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The intention of this paper is to propose a methodology for interactions between the two quality tools of quality function deployment (QFD) and failure mode effects analysis (FMEA), and place an emphasis on their common features. The paper will also emphasise the value that both tools have when used throughout the product development cycle. An example of the method described will be highlighted within Ford Motor Company that will demonstrate the quality and resource benefits achievable when these two tools are used in conjunction with one another. This example will illustrate how, through the use of crossfunctional and multidisciplined teamwork, QFD and FMEA can be linked into systems engineering and a quality operating system with far‐reaching benefits.

There are a number of major prerequisites in the planning, design and operation of all manufacturing systems. These include resource planning, production flow analysis and reliability assessment. The application of these methods form an integral part of an overall feasibility study, the result of which leads to a desired system configuration. Analytical techniques have been employed as corrective tools to amend proposed configurations in an iterative manner. Their role is to reduce the host of initial options that are proposed, thereby arriving at the optimum. There are two main shortcomings with these traditional analytical procedures. Firstly, the complex algorithms formulated are inflexible and dedicated to particular measures of performance. Secondly, they are generally used independently and this gives untold problems for integration within the iterative procedure. These problems are further exacerbated by the diversity of interdependent features associated with flexible batch manufacturing environment, and by external perturbations that can break‐down their steady state characteristics. There is a major need for a robust tool to be established that forms a coherent manufacturing control strategy and will minimise the effect of disturbances on the performance of manufacturing systems. The achievement of this in real‐time by an intelligent‐based package is a tall order. The formation of an expert system off‐line, however, is quite feasible. Such a system using discrete‐change simulation is formulated. The method encompasses production flow control as well as reliability prediction analysis. The established methodology is then applied to a real industrial system to configure the most appropriate operational philosophy over any desired production period.

Compression rings are the main sources of frictional losses in internal combustion engines. The present paper aims to present a thermo-mixed hydrodynamic analysis for coated top compression rings. To understand the coating effects, the main tribological parameters are investigated into a ring-cylinder conjunction in a motorbike engine. Furthermore, flow simulations have been carried out on how different worn profiles on the cylinder inner liner affects friction, lubricant film and localized contact deformation of the coated compression rings.

In this paper, the basic geometrical dimensions of the top compression ring-cylinder system are obtained from a real motorbike engine. A 2D axisymmetric CFD/FLOTRAN model is created for coated compression rings. Flow simulations are performed by solving the Navier-Stokes and the energy equations. The load capacity of the asperities is also taken into account by Greenwood and Tripp contact model. Realistic boundary conditions are imposed to simulate the in-plane ring motion. The simulation model is validated with analytical and experimental data from the literature. Under thermal considerations, the contribution of worn cylinder profiles in conjunction with different coated compression rings is presented.

This research shows that because of thermal effects, the boundary friction is higher at reversals and the viscous friction is lower because of reduced oil viscosity. As regards to the isothermal case, the viscous friction is greater because of a higher lubricant viscosity. In the case of chromium-plated ring, boundary friction was 16 per cent lower than a grey cast iron ring taking into account thermal effects. Regarding the localized contact deformation, the coated compression rings showed lower values under different worn cylinder shapes. In particular, hard wear-resistant (Ni-Cr-Mo) coating showed the slighter local deformation. Therefore, the worn cylinder profiles promote boundary/mixed lubrication regime, whereas the lobed profile of cylinder inner liner becomes more wavy.

The solution of the thermo-mixed lubrication model, concerning the piston ring and worn cylinder tribo pair by taking into account the coating of the top compression ring.

Ever since the bronze age, graphical representations have been employed to convey a message or a phenomenon. Graphical representations have been and continue to be a powerful tool to record events and changes throughout history. It is often helpful to use conceptual models to visualise problems, and in order to find possible solutions. Manufacturing planning and control (MPC) as a discipline is no exception to this rule. Many useful methods/models in this field including Gantt charts, CPM, PERT, and fishbone diagrams have been employed. However, representing complex multi‐variate problems through ordinary conceptual models can be quite arduous and the results may not be objectively accurate. This paper illustrates how a chain of “state‐space” models can be formed, based on the analytic hierarchy process (AHP), which can pertain to existing complex practical manufacturing circumstances in an objective manner.

Analytic hierarchy process (AHP) is a simple decision‐making tool to deal with complex, unstructured and multi‐attribute problems. Selection of the most suitable production planning system (push or pull systems) requires the development of a tool to address quantitative and qualitative parameters which influence success of push‐and‐pull systems’ implementation. This paper presents a multi‐criteria approach within AHP to classify the most appropriate production planning system, based on push, pull or hybrid systems’ methodologies.

Currently, lubrication analysis of piston ring is generally done under engine rated operating condition. However, the engine (such as the vehicle engine) does not always operate in rated operating condition, and its operating condition changes frequently in actual use. In addition, the lubrication status of piston ring is generally assumed as the flooded lubrication or a certain form of poor lubrication in most of the lubrication analysis.

In this paper, based on the equations about the flow rate of lubricating oil and the variation of control volume, the flow model of lubricating oil in the piston ring-cylinder liner conjunction is established. The lubrication analysis of piston ring for a four-stroke engine under different engine operating conditions is done, in which the lubricating oil at the inlet of piston ring is considered as the lubricating oil attached on the relevant location of cylinder wall after the piston ring moves over at the previous stroke.

There is remarkable difference for the lubrication characteristics of the piston ring under different engine operating conditions. The worst lubrication status of piston ring may not take place under engine rated operating condition.

In this paper, based on the measured engine cylinder pressure, the lubrication analysis of piston ring for a four-stroke engine under different engine operating conditions is done in which the lubricating oil supply condition at the inlet of piston ring is considered. The results of this paper are helpful for the design and research of engine piston ring-cylinder liner conjunction.

The purpose of this study is to investigate the combined effect of surface force, solvation and Van der Waals forces and surface topography parameters of amplitude and wavelength on the formation of ultrathin films for elastohydrodynamic lubrication of point contact problems.

The Newton–Raphson technique is used to simultaneously solve the Reynolds’ film thickness including surface roughness and elastic deformation, surface force of solvation and Van der Waals forces and load balance equations. Different values of surface amplitude and wavelength were simulated in addition to the load variation.

The simulation results revealed that roughness effects are important as the film thickness decreases. The oscillation in the pressure and film thickness is due to the combined action of the solvation force and surface topography parameters. The limiting values of the surface topography parameters of the amplitude and wavelength varied and depended on the load. For different values of wavelength and load, amplitude values up to 0.25 nm have no effect on ultrathin film formation.

The combined effect of the surface force and surface roughness on the formation of ultrathin films was evaluated for elastohydrodynamic lubrication of point contact problems under different operating conditions of load and surface topography parameters of amplitude and wavelength. The limited surface topography parameters of the amplitude and wavelength are shown and analyzed.

The purpose of this paper is to investigate the performance of an ultra-thin film lubricated conjunction through the elastohydrodynamic lubrication of point contacts for various ridge shapes and sizes located within the contact zone including flat-top, triangle and cosine wave profiles, considering the influence of surface forces of solvation and Van der Waals’ in addition to the hydrodynamic effect to predict an optimum geometric characteristics for surface texture for lubricated conjunctions.

Surface features are simulated in a variety of sizes and shapes including flat-top, triangle and cosine wave profiles. While estimating the elastic deformation of the contacting surfaces, surface forces of solvation and Van der Waals’ are taken into account. The Reynolds equation is solved using the Newton–Raphson method to get the pressure profile and film thickness including the elastic deformation, and surface feature.

The geometrical characteristics of the ridge, its placement in relation to the contact zone and its height all have a significant impact on the performance of ultra-thin film lubricated conjunction. When the triangular-shaped ridge is present in contact, it forecasts even sharper peaks in film thickness and pressure. More friction, wear and eventually contact fatigue are brought on by this more acute pressure and film thickness peaks. The flat-top ridge shape shows a better performance for lubricated conjunction where, the minimum film thickness value is comparable to that obtained for the case of a smooth contact surface. This behavior is attributed to the effect of intermolecular force of solvation. An increase in the size of the ridge results in a step increase in the film thickness for different ridge shapes, particularly for the flat-topped ridge pattern.

Evaluation of the performance of elastohydrodynamic lubricated ultra-thin film conjunction related to film thickness and pressure profile for various ridge surface features of different amplitudes, shapes and sizes located through the contact zone considering the influence of surface forces of solvation and Van der Waals’ in addition to the hydrodynamic effect.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-03-2023-0062/

The purpose of this study is to investigate the behavior of ultra-thin film formation at the start-up of motion for different acceleration rates and final entrainment speed, including the effect of intermolecular forces; solvation and Van der Waals’ in addition to hydrodynamic action for the elastohydrodynamic lubrication of point contact problems.

The equation of motion of the ball is considered to account for the applied force on the ball during the start-up of motion. The Newton–Raphson with Gauss–Seidel iterative method is used to solve the Reynolds, film thickness and load balance equations simultaneously. In addition to hydrodynamic effects, solvation and Van der Waals’ forces are taken into account in the calculation of bearing capacity.

The simulation results showed that the effects of acceleration rate are important for ultra-thin film formation at the start-up of motion. Increasing the rate of acceleration results in a higher value of central film thickness during the start-up of motion than the corresponding steady-state film thickness value reached at the final entrainment speed. The effects of intermolecular forces are important to prevent metal-to-metal contact during the inactive period of motion, where a constant value of film thickness is achieved regardless of the value of the acceleration rate or final entrainment speed.

The behavior of ultra-thin film formation at start-up of motion, including the effect of intermolecular forces; solvation and Van-der-Waals’ along with hydrodynamic action, are evaluated after different acceleration rates and final entrainment speeds.

Bearing performance characteristics, such as stiffness and load capacity, are related to the viscosity of the fluid circulating through the gap. Nanoparticle additives in lubricant are one way to enhance of the viscosity. This study aims to investigate the effect of nanoparticle additives on the thermohydrodynamic performance of journal bearing with different bearing parameters.

The temperature distribution is modeled using a three-dimensional energy equation. The velocity components are calculated on the pressure distribution governed by Dowson’s equation. Moreover, the heat transfer between the journal and lubricant is modeled with Fourier heat conduction equation. On the other hand, the viscosity equation is derived for Al₂O₃ nanoparticles as a function of the volume ratio and the temperature. An algorithm based on the finite difference method is developed, and a serial simulation is performed for different parameters and different volume ratio of nanoparticle.

With the increase in the nanoparticle volume ratio, the maximum temperature decreases for the lower clearance values, but the addition of the nanoparticle influence on the maximum temperature reverses when the clearance grows up. The nanoparticle additives increase further the maximum temperature for higher values of L/D ratios. Moreover, the effects of the nanoparticle additives on the pressure are stronger at high eccentricity ratios for all bearing parameters.

This paper provides valuable design parameters for journal bearing with lubricant containing the nanoparticle additives.