Proceedings of the Institution of Mechanical Engineers,Part B: Journal of Engineering Manufacture

This article presents a methodology that provides a continuous assessment of predictive maintenance (PdM) technologies with respect to specific business scenarios. The methodology integrates existing reliability and maintenance business analysis techniques and standards. The positive impacts that may have implementing these technologies have always been in mind. A critical simulation step is also added where different predictive maintenance strategies are simulated in order to obtain the optimal maintenance strategy. This Monte Carlo simulation relies on the reliability information based on the probability density distribution of failure for the system or component, providing as a result the optimal strategy among the proposed options. The article finally explains how this methodology has a positive impact not only on the cost-effectiveness of maintenance processes, but also on the maintenance information available.

Technology-centric products often contain parts, software, and materials that have procurement lives that end before the product they are in reaches the end of its life cycle. Life-cycle mismatches between parts and products, which is referred to as obsolescence, can result in large life-cycle costs for mission, safety, and infrastructure critical products, such as aircraft, medical, and military systems. Diminishing Manufacturing Sources and Materials Shortages is a type of obsolescence that describes the loss of the ability to purchase (or procure) a part (or its associated technology) from its original manufacturer. A key enabler for performing pro-active and strategic management of the life cycle of mission, safety, and infrastructure critical products is the ability to forecast when technologies and parts will become unavailable for purchase, that is, obsolete. This article reviews methods that are used to forecast obsolescence, focusing on long-term forecasting used to predict the obsolescence dates for technologies and electronic parts.

Waste Electrical and Electronic Equipment is one of the major waste streams in terms of quantity and toxicity, and a critical step in Waste Electrical and Electronic Equipment end-of-life processing is through disassembly. Compared with full disassembly, which is a sub-optimal solution due to its high operational cost, selective disassembly is more economic and practical as only selected parts with recycling potential are considered. In this article, a systematic selective disassembly approach for handling Waste Electrical and Electronic Equipment with a maximum disassembly profit in accordance to the Waste Electrical and Electronic Equipment and Restriction of Hazardous Substances Directives has been developed. First, a space interference matrix is generated based on the interference relationship between individual components in the three-dimensional computer-aided design model of Waste Electrical and Electronic Equipment. A matrix analysis algorithm is then applied to obtain all the feasible disassembly sequences through the obtained space interference matrix in a three-dimensional environment. Second, an evaluation and decision-making method is developed to find out an optimal selective disassembly sequence from the obtained feasible disassembly sequences. The evaluation takes into account the disassembly profit and requirements of the Waste Electrical and Electronic Equipment and Restriction of Hazardous Substances Directives, which regulate on recycling rates of different types of products and removal requirements of (1) hazardous, (2) heavy and (3) high-value components. Thus, an optimal solution is a selective disassembly sequence that can achieve the maximum disassembly profit, while complying with the Waste Electrical and Electronic Equipment and Restriction of Hazardous Substances restrictions based on a brute-force search method. Finally, an industrial case on Changhong liquid crystal display televisions of the type LC24F4 is used to demonstrate the effectiveness of the developed approach.

Electronic systems are prone to failures, whether during manufacture or throughout their in-service lifetime. A number of design and fabrication techniques are presently employed that maintain an economical production yield. However, the cost of through-life maintenance and fault mitigation operations for complex, high-value systems remains a major challenge and requires new design methods in order to increase their resilience. In this article, the focus is on applications that are sensitive to transient random errors caused by single-event upsets and multiple-bit upsets occurring within their electronic systems and sub-systems, as well as applications that benefit from fault detection and localisation. A novel self-restoration strategy is proposed based on a two-layer design approach comprising a fault-tolerant coordination layer with convergent cellular automata and a configurable functional logic layer. This design strategy is able to self-reconstruct the correct functional logic configuration in the event of transient faults without external intervention. The necessary convergent cellular automata rule set and state table sizes for 3 × 3 and 4 × 4 binary coded patterns are analysed in order to estimate the generic resource requirements for larger designs. Additionally, the possibility of exploiting the design for built-in fault detection and diagnostic reporting is investigated.

Despite significant advances in modelling and design, mechanical systems almost inevitably fail at some point during their operative life. This can be due to a pre-existing design flaw, which is usually overcome in a revision, or more commonly due to some unexpected damage during operation. To overcome a failure during operation, a new method in designing machines or systems is proposed that creates a result, that is, resilient to both expected and unexpected failure. By shifting the focus from a detailed assessment of the underlying cause of failure to how that failure will manifest, a system becomes inherently resilient against a wide range of failure modes. The proposed process involves five steps: cause, detection, diagnosis, confirmation and correction. This is demonstrated with an application to a generic 4 bar linkage mechanism. Through this process, the system is able to return to a near perfect state even after a permanent deformation occurs in the mechanism. These results show the potential that this self-repairing design process has applications including robotics, manufacturing and other systems.

The development of various nontraditional principles to finish the internal surfaces and passages is reviewed. In particular, attention is focused on three relatively mature finishing techniques: abrasive flow machining, internal magnetic abrasive finishing and fluidized bed machining. Their working principles, capabilities and limitations are evaluated accordingly. Finally, the significance of developing internal surface finishing capabilities and the vast potential ahead of this research field are highlighted.

Fluid jet polishing is an emerging process which possesses the advantages of localized force and less heat generation, as well as the stable and controllable material removal function without tool wear. Due to the complex machining mechanism, it is still difficult to model the material removal rate and predict the surface generation for fluid jet polishing. In this article, theoretical and experimental investigation of three-dimensional-structured surface generation by fluid jet polishing has been carried out. A surface topography simulation model is established for predicting the three-dimensional-structured surface generation by fluid jet polishing. A series of polishing experiments have been conducted to optimize the process parameters of fluid jet polishing and the fabrication of three-dimensional-structured surfaces. In terms of the pattern of three-dimensional-structured surfaces generated, the simulation results are found to agree with the experimental results.

Self-excited vibrations of the face milling process can result in instability, poor surface finish and machine tool failure. In order to avoid chatter vibrations, this article develops an algorithm for predicting the stability lobes for face milling processes. It considers the factors including radial instantaneous chip thickness, entry and exit angles and the dynamic interaction between cutting tool and workpiece which is often neglected by many researchers. An electronic impact hammer is used to identify the dynamic parameters of the face milling system. Milling experiments have been conducted to validate the predictive capability of the developed algorithm for stability lobes. The results show that the prediction model can estimate the stable and unstable zones for face milling process. This article provides a frequency-domain method for establishing stability lobes which can predict stability zones rapidly. The outcome of this research will bring about methodologies for cost-effective monitoring of face milling processes and maximize the material removal rate.

Carbon fiber–reinforced plastics have been widely applied in aerospace industry as aircraft structural components due to their excellent mechanical and physical properties. The countersinking process of the carbon fiber–reinforced plastic hole is indispensable for the assembly of countersunk head screw. In conventional countersinking process of carbon fiber–reinforced plastics, it is prone to produce the delamination, fiber pullout, poor surface levelness and dimensional accuracy of countersunk hole. As a new technology, the rotary ultrasonic elliptical machining for countersinking of carbon fiber–reinforced plastics is employed, which is a non-traditional process that can effectively improve the surface levelness, surface integrity and machining accuracy of carbon fiber–reinforced plastic countersunk hole. This article reported a feasibility study on the rotary ultrasonic elliptical machining for countersinking of carbon fiber–reinforced plastics without coolant for the first time. The processing principle of rotary ultrasonic elliptical machining for countersinking was illustrated according to the countersinking models and the equations of motion locus. Based on the principle analysis, the surface levelness, tool blades’ path and countersunk hole surface morphology in rotary ultrasonic elliptical machining of the separated and unseparated types were analyzed compared to that in conventional countersinking. In addition, the rotary ultrasonic elliptical vibration transducer was designed and fabricated, as well as the experimental platform was set up. The experimental results demonstrated that the rotary ultrasonic elliptical machining achieved much better results than that in conventional countersinking, such as lower thrust force, torque, cutting temperature, better surface levelness, hole dimensional accuracy, surface integrity and chip-removal effect. The experimental results also verified the feasibility of rotary ultrasonic elliptical machining for countersinking of carbon fiber–reinforced plastics.

This article proposes the sine series representation of jerk profile for acceleration/deceleration feedrate scheduling of parametric interpolator used in computer numerical control machining tools. By selecting the geometric sequence as the coefficients of the sine series, the closed-form expressions of the feedrate, acceleration and jerk profiles are obtained. The resulting feedrate profile is more concise compared with the polynomial profile and more efficient compared with the trigonometric profile. It can be well accepted by the conventional acceleration/deceleration feedrate scheduling algorithms. Also, an approach is proposed to determine the optimal geometric sequence that makes the tracking time as small as possible. Simulations and experiments of tracking complex contours expressed as free-form non-uniform rational B-spline curves are conducted. The results demonstrate the effectiveness of the proposed feedrate profile and the resulting feedrate scheduling strategy.

Most recent studies on machining parameter optimization in machining operations focused on reducing machining cost and energy consumption. However, environmental impacts caused by manufacturing activities were not involved in those studies, which can be quantified by equivalent carbon dioxide emissions. In this study, a direct method was proposed to quantify the carbon emissions generated during multi-pass turning operations. Moreover, machining parameter optimization models of multi-pass turning operations in dry and wet cut environments were established using an experimental design method. Three objectives were considered in both models: carbon emissions, operation time, and machining cost. Furthermore, a multi-objective teaching–learning-based optimization algorithm was used to deal with the models. The optimization results indicated that the use of cutting fluids could significantly reduce carbon emissions and machining cost and improve production efficiency in multi-pass turning operations.

In aerospace industry, the materials constituting aircraft evolved considerably in recent decades. The choice of composite materials (carbon fiber–reinforced plastic or multi-material) reduces the weight of structures, but for critical parts that support important forces or temperature, the indicated materials are alloys based on nickel or titanium. Consumption of titanium for the aerospace industry is growing rapidly, and the new generations of aircraft show an increase in the percentage of titanium. The TA6V is mostly used for structural parts, especially for engine pylon. Due to its low thermal properties, it shows a poor machinability, leading tools to undergo severe wears. The aim of this work is to understand the relation between cutting conditions and chamfered tool geometries on chip formation and tool wear. Based on a model dedicated to the understanding of cutting process with chamfered tool and on experimental tests, this work will show the influence of feed, cutting speed, chamfer length and rake angle on tool–chip contact lengths. It will also show the influence of these parameters on the variability of these contacts within a same geometry or cutting condition. This will lead to another interpretation of tool wears and pressures on the rake face.

Damage due to delamination is an important issue during drilling in glass-fiber-reinforced plastic composite laminates. Feed-rate during drilling is the most critical parameter. High feed-rate during drilling results in high thrust force on the composite laminate. In this work, dynamics of drilling in glass-fiber-reinforced plastic composite laminates are captured in the form of third-order state-space model between thrust force and feed-rate. Optimal control is then used to control the thrust force generated during drilling. Research has revealed that there is a critical limit on thrust force during drilling in composite laminate below which no delamination occurs. This critical thrust force profile is used in this work as reference in the optimal controller to ensure delamination-free drilling. Present controller precisely tracks the given critical thrust force reference profile and gives optimal feed-rate profile. The glass-fiber-reinforced plastic composite laminate is then drilled at this optimal feed-rate profile to obtain delamination-free holes. Delamination around the holes is quantified in the form of a delamination factor. Experimental results show that the control strategy is efficient and effective in preventing drilling-induced delamination in glass-fiber-reinforced plastic composite laminates.

Taguchi’s L₉ orthogonal array has been effectively used to study the effect of process parameters such as voltage, feed rate and electrolyte concentration on material removal rate in context of two different types of electrolyte, namely, aqueous NaCl solution and CuSO₄ mixed aqueous NaCl solution. The results indicated that Cu²⁺ ions formed due to electrochemical reactions prevent the oxidation of Fe²⁺ to Fe³⁺ and catalyze the anodic dissolution of iron during machining. The experimental results were analyzed using analysis of variance method to investigate the significance and percentage contribution of individual process parameters on performance characteristics.

Sustainability assessment is becoming an unquestionable issue for manufacturing companies that are urged by governments and customers to provide environment-friendly products. Machining, as one of the major manufacturing operations, has high potential factors regarding the environmental impacts of production system. Nevertheless, environmental assessments are mainly done post-product design and post-machining processes design. Integrating environmental assessment in the machining processes design could lead to significant improvements in sustainable manufacturing field. Major difficulties to perform such an assessment are the availability of the machining data and the lack of calculation rules to express them in terms of environmental impacts. This article presents a new approach based on the STandard for the Exchange of Product model data—compliant Numerical Control to integrate the machining environmental assessment in the earlier design phases. It proposes to establish cognitive links between the machining data included in STandard for the Exchange of Product model data—compliant Numerical Control and environmental indicators. The approach is implemented on a demonstrator and validated by a use case.

Unlike previous studies that have revealed a link between quality improvement programs and organizational culture typologies in individual companies, this study describes organizational culture dimensions that affect the use of quality improvement tools and methodologies and how both affect supply chain company performance. Structural equation modeling methods are applied to a sample of 200 organizations in the supply chain of a Canadian multinational company. The results show that employee promotion and investment constitutes the most influential cultural dimension. Organizational objectives and an employee reward system individually affect Kaizen. When the level of formalization in an organization is high, Kaizen and total quality management tools are used more intensively. When the level of formalization is low, lean manufacturing and internal audits are used more intensively. Superior communication in an organization causes plan–do–check–act approaches, lean manufacturing methods, corrective actions and internal audits to be used less intensively. Generally speaking, most quality improvement tools and methodologies positively influence business performance. These results suggest that organizations can improve business performance levels by selecting appropriate quality improvement programs depending on existing organizational culture dimensions and may thereby develop an organizational culture that enables successful quality improvements in a supply chain context.