energy efficient ones, are calculated through environmental and economic models. The models are then subject to a series of sensitivity analyses experiments to help understand the impact of different sources of uncertainty on the perceived GHG emissions, and economic and energy savings. The techno-environmental-economic analysis results revealed that these small changes, when implemented in an industrial setting, can indeed bring valuable improvements in the environmental performance of a manufacturing institute. Further, the sensitivity analysis experiments demonstrated how the environmental and economic performances are not adversely affected by different levels of fluctuations in key, likely to fluctuate, input parameters. [ABSTRACT FROM AUTHOR]

Friction stir welding (FSW) is a relatively new manufacturing process (invented in 1991 at the Welding Institute, UK) and more than 5000 scientific articles have been published in the past 10 years in indexed journals demonstrating the robustness of the research. However, further research is necessary to ensure safe use of the technique for structural components, particularly with reference to the aeronautics industry. Residual stresses and their consequences on the life of welded products must be fully understood, in addition to their correlations with other properties such as hardness, strength, and microstructure. This paper is a part of the research being conducted to evaluate the impact of four FSW techniques (bobbin, top-sided, bottom-sided, and double-sided) on the mechanical properties in dissimilar thick joints (12.7 mm) of aluminum alloys (AA7181-T7651 and AA7475-T7351) used in the aeronautics industry. The residual stresses were measured using the incremental blind hole technique and analyzed using the integral method. The longitudinal residual stresses were all positive, with values between 100 and 200 MPa in the stir zone, whereas the transverse ones were all negative, with values between 0 and − 100 MPa. It was possible to verify that the Bobbin process produced lower values of residual stresses and demonstrated better stability in its distribution compared to all the other FSW methods tested. [ABSTRACT FROM AUTHOR]

Metal castings are often questioned for their service life and reliability due to a lot of uncertainties associated with the process. It is important to virtually analyze these aspects of a cast product before it actually put into service. This paper presents a new approach to predict the fatigue life and reliability of ductile iron castings through coupled simulations and experiments. In this work, fatigue specimens are considered as sample cast products which are produced using an optimized mold design for minimum porosity. Radiographic examination is done to observe the quality of cast specimens. Experimental load-controlled fatigue testing of selected specimens is done and compared with simulated fatigue lives in fe-safe (Dassault Systems UK Limited 2015). Reliability of cast specimens under fatigue is computed using stress-strength model by considering the variability in both stress and strength. A safe load-induced stress is estimated to obtain infinite life of ductile iron parts under consideration. Furthermore, the reliability models are developed by fitting probability distributions to reliability estimates and determining the distribution parameters. It is concluded that the mold design optimization using casting simulations can lead to nearly defect free castings which can serve for the similar fatigue lives as their sound counterparts. Moreover, the probability of survival of the cast components for an infinite life can be computed using the classical stress-strength reliability model based on which safe loading conditions can be determined for almost any engineering application. [ABSTRACT FROM AUTHOR]

Establishing how to effectively manufacture cell therapies is an industry-level problem. Decentralised manufacturing is of increasing importance, and its challenges are recognised by healthcare regulators with deviations and comparability issues receiving specific attention from them. This paper is the first to report the deviations and other risks encountered when implementing the expansion of human pluripotent stem cells (hPSCs) in an automated three international site–decentralised manufacturing setting. An experimental demonstrator project expanded a human embryonal carcinoma cell line (2102Ep) at three development sites in France, Germany and the UK using the CompacT SelecT (Sartorius Stedim, Royston, UK) automated cell culture platform. Anticipated variations between sites spanned material input, features of the process itself and production system details including different quality management systems and personnel. Where possible, these were pre-addressed by implementing strategies including standardisation, cell bank mycoplasma testing and specific engineering and process improvements. However, despite such measures, unexpected deviations occurred between sites including software incompatibility and machine/process errors together with uncharacteristic contaminations. Many only became apparent during process proving or during the process run. Further, parameters including growth rate and viability discrepancies could only be determined post-run, preventing 'live' corrective measures. The work confirms the critical nature of approaches usually taken in Good Manufacturing Practice (GMP) manufacturing settings and especially emphasises the requirement for monitoring steps to be included within the production system. Real-time process monitoring coupled with carefully structured quality systems is essential for multiple site working including clarity of decision-making roles. Additionally, an over-reliance upon post-process visual microscopic comparisons has major limitations; it is difficult for non-experts to detect deleterious culture changes and such detection is slow. [ABSTRACT FROM AUTHOR]

This paper proposes a generic technique for the evaluation and comparison of the capability of manufacturing systems as a decision-making aid. It provides a methodical approach for extracting key capability factors (CF) and their degree of fulfilment by the institutes. The capability factors and their priorities are determined by experts in the related industry. By adopting this approach, a “ capability index” for each institute will be derived. This will be the basis for capability comparison. The proposed method applies fuzzy relations and analytic hierarchy process (AHP) techniques to calculate capability indices. The case study discussed in this paper is the result of a project commissioned by a prominent UK based company (UBC) to consolidate its EU operations. The results illustrate the effectiveness and flexibility of the proposed methodology for a wide range of applications. [ABSTRACT FROM AUTHOR]